CN115268090A - Optical correlator, optical correlation computing method and optical computing device - Google Patents

Abstract

The embodiments of the present application disclose an optical correlator, an optical correlation computing method, and an optical computing device, which are mainly used in one-dimensional sequence matching scenarios such as gene sequence alignment, barcode alignment, and text library retrieval. The optical correlator includes a light source, a one-dimensional spatial light modulator SLM, a light beam expanding device, a first refractive device, a two-dimensional SLM, a second refractive device and a light detector. The light source is used to emit light beams. One-dimensional SLM is used to modulate the light beam output by the light source. The light beam expanding device is used for expanding the beam modulated by the one-dimensional SLM in the second direction. The first refraction device is used for condensing the expanded beam in the first direction. A two-dimensional SLM is used to modulate the converged beam. The second refraction device is used for collimating the light beam modulated by the two-dimensional SLM. The photodetector is used for pixel collection of the light beam collimated by the second refraction device, so as to obtain light field information of multiple correlation peaks.

Description

Optical correlator, optical correlation computing method and optical computing device

technical field

The present application relates to the field of optical computing, in particular to an optical correlator, an optical correlation calculation method and an optical computing device.

Background technique

Optical computing uses optical characteristics to realize signal processing in the optical domain, which has the advantages of low power consumption and short computing time. Among them, the optical correlator (optical correlator) is an optical system that uses optical methods to achieve signal correlation processing. It is based on Fourier optics, transforms and processes light fields in free space, and can realize data (signal, coding, images, etc.) matching and searching.

The current optical correlators are all based on Fourier transform in two-dimensional space, and their main function is to match two-dimensional images, which is difficult to apply to one-dimensional sequence matching. Specifically, the optical correlator uses a two-dimensional spatial light modulator (Spatial Light Modulator, SLM) and a two-dimensional light detector. If the input is multiple lines of different one-dimensional sequences, each line of one-dimensional sequence needs to be matched multiple times, and finally there will be more matching results on the two-dimensional photodetector, which is difficult to distinguish. However, if a one-dimensional sequence is input one row at a time in a time-division manner, the overall calculation time will be longer and the matching process will be slower.

Contents of the invention

Embodiments of the present application provide an optical correlator, an optical correlation calculation method, and an optical calculation device. The optical correlator is applied to a one-dimensional sequence matching scene, and a single operation can complete the matching of the target sequence and multiple sets of reference sequences, which reduces the time-consuming operation and improves the sequence matching speed.

In a first aspect, the present application provides an optical correlator. The optical correlator includes: a light source, a one-dimensional SLM, an optical beam expander, a first refraction device, a two-dimensional SLM, a second refraction device and a light detector. The back focal plane of the first refraction device coincides with the front focal plane of the second refraction device, the exit pupil plane of the beam expander is located at the front focal plane of the first refraction device, and the two-dimensional SLM is located at the back focal plane of the first refraction device, The light detector is located at the back focal plane of the second refraction device. Specifically, a light source is used to emit light beams. One-dimensional SLM is used to modulate the beam output by the light source. Wherein, the one-dimensional SLM is loaded with a group of electrical signals corresponding to the target sequence, and the one-dimensional SLM includes a row of pixels arranged in a first direction. The optical beam expander is used for expanding the beam modulated by the one-dimensional SLM in the second direction. Wherein, the second direction is perpendicular to the first direction, and the second direction is perpendicular to the direction in which the light beam enters the optical beam expander. The first refraction device is used for converging the expanded beam in the first direction. A two-dimensional SLM is used to modulate the converged beam. Wherein, the two-dimensional SLM is loaded with multiple sets of electrical signals corresponding to the reference sequences, and the two-dimensional SLM includes multiple rows of pixel points arranged in the first direction. The second refraction device is used for collimating the light beam modulated by the two-dimensional SLM. The light detector is used for pixel collection of the light beam collimated by the second refraction device.

In this embodiment, the beam modulated by the one-dimensional SLM is spatially expanded, so that a row of target sequences loaded on the one-dimensional SLM can be copied into the same multiple rows of target sequences. Afterwards, the multiple rows of the same target sequence can be correlated with multiple rows of reference sequences loaded on the 2D SLM at the same time to achieve one-to-one matching. It is equivalent to completing the matching of the target sequence and multiple sets of reference sequences in one operation, reducing the time consumption of correlation operations and improving the efficiency of sequence matching.

In some possible implementation manners, the one-dimensional SLM transmits the modulated beam to the beam expander, and the two-dimensional SLM transmits the modulated beam to the second refraction device. That is, the one-dimensional SLM and the two-dimensional SLM provided in this application are both transmission-type SLMs, which enhances the feasibility of this solution.

In some possible implementations, the optical correlator further includes a first beam splitter and a second beam splitter. The first beam splitter is used to split the expanded beam. Wherein, the split first beam is transmitted to the first refracting device, and the split second beam is transmitted to the second beam splitter. The second beam splitter is used to transmit the second beam to the first refraction device. Through the above method, on the basis of expanding the beam by the optical beam expander, a new beam can also be added through the first beam splitter and the second beam splitter, which is equivalent to further expanding the beam and improving the target sequence. The number of copies is further doubled, which improves the computing efficiency.

In some possible implementations, one of the beams split by the first beam splitter is transmitted along the first direction or the second direction, that is to say, the application can transmit in multiple different directions through the first beam splitter The expanded beam increases the flexibility of the scheme.

In some possible implementation manners, the optical correlator further includes a first polarization beam splitter and a second polarization beam splitter. The first polarizing beam splitter is used for splitting the expanded beam. Wherein, the first polarization beam splitter transmits the beam of the first polarization direction to the first refraction device, the first polarization beam splitter transmits the beam of the second polarization direction to the second polarization beam splitter, and the first polarization direction and the second polarization beam splitter The two polarization directions are orthogonal to each other. The second polarization beam splitter is used to transmit the light beam in the second polarization direction to the first refraction device. Through the above method, since the second polarization beam splitter receives only the light beam of the second polarization direction, it only needs to reflect the light beam of the second polarization direction to the first refraction device, and no light beam will pass through the second polarization beam splitter. The device reduces unnecessary waste of light beams. Moreover, on the basis of expanding the beam by the optical beam expander, a new beam can be added through the first polarizing beam splitter and the second polarizing beam splitter, which is equivalent to further doubling the number of copies of the target sequence , improving the operational efficiency.

In some possible implementation manners, the optical correlator further includes a light reflecting device and a third beam splitter. The one-dimensional SLM is specifically used to reflect the modulated beam to the optical beam expander. The reflective device is used to reflect the expanded beam to the first refracting device. The third beam splitter is used to transmit the converged light beam to the two-dimensional SLM. The two-dimensional SLM is used to modulate the received beam, and reflect the modulated beam to the third beam splitter. The third beam splitter is also used to transmit the light beam modulated by the two-dimensional SLM to the second refraction device. Through the above method, both the one-dimensional SLM and the two-dimensional SLM are reflective SLMs, and a reflective device and a third beam splitter are added to change the optical path, thereby realizing a folded optical path. It avoids that all devices are arranged in the same direction, and the folded optical path is more convenient for integration in a limited space, and it is also easier to realize miniaturization.

In some possible implementation manners, the light source includes a laser and a beam collimating device. Lasers are used to emit beams of light. The beam collimating device is used to collimate the beam emitted by the laser, and output the collimated beam to the one-dimensional SLM. In this implementation manner, a specific implementation manner of a light source is provided, which enhances the feasibility of this solution.

In some possible implementation manners, the optical beam expander includes a first lens and a second lens. The first lens is used for converging the light beam modulated by the one-dimensional SLM in the second direction. The second lens is used to collimate the light beam converged by the first lens. In this implementation manner, a specific implementation manner of an optical beam expander is provided, which further enhances the feasibility of this solution.

In some possible implementation manners, the optical beam expander is further configured to shrink the beam modulated by the one-dimensional SLM in the first direction, so as to better match the size of the two-dimensional SLM.

In some possible implementation manners, the light detector includes a plurality of pixels, and each pixel is used to collect light field information of a correlation peak. Since the present application only matches the one-dimensional sequence, the photodetector can specifically adopt a one-dimensional detector, that is, the photodetector only includes one column of pixel points, and the cost is lower than that of a two-dimensional detector.

In some possible implementations, the optical correlator further includes a controller. The controller is used to: send a group of electrical signals corresponding to the target sequence to the one-dimensional SLM, so as to drive the one-dimensional SLM to modulate the light beam output by the light source. Send multiple sets of electrical signals corresponding to the reference sequence to the two-dimensional SLM to drive the two-dimensional SLM to modulate the received light beam. The output signal sent by the light detector is received, and the matching result between the target sequence and multiple groups of reference sequences is determined according to the output signal, and the output signal includes the light field information of multiple correlation peaks. In this embodiment, the input and output of electrical signals can be realized through the controller, so as to realize automatic control.

In some possible implementation manners, the controller is further configured to: send an electrical signal corresponding to the updated set of target sequences to the one-dimensional SLM, so as to control the one-dimensional SLM to update the loaded target sequences. Sending electrical signals corresponding to the updated multiple sets of reference sequences to the two-dimensional SLM, so as to control the two-dimensional SLM to update the loaded multiple sets of reference sequences. Wherein, the update frequency of the one-dimensional SLM is greater than or equal to the update frequency of the two-dimensional SLM. In this implementation manner, the controller can also control the one-dimensional SLM and the two-dimensional SLM to update the respective loaded sequences, and this way of automatically controlling the update improves the working efficiency of the optical correlator.

In some possible implementation manners, the controller is further configured to send control signals to the one-dimensional SLM, the two-dimensional SLM and the photodetector, so as to control the one-dimensional SLM, the two-dimensional SLM and the photodetector to maintain clock synchronization. Therefore, it is ensured that the photodetector can update the sampling information after each update of the one-dimensional SLM and the two-dimensional SLM.

In some possible implementations, the first refraction device is a cylindrical lens or a Fourier lens, and the second refraction device is a cylindrical lens or a Fourier lens, which enhances the scalability of the solution.

In some possible implementations, the photodetector may be a Charge Coupled Device (Charge Coupled Device, CCD) camera or a Complementary Metal Oxide Semiconductor (Complementary Metal Oxide Semiconductor, CMOS). Specifically, the two-dimensional SLM may be liquid crystal on silicon (Liquid Crystal on Silicon, Lcos).

In a second aspect, the present application provides an optical correlation calculation method. The method includes the following steps. Sends a beam of light through a light source. The beam output by the light source is modulated by a one-dimensional SLM. The one-dimensional SLM is loaded with a group of electrical signals corresponding to the target sequence, and the one-dimensional SLM includes a row of pixels arranged in a first direction. The light beam modulated by the one-dimensional SLM is expanded in the second direction by the optical beam expander. The second direction is perpendicular to the first direction, and the second direction is perpendicular to the direction in which the light beam enters the optical beam expander. The expanded beam is converged in the first direction by the first refracting device. The converged beam is modulated by a 2D SLM. The two-dimensional SLM is loaded with electrical signals corresponding to multiple sets of reference sequences, and the two-dimensional SLM includes multiple rows of pixels arranged in a first direction. The light beam modulated by the two-dimensional SLM is collimated by the second refraction device. The light beam collimated by the second refraction device is collected by a photodetector. Wherein, the back focal plane of the first refraction device coincides with the front focal plane of the second refraction device, the exit pupil plane of the beam expander is located at the front focal plane of the first refraction device, and the two-dimensional SLM is located at the back focal plane of the first refraction device The photodetector is located on the back focal plane of the second refraction device.

In some possible implementation manners, after the light beam output by the light source is modulated by the one-dimensional SLM, the modulated light beam is transmitted to the optical beam expander. After the converged light beam is modulated by the two-dimensional SLM, the modulated light beam is transmitted to the second refraction device.

In some possible implementation manners, the method further includes: splitting the expanded beam through a first beam splitter. Wherein, the split first beam is transmitted to the first refracting device, and the split second beam is transmitted to the second beam splitter. The second light beam is transmitted to the first refraction device through the second beam splitter.

In some possible implementation manners, one of the branched light beams is transmitted along the first direction or the second direction.

In some possible implementation manners, the method further includes: splitting the expanded beam by using a first polarization beam splitter. Wherein, the first polarization beam splitter transmits the beam of the first polarization direction to the first refraction device, the first polarization beam splitter transmits the beam of the second polarization direction to the second polarization beam splitter, and the first polarization direction and the second polarization beam splitter The two polarization directions are orthogonal to each other. The light beam in the second polarization direction is transmitted to the first refraction device through the second polarization beam splitter.

In some possible implementation manners, the method further includes: reflecting the modulated light beam to an optical beam expander through a one-dimensional SLM. The reflective device is used to reflect the expanded beam to the first refracting device. The converged light beam is transmitted to the two-dimensional SLM through the third beam splitter. The two-dimensional SLM is used to modulate the received light beam, and reflect the modulated light beam to the third beam splitter. The light beam modulated by the two-dimensional SLM is transmitted to the second refraction device through the third beam splitter.

In some possible implementation manners, emitting a light beam through a light source includes: emitting a light beam through a laser. The beam emitted by the laser is collimated by the beam collimating device, and the collimated beam is output to the one-dimensional SLM.

In some possible implementation manners, expanding the beam modulated by the one-dimensional SLM in the second direction through the optical beam expander includes: expanding the beam modulated by the one-dimensional SLM in the second direction through the first lens to converge. The beam converged by the first lens is collimated by the second lens.

In some possible implementation manners, the method further includes: shrinking the light beam modulated by the one-dimensional SLM in the first direction by an optical beam expander.

In some possible implementation manners, the light detector includes a plurality of pixels, and each pixel is used to collect light field information of a correlation peak.

In some possible implementation manners, the method further includes: sending a group of electrical signals corresponding to the target sequence to the one-dimensional SLM, so as to drive the one-dimensional SLM to modulate the light beam output by the light source. Send multiple sets of electrical signals corresponding to the reference sequence to the two-dimensional SLM to drive the two-dimensional SLM to modulate the received light beam. The output signal sent by the light detector is received, and the matching result between the target sequence and multiple groups of reference sequences is determined according to the output signal, and the output signal includes the light field information of multiple correlation peaks.

In some possible implementation manners, the method further includes: sending an electrical signal corresponding to the updated set of target sequences to the one-dimensional SLM, so as to control the one-dimensional SLM to update the loaded target sequences. Sending electrical signals corresponding to the updated multiple sets of reference sequences to the two-dimensional SLM to control the two-dimensional SLM to update the loaded multiple sets of reference sequences, wherein the update frequency of the one-dimensional SLM is greater than or equal to the update frequency of the two-dimensional SLM.

In some possible implementation manners, the method further includes: sending a control signal to the one-dimensional SLM, the two-dimensional SLM and the photodetector, so as to control the one-dimensional SLM, the two-dimensional SLM and the photodetector to maintain clock synchronization.

In some possible implementation manners, the first refraction device is a cylindrical lens or a Fourier lens, and the second refraction device is a cylindrical lens or a Fourier lens.

In some possible implementation manners, the light detector is a CCD camera or a CMOS camera, and the two-dimensional SLM is Lcos.

In a third aspect, the present application provides an optical correlator. The optical correlator includes: a light source, a one-dimensional SLM, a light beam expander, a light reflection device, a first beam splitter, a refraction device, a two-dimensional SLM and a light detector. The exit pupil plane of the light beam expander is located on the front focal plane of the refraction device, and the two-dimensional SLM is located on the back focal plane of the refraction device. A light source is used to emit light beams. The one-dimensional SLM is used to modulate the beam output by the light source, and reflect the modulated beam to the beam expander. The one-dimensional SLM is loaded with a group of electrical signals corresponding to the target sequence, and the one-dimensional SLM includes a row of pixels arranged in a first direction. The optical beam expander is used for expanding the beam modulated by the one-dimensional SLM in the second direction. The second direction is perpendicular to the first direction, and the second direction is perpendicular to the direction in which the light beam enters the optical beam expander. The light reflecting device is used to reflect the expanded beam to the first beam splitter. The first beam splitter is used to transmit the light beam reflected by the light reflecting device to the refracting device. The refraction device is used for converging the beam reflected by the beam splitter in the first direction. The two-dimensional SLM is used to modulate the converged beam and reflect the modulated beam to the refraction device. The two-dimensional SLM is loaded with electrical signals corresponding to multiple sets of reference sequences, and the two-dimensional SLM includes multiple rows of pixels arranged in a first direction. The refraction device is also used to collimate the beam reflected by the 2D SLM. The first beam splitter is also used to transmit the beam collimated by the refraction device to the photodetector. The photodetector is used for pixel acquisition of the input light beam.

In some possible implementation manners, the optical correlator further includes a second beam splitter and a third beam splitter. The second beam splitter is used to split the expanded beam. Wherein, the split first light beam is transmitted to the reflective device. The split second beam is sent to the third beam splitter. The third beam splitter is used to transmit the second light beam to the reflective device.

In some possible implementation manners, one of the beams split by the second beam splitter is transmitted along the first direction or the second direction.

In some possible implementation manners, the optical correlator further includes a first polarization beam splitter and a second polarization beam splitter. The first polarizing beam splitter is used for splitting the expanded beam. Wherein, the first polarization beam splitter transmits the light beam in the first polarization direction to the light reflecting device. The first polarization beam splitter transmits the light beam in the second polarization direction to the second polarization beam splitter. The first polarization direction and the second polarization direction are orthogonal to each other. The second polarization beam splitter is used to transmit the light beam in the second polarization direction to the reflective device.

In some possible implementations, the light source includes a laser and a beam collimating device. Lasers are used to emit beams of light. The beam collimating device is used to collimate the beam emitted by the laser, and output the collimated beam to the one-dimensional SLM.

In some possible implementation manners, the optical beam expander includes a first lens and a second lens. The first lens is used for converging the light beam modulated by the one-dimensional SLM in the second direction. The second lens is used to collimate the light beam converged by the first lens.

In some possible implementation manners, the optical beam expander is further configured to shrink the beam modulated by the one-dimensional SLM in the first direction.

In some possible implementation manners, the light detector includes a plurality of pixels, and each pixel is used to collect light field information of a correlation peak.

In some possible implementation manners, the optical correlator further includes a controller, and the controller is configured to: send a group of electrical signals corresponding to the target sequence to the one-dimensional SLM, so as to drive the one-dimensional SLM to modulate the light beam output by the light source. Send multiple sets of electrical signals corresponding to the reference sequence to the two-dimensional SLM to drive the two-dimensional SLM to modulate the received light beam. The output signal sent by the light detector is received, and the matching result between the target sequence and multiple groups of reference sequences is determined according to the output signal, and the output signal includes the light field information of multiple correlation peaks.

In some possible implementation manners, the controller is further configured to: send an electrical signal corresponding to the updated set of target sequences to the one-dimensional SLM, so as to control the one-dimensional SLM to update the loaded target sequences. Sending electrical signals corresponding to the updated multiple sets of reference sequences to the two-dimensional SLM, so as to control the two-dimensional SLM to update the loaded multiple sets of reference sequences. Wherein, the update frequency of the one-dimensional SLM is greater than or equal to the update frequency of the two-dimensional SLM.

In some possible implementation manners, the controller is further configured to: send a control signal to the one-dimensional SLM, the two-dimensional SLM and the photodetector, so as to control the one-dimensional SLM, the two-dimensional SLM and the photodetector to maintain clock synchronization.

In some possible implementation manners, the refraction device is a cylindrical lens or a Fourier lens.

In some possible implementations, the light detector is a CCD camera or a CMOS camera. 2D SLM is Lcos.

In a fourth aspect, the present application provides an optical correlation calculation method. The method includes the following steps. Used by light sources to emit light beams. The beam output by the light source is modulated by the one-dimensional SLM, and the modulated beam is reflected to the beam expander. The one-dimensional SLM is loaded with a group of electrical signals corresponding to the target sequence, and the one-dimensional SLM includes a row of pixels arranged in a first direction. The light beam modulated by the one-dimensional SLM is expanded in the second direction by the optical beam expander. The second direction is perpendicular to the first direction, and the second direction is perpendicular to the direction in which the light beam enters the optical beam expander. The expanded beam is reflected to the first beam splitter through the reflector. The first beam splitter is used to transmit the light beam reflected by the reflection device to the refraction device. The light beam reflected by the beam splitter is converged in the first direction by the refraction device. The converged light beam is modulated by a two-dimensional SLM, and the modulated light beam is reflected to the refraction device. The two-dimensional SLM is loaded with electrical signals corresponding to multiple sets of reference sequences, and the two-dimensional SLM includes multiple rows of pixels arranged in a first direction. The beam reflected by the two-dimensional SLM is also collimated by a refraction device. The light beam collimated by the refraction device is also transmitted to the photodetector through the first beam splitter. The input light beam is pixel-collected by a photodetector. The exit pupil plane of the light beam expander is located on the front focal plane of the refraction device, and the two-dimensional SLM is located on the back focal plane of the refraction device.

In some possible implementation manners, the optical correlator further includes a second beam splitter and a third beam splitter. The method also includes: splitting the expanded beam through a second beam splitter. Wherein, the split first light beam is transmitted to the reflective device. The split second beam is sent to the third beam splitter. The second light beam is transmitted to the reflective device through the third beam splitter.

In some possible implementation manners, one of the beams split by the second beam splitter is transmitted along the first direction or the second direction.

In some possible implementation manners, the optical correlator further includes a first polarization beam splitter and a second polarization beam splitter. The method further includes: splitting the expanded beam through a first polarization beam splitter. Wherein, the first polarization beam splitter transmits the light beam in the first polarization direction to the light reflecting device. The first polarization beam splitter transmits the light beam in the second polarization direction to the second polarization beam splitter. The first polarization direction and the second polarization direction are orthogonal to each other. The light beam in the second polarization direction is transmitted to the reflective device through the second polarization beam splitter.

In some possible implementations, the light source includes a laser and a beam collimating device. Using the light source for emitting the light beam includes: emitting the light beam through the laser. The beam emitted by the laser is collimated by the beam collimating device, and the collimated beam is output to the one-dimensional SLM.

In some possible implementation manners, the optical beam expander includes a first lens and a second lens. Expanding the beam modulated by the one-dimensional SLM in the second direction by the optical beam expander includes: converging the beam modulated by the one-dimensional SLM in the second direction through the first lens. The beam converged by the first lens is collimated by the second lens.

In some possible implementation manners, the method further includes: shrinking the light beam modulated by the one-dimensional SLM in the first direction by an optical beam expander.

In some possible implementation manners, the light detector includes a plurality of pixels, and each pixel is used to collect light field information of a correlation peak.

In some possible implementation manners, the method further includes: sending a group of electrical signals corresponding to the target sequence to the one-dimensional SLM, so as to drive the one-dimensional SLM to modulate the light beam output by the light source. Send multiple sets of electrical signals corresponding to the reference sequence to the two-dimensional SLM to drive the two-dimensional SLM to modulate the received light beam. The output signal sent by the light detector is received, and the matching result between the target sequence and multiple groups of reference sequences is determined according to the output signal, and the output signal includes the light field information of multiple correlation peaks.

In some possible implementation manners, the method further includes: sending an electrical signal corresponding to the updated set of target sequences to the one-dimensional SLM, so as to control the one-dimensional SLM to update the loaded target sequences. Sending electrical signals corresponding to the updated multiple sets of reference sequences to the two-dimensional SLM, so as to control the two-dimensional SLM to update the loaded multiple sets of reference sequences. Wherein, the update frequency of the one-dimensional SLM is greater than or equal to the update frequency of the two-dimensional SLM.

In some possible implementation manners, the method further includes: sending a control signal to the one-dimensional SLM, the two-dimensional SLM and the photodetector, so as to control the one-dimensional SLM, the two-dimensional SLM and the photodetector to maintain clock synchronization.

In some possible implementation manners, the refraction device is a cylindrical lens or a Fourier lens.

In some possible implementations, the light detector is a CCD camera or a CMOS camera. 2D SLM is Lcos.

In the fifth aspect, the present application provides an optical computing device, the optical computing device includes a processor and the optical correlator in any implementation manner of the first aspect and the third aspect above, and the processor is used to output a set of Target sequence and multiple sets of reference sequences.

In the embodiment of the present application, the beam modulated by the one-dimensional SLM is spatially expanded, so that a row of target sequences loaded on the one-dimensional SLM can be copied into the same multiple rows of target sequences. Afterwards, the multiple rows of the same target sequence can be correlated with multiple rows of reference sequences loaded on the 2D SLM at the same time to achieve one-to-one matching. It is equivalent to completing the matching of the target sequence and multiple sets of reference sequences in one operation, reducing the time consumption of correlation operations and improving the efficiency of sequence matching.

Description of drawings

Fig. 1 is a kind of structural representation of the optical correlator applied to two-dimensional image matching;

Fig. 2 is a kind of structural representation of optical correlator in the present application;

Fig. 3 (a) is a kind of three-dimensional structure schematic diagram of optical correlator in the present application;

Fig. 3 (b) is a kind of plane front view of optical correlator in the present application;

Fig. 3 (c) is a kind of plane top view of optical correlator in the present application;

Fig. 4 is a schematic diagram of correlation peaks on the photodetector in the present application;

Fig. 5 (a) is another kind of plane front view of optical correlator in the present application;

Fig. 5 (b) is another kind of top plan view of optical correlator in the present application;

Fig. 6 (a) is another kind of plane front view of optical correlator in the present application;

Fig. 6 (b) is another kind of top plan view of optical correlator in the present application;

Fig. 7 is another kind of top plan view of the optical correlator in the present application;

Fig. 8 (a) is another kind of plane front view of optical correlator in the present application;

Fig. 8 (b) is another kind of plane front view of the optical correlator in the present application;

Fig. 8 (c) is another kind of plane front view of the optical correlator in the present application;

Fig. 9 (a) is another kind of plane front view of the optical correlator in the present application;

Fig. 9 (b) is another kind of plane front view of the optical correlator in the present application;

Fig. 9 (c) is another kind of top view of the optical correlator in the present application;

Figure 9(d) is another plan view of the optical correlator in the present application;

FIG. 10 is a schematic diagram of an embodiment of an optical correlation calculation method provided by the present application.

Detailed ways

Embodiments of the present application provide an optical correlator, an optical correlation calculation method, and an optical calculation device. The optical correlator is applied to a one-dimensional sequence matching scene, and a single operation can complete the matching of the target sequence and multiple sets of reference sequences, which reduces the time-consuming operation and improves the sequence matching speed. The terms "first", "second" and the like in the description and claims of the present application and the above drawings (if any) are used to distinguish similar objects and not necessarily to describe a specific order or sequence. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or device comprising a sequence of steps or elements is not necessarily limited to the expressly listed instead, may include other steps or elements not explicitly listed or inherent to the process, method, product or apparatus.

Fig. 1 is a schematic structural diagram of an optical correlator applied to two-dimensional image matching. Most of the current optical correlators are based on Fourier transform in two-dimensional space, and their main function is to match two-dimensional images. As shown in FIG. 1 , the light output by the light source S is collimated into parallel light after passing through the collimating lens L1. The focal lengths of Fourier transform lenses L2 and L3 are both f, and the rear focal plane of Fourier transform lens L2 coincides with the front focal plane of Fourier transform L3, forming a 4f optical path structure. Correspondingly, the front focal plane of the Fourier transform lens L2 is the object plane, on which a two-dimensional spatial light modulator (Spatial LightModulator, SLM) P1 is placed. The back focal plane of the Fourier transform lens L2 is a spectrum plane, on which the two-dimensional spatial light modulator P2 is placed. The back focal plane of the Fourier transform lens L3 is the image plane, on which the two-dimensional detector array P3 is placed. The Fourier transform lenses L2 and L3 respectively implement an Optical Fourier Transform (OFT).

The two-dimensional spatial light modulators P1 and P2 perform corresponding two-dimensional light field modulation on the input parallel light beams according to the electrical signal carrying the two-dimensional modulation amount matrix information. Wherein, light field modulation includes light intensity modulation and phase modulation. The modulation amount matrix information corresponding to the two-dimensional spatial light modulator P1 is a two-dimensional matrix A1. The modulation amount matrix information corresponding to the two-dimensional spatial light modulator P2 is the Fourier transform of the two-dimensional matrix A2. Through two OFT operations of L2 and L3, the output beam is received by the two-dimensional detector array P3 and converted into an electrical signal carrying the information of the two-dimensional correlation matrix C12, and then demodulated to obtain the two-dimensional correlation matrix C12. Through the above process, the optical correlator converts the two electrical signals corresponding to the two-dimensional matrix A1 and the two-dimensional matrix A2 into optical signals. In the optical domain, the correlation operation of the two-dimensional matrix A1 and the two-dimensional matrix A2 is realized, and the optical signal corresponding to the information of the two-dimensional matrix C12 is obtained, which is converted into an electrical signal and finally the two-dimensional matrix C12 is extracted.

However, the above-mentioned optical correlator is difficult to be applied in one-dimensional sequence matching scenarios, such as gene sequence alignment, barcode alignment, text library retrieval, etc. One of the typical application scenarios is gene sequence alignment. In this scenario, a standard sequence preprocessing of the human genome is prepared as a reference sequence database. Specifically include: determining the length of the gene sequence, dividing the length of the gene sequence, constructing a reference sequence according to the code corresponding to the base of the gene sequence, and extracting the spectrum or phase spectrum of the one-dimensional Fourier transform of the reference sequence. Afterwards, the gene sequence to be matched is coded according to its base correspondence to form the target sequence. Furthermore, the encoded target sequence and the reference sequence database are sent to the optical correlator, and then the comparison and positioning of the target sequence in the reference sequence database can be performed.

First, the above-mentioned optical correlator uses a two-dimensional SLM and a two-dimensional detector array. Limited by physical devices and production processes, two-dimensional SLMs and two-dimensional detector arrays have slow conversion speeds for electrical signals and optical signals, resulting in slow input and output speeds. Therefore, the above-mentioned optical correlator is more suitable for two-dimensional image matching with a low refresh rate, and it is difficult to apply to one-dimensional sequence matching with a high refresh rate. Second, assume that the input of the two-dimensional SLM is multiple lines of different one-dimensional sequences, for example, 100 lines of target sequences to be matched. If there are 100 rows of reference sequences stored in the database, 10,000 matching results will eventually be obtained. The number of correlation peaks presented on the two-dimensional detector array is large, and it is difficult to distinguish them when superimposed. However, if a one-dimensional sequence is input one row at a time in a time-division manner, the overall calculation time will be longer and the matching process will be slower.

For this reason, the present application provides an optical correlator applied to one-dimensional sequence matching, which can complete the matching of the target sequence and multiple sets of reference sequences in one operation, which reduces the time-consuming operation and improves the sequence matching speed. Details are given below.

FIG. 2 is a schematic structural diagram of an optical correlator in the present application. As shown in FIG. 2 , the optical correlator includes a light source 10 , a one-dimensional SLM 20 , a beam expander 30 , a first refraction device 40 , a two-dimensional SLM 50 , a second refraction device 60 and a photodetector 70 . Wherein, the solid line in FIG. 2 is used to represent the transmission of light beams, and the dotted line is used to represent the transmission of electrical signals. A group of target sequences is loaded to the one-dimensional SLM 20 in the form of electrical signals, and multiple sets of reference sequences are loaded to the two-dimensional SLM 50 in the form of electrical signals. The light detector 70 collects the light field information of the correlation peaks after performing correlation calculations between a group of target sequences and multiple groups of reference sequences. Specifically, laser light emitted from the light source 10 is transmitted to the one-dimensional SLM 20 . The one-dimensional SLM 20 performs beam modulation to modulate a set of target sequences onto the beam. The optical beam expander 30 expands the modulated beam, and the divergence angle of the beam after beam expansion becomes smaller and the beam waist diameter becomes larger, which is equivalent to spatially copying a group of target sequences into multiple groups of identical target sequences. The first refraction device 40 refracts the expanded beam to realize optical Fourier transform, wherein the Fourier transform spectra of multiple sets of target sequences are the same. The two-dimensional SLM 50 modulates the input beam, and the output beam modulates the point-by-point product of multiple sets of Fourier transform spectra of target sequences and multiple sets of Fourier transform spectra of reference sequences. The second refraction device 60 refracts the input beam to realize the inverse optical Fourier transform, and the output beam modulates the result of the correlation operation, and the correlation operation can be obtained by performing the inverse Fourier transform after the above-mentioned point-by-point product The result of this correlation operation is a function distribution. The light detector 70 samples the input light beam to obtain the light field information of multiple correlation peaks, which is used to reflect the result of the above correlation calculation. Specifically, the light field distribution of the correlation peak corresponds to the function distribution of the correlation operation result, wherein the maximum value of the light field intensity of the correlation peak corresponds to the maximum value of the function distribution of the correlation operation result. The light field information of multiple correlation peaks can reflect the correlation calculation results between a set of target sequences and multiple sets of reference sequences. It should be noted that the modulation of the light beam by the above-mentioned one-dimensional SLM 20 includes light intensity modulation and/or phase modulation. Similarly, the modulation of the light beam by the above-mentioned two-dimensional SLM 50 also includes light intensity modulation and/or phase modulation. There is no limit here.

It should be noted that the above-mentioned optical correlator further includes a controller 80 as shown in FIG. 2 . The controller 80 is used to provide input electrical signals to the one-dimensional SLM 20 and the two-dimensional SLM 50 , and is also used to receive electrical signals output from the photodetector 70 . Specifically, the controller 80 sends an electrical signal including a target sequence to the one-dimensional SLM 20, and sends an electrical signal including multiple sets of reference sequences to the two-dimensional SLM 50, so as to respectively drive the one-dimensional SLM 20 and the two-dimensional SLM 50 to input The beam is modulated. The light field information of the correlation peak collected by the photodetector 70 can also be output to the controller 80 through an electrical signal, and the controller 80 determines the matching result between the target sequence and multiple sets of reference sequences according to the light field information of the correlation peak. In addition, when the target sequence needs to be updated, the controller 80 will also send the updated target sequence to the one-dimensional SLM 20, so that the one-dimensional SLM 20 can update the loaded target sequence. Similarly, when the reference sequence needs to be updated, the controller 80 will also send the updated reference sequence to the 2D SLM 50, so that the 2D SLM 50 can update the loaded reference sequence. Wherein, the updating frequency of the one-dimensional SLM 20 should be higher than that of the two-dimensional SLM 50 . It should be understood that the detection rate of the photodetector 70 should be greater than or equal to the modulation rate of the one-dimensional SLM 20, so as to ensure that the photodetector 70 can update the sampling information after each update of the one-dimensional SLM 20, for example, the modulation rate of the one-dimensional SLM is 500KHz, and the detection rate of the light detector 70 is ≥500KHz. In some possible implementations, the controller 80 may also send control signals to the one-dimensional SLM 20, the two-dimensional SLM 50 and the photodetector 70, so as to control the clock synchronization between the photodetector 70 and the one-dimensional SLM 20 and the two-dimensional SLM 50 . That is to say, after the one-dimensional SLM 20 is updated many times, the two-dimensional SLM 50 can be updated once, and each update of the one-dimensional SLM 20 and the two-dimensional SLM 50 also needs to let the photodetector 70 update its collection synchronously. Information. In practical applications, the controller 80 may be a device integrated inside the optical correlator, or an independent device outside the optical correlator, which is not specifically limited here. It should be understood that each embodiment described below also includes the above-mentioned controller. For the convenience of introduction, the function of the controller will not be introduced in each embodiment below, and the controllers will not be shown one by one in the subsequent drawings. up.

The optical correlator provided by the present application will be further introduced through multiple specific embodiments below. For ease of introduction, firstly, the first direction and the second direction in the following figures are defined. Wherein, the pixels on the one-dimensional SLM 20 are arranged in the first direction, and there is only one row of pixels distributed on the one-dimensional SLM 20 . The pixels on the two-dimensional SLM 50 are also arranged in the first direction, but there are multiple rows of pixels distributed on the two-dimensional SLM 50 . The optical beam expander 30 expands the beam in a second direction, the second direction is perpendicular to the first direction, and the second direction is also perpendicular to the direction in which the beam enters the optical expander 30 .

Embodiment one:

Fig. 3(a) is a schematic diagram of a three-dimensional structure of the optical correlator in the present application. Fig. 3(b) is a planar front view of the optical correlator in this application. Fig. 3(c) is a top plan view of the optical correlator in the present application. As shown in FIG. 3( a )- FIG. 3( c ), the exit pupil plane of the beam expander 30 is located on the front focal plane of the first refracting device 40 . The two-dimensional SLM 50 is located on the back focal plane of the first refraction device 40, and the back focal plane of the first refraction device 40 coincides with the front focal plane of the second refraction device. The light detector 70 is located at the back focal plane of the second refraction device 60 .

The light source 10 includes a laser 101 and a beam collimating device 102 , and the application does not limit the specific types of the laser 101 and the beam collimating device 102 . As an example, the laser 101 may be a linear divergent laser, and the beam collimating device 102 is a cylindrical lens. As shown in FIG. 3( b ), the beam collimating device 102 is used to collimate the beam output by the laser 101 . As another example, the beam collimating device 102 can also adopt a collimating and homogenizing lens. The collimating and homogenizing lens can change the single-mode Gaussian laser emitted by the laser 101 into Gaussian light with a divergence angle of about ±5°, and in the Gaussian beam The energy distribution is homogenized during the divergence process, and the collimating homogenization lens not only has a collimating effect on the light beam but also has a converging effect, so that the light beam output by the light source 10 can be converged to a row of pixels on the one-dimensional SLM 20 .

A row of pixels arranged along the first direction on the one-dimensional SLM 20 corresponds to a group of target sequences loaded on the one-dimensional SLM 20 . The target sequence may be a bit sequence, and the value of each bit in the sequence is 0 or 1. The target sequence may also be a sequence with higher gray levels, such as a sequence with 8-level gray levels, and the value range of each bit in the sequence is 0-255 (2 ⁸ ), which is not limited here. The number of pixels on the one-dimensional SLM 20 should be greater than or equal to the number of coding units of the target sequence, and each coding unit can adopt binary or multi-value coding. That is to say, on the one-dimensional SLM 20 , each coding unit of the target sequence can be assigned a corresponding pixel. As an example, the target sequence is a gene sequence with 100 fragments, the target sequence contains 1000 coding units in total, and the coding value of each coding unit is 0 or 1, and the one-dimensional SLM 20 includes 1000 pixels on a line, 1000 There is a one-to-one correspondence between pixels and 1000 coding units. Every 10 coding units corresponds to a fragment, and each fragment is one of the four base types of AGCT. There are four different arrangements corresponding to the four bases, for example, 1010101010 corresponds to A, 1001001001 corresponds to G, 1001110001 corresponds to C, and 0110101010 corresponds to T.

The beam expander 30 includes a first lens 301 and a second lens 302 . The first lens 301 and the second lens 302 constitute a telescope-like system to expand the input beam. Specifically, the input beam is expanded in the second direction, so that a set of target sequences modulated on the input beam can be spatially copied into multiple sets of target sequences, which can be used to combine with multiple sets of target sequences loaded on the two-dimensional SLM 50. group reference sequences for matching. The application does not limit the types of the first lens 301 and the second lens 302 . As an example, both the first lens 301 and the second lens 302 are cylindrical lenses. As shown in FIG. 3( b ), the first lens 301 and the second lens 302 only change the direction of the light beam in the second direction. Preferably, the size of the beam expanded by the beam expander 30 should match the size of the two-dimensional SLM 50 , so as to just cover multiple rows of pixel points on the two-dimensional SLM 50 . For example, there are 2000 rows of pixels distributed on the two-dimensional SLM 50. If the expanded beam can only cover 1000 rows of pixels, only 1000 matching results can be obtained in the end, and the two-dimensional SLM 50 cannot be used to the maximum extent. If the size of the post-beam beam is too large, only 2000 matching results can be obtained at most, which will also cause unnecessary waste.

It should be noted that the above introduction to the optical beam expander 30 is just an example, and in practical applications, an optical beam expander with other structures can also be used to expand the input beam, which is not specifically limited here. For example, the optical beam expander 30 may also be a coupling lens, and the coupling lens may specifically include four cylindrical lenses. It should be understood that the above-mentioned first lens 301 and second lens 302 can only expand the beam in the second direction, on this basis, the coupling lens can be configured with two lenses similar to the first lens 301 and the second lens 302, The difference is that these two lenses only redirect the light beam in a first direction. Therefore, the input light beam can also be narrowed in the first direction through the coupling lens, so as to better match the size of the two-dimensional SLM 50 .

As shown in Figure 3(b), the first refraction device 40 is used to converge the expanded beam in the first direction to perform a one-dimensional optical Fourier transform to transform the light intensity distribution in the spatial domain distribution in the frequency domain. The present application does not limit the type of the first refraction device 40 , as an example, the first refraction device 40 is a cylindrical lens. As another example, the first refraction device 40 may also be a Fourier lens. In order to ensure the spatial domain sampling rate of the Fourier transform, the Fourier lens may use a telephoto lens to realize the transformation function. Specifically, the Fourier lens can be composed of multiple cylindrical lenses, and the aperture of the Fourier lens should cover the effective optical area of the two-dimensional SLM 50 .

The two-dimensional SLM 50 includes multiple rows of pixel points, wherein each set of reference sequences loaded on the two-dimensional SLM 50 has a corresponding row of pixel points. Specifically, the correspondence manner between each group of reference sequences and a row of pixel points may refer to the above-mentioned correspondence manner between pixels on the one-dimensional SLM 20 and the target sequence, and will not be repeated here. It should be understood that the one-dimensional SLM 20 and the two-dimensional SLM 50 in this embodiment are all transmissive SLMs, and the light beams modulated by the one-dimensional SLM 20 and the two-dimensional SLM 50 will be transmitted to subsequent devices. In some possible implementation manners, the two-dimensional SLM 50 may specifically be a liquid crystal on silicon (Liquid Crystal on Silicon, Lcos).

As shown in FIG. 3( b ), the second refraction device 60 is used to collimate the input light beam to perform a one-dimensional inverse optical Fourier transform to convert the frequency domain distribution into the spatial domain light intensity distribution. The present application also does not limit the type of the second refraction device 60 , and for the specific type, reference may be made to the above introduction to the first refraction device 40 , which will not be repeated here.

As shown in FIG. 3( a ), since the present application only performs matching on one-dimensional sequences, the light detector 70 may specifically be a one-dimensional detector. The photodetector 70 includes a column of pixels, which are used to collect the input light beams by pixels, so as to obtain the light field information of multiple correlation peaks. In this embodiment, the pixel points on the photodetector 70 can be understood as pixel points arranged along the second direction. For example, if there are 2000 rows of pixels on the two-dimensional SLM 50 , there should be 2000 pixels in this column on the photodetector 70 . As an example, the photodetector 70 is used to receive the intensity of the light beam, and extract the correlation peak intensity according to each pixel point, and then, the controller 80 can compare the intensity of each correlation peak with a threshold to determine the matching result.

Fig. 4 is a schematic diagram of the correlation peaks on the photodetector in the present application. As shown in Figure 4, only the peak value of the correlation peak in the third row exceeds the threshold value, and the peak values in the other rows all exceed the peak value. Therefore, the target sequence loaded on the one-dimensional SLM 20 and the third row reference sequence loaded on the two-dimensional SLM50 match and did not match any other reference sequences. In some possible implementations, the photodetector 70 may be a Charge Coupled Device (Charge Coupled Device, CCD) camera or a Complementary Metal Oxide Semiconductor (Complementary Metal Oxide Semiconductor, CMOS).

Embodiment two:

Fig. 5(a) is another planar front view of the optical correlator in this application. Fig. 5(b) is another top plan view of the optical correlator in this application. As shown in Figure 5(a) and Figure 5(b), the difference between the second embodiment and the above-mentioned first embodiment is that the output of the light source 10 in the first embodiment is a collimated beam, while the output of the light source 10 in the second embodiment is diverging beams. Specifically, the light source 10 only includes a laser 101 . The divergent beam output by the laser 101 will continue to diverge after reaching the one-dimensional SLM 20 , and the divergent beam reaching the optical beam expander 30 is also a divergent beam. Therefore, different from the above-mentioned first embodiment, the optical beam expander 30 in the second embodiment only includes a lens 302, and the lens 302 is used to collimate the input diverging light beam and output it. It should be understood that, except for the differences described above, other devices of the optical correlator in Embodiment 2 are similar to those described in Embodiment 1, for example, the one-dimensional SLM 20, the first refraction device 40, the two-dimensional For the SLM 50 , the second refraction device 60 and the photodetector 70 , reference may be made to the relevant description of Embodiment 1, and details will not be repeated here. It can be known from the above description that the structure of the second embodiment is simpler than that of the first embodiment, and the use of the optical correlator with the structure of the second embodiment can save costs in some scenarios.

Embodiment three:

Fig. 6(a) is another planar front view of the optical correlator in this application. Fig. 6(b) is another top plan view of the optical correlator in this application. As shown in Figure 6(a), the difference between the third embodiment and the first embodiment is that, in the third embodiment, a first beam splitter 90 and a second beam splitter 90 are added between the optical beam expander 30 and the first refraction device 401. Beamer 100. Specifically, the first beam splitter 90 is used to split the input light beam, wherein the split first beam is transmitted to the first refraction device 401, and the split second beam is transmitted to the second split beam. Beamer 100. As an example, the first beam splitter 90 may transmit one beam and reflect the other beam. The first refraction device 401 may be on the transmitted light beam and the second beam splitter 100 on the reflected light path, or the first refraction device 401 may be on the reflected light beam and the second beam splitter 100 on the transmitted light path. Taking FIG. 6( a ) as an example, the first beam is transmitted to the first refraction device 401 through the first beam splitter 90 , and the second beam is reflected to the second beam splitter 100 through the first beam splitter 90 . The second beam splitter 100 further splits the input beam, and the function of the second beam splitter 100 is similar to that of the first beam splitter 90 . Still taking FIG. 6( a ) as an example, one beam is reflected to the first refraction device 402 through the second beam splitter 100 , and the other beam is transmitted through the second beam splitter 100 . Based on the above method, on the basis of expanding the beam by the optical beam expander 30, a new beam can also be added through the first beam splitter 90 and the second beam splitter 100, which is equivalent to expanding the beam in the second direction. With further beam expansion, the number of copies of the target sequence is further doubled, which improves the computational efficiency. It should be understood that since the light beam is split into two paths in the second direction, then the devices behind the first beam splitter 90 and the second beam splitter 100 also need to be increased by one group accordingly, for example, as shown in FIG. 6( a ). The first refraction device 402, the two-dimensional SLM 502, the second refraction device 602 and the photodetector 702 are shown. In addition, the first refraction device 40 with a larger size can also be used so that it can receive two beams, so that there is no need to configure two first refraction devices. Similarly, the two-dimensional SLM 50 , the second refraction device 60 and the photodetector 70 may also use larger devices, which will not be repeated here. It should be noted that the above-mentioned first beam splitter 90 and the second beam splitter 100 perform light splitting based on the energy of the light beam, and the present application does not limit the light splitting ratio.

The difference between Fig. 6(b) and Fig. 6(a) is that the first beam splitter 90 and the second beam splitter 100 shown in Fig. 6(b) split the input light beam in the first direction, The number of copies of the target sequence can also be further doubled, improving the computational efficiency. The working principles of the first beam splitter 90 and the second beam splitter 100 are similar to those described in the embodiment shown in FIG. 6( a ), and will not be repeated here. It should be understood that in practical applications, the beam can be divided in the manner shown in FIG. 6(a), or the beam can be divided in the manner shown in FIG. The methods shown in a) and FIG. 6(b) split the light beams, which are not specifically limited here. It should be noted that, except that the newly added first beam splitter 90 is reflected to the second beam splitter 100 , other devices in this embodiment are similar to those described in Embodiment 1, and will not be repeated here. The light source 10 and the optical beam expander 30 in the third embodiment may also adopt the structure introduced in the second embodiment, which is not limited here.

Embodiment four:

Fig. 7 is another top plan view of the optical correlator in the present application. As shown in Figure 7, the difference between Embodiment 4 and Embodiment 1 is that in Embodiment 4, a first polarization beam splitter 110 and a second polarization beam splitter 110 are added between the optical beam expander 30 and the first refraction device 401 device 120. The difference between the fourth embodiment and the third embodiment is that the first polarizing beam splitter 110 and the second polarizing beam splitter 120 perform splitting based on the polarization direction of the input beam. Specifically, the first polarization beam splitter 110 is used to split the input beam, where the beam in the first polarization direction is transmitted to the first refraction device 401 after the split, and the beam in the second polarization direction is transmitted to the The second beam splitter 100. As an example, the first polarization beam splitter 110 can transmit one beam and reflect the other beam. The first refraction device 401 may be on the transmitted beam, and the second polarizing beam splitter 120 is on the reflected light path, or the first refracting device 401 may be on the reflected beam, and the second polarizing beam splitter 120 is on the transmitted light on the way. Taking FIG. 7 as an example, the light beam in the first polarization direction is transmitted to the first refraction device 401 , and the light beam in the second polarization direction is reflected to the second polarization beam splitter 120 . Wherein, the first polarization direction and the second polarization direction are orthogonal to each other. Since the second polarization beam splitter 120 receives only the light beam of the second polarization direction, it only needs to reflect the light beam of the second polarization direction to the first refraction device 402, and no light beam will pass through the second polarization beam splitter 120 , compared with the third embodiment, the unnecessary waste of light beams is reduced. Based on the above method, on the basis of expanding the beam by the optical beam expander 30, a new beam can also be added through the first polarizing beam splitter 110 and the second polarizing beam splitter 120, which is equivalent to copying the target sequence The number is further doubled, which improves the computing efficiency. It should be understood that the above-mentioned first polarization direction and the second polarization direction may be mutually orthogonal in the plane of the plan view as shown in FIG. 7, or may be mutually orthogonal in the plane of the front view as shown in FIG. 6(a), Specifically, there is no limitation here. It should also be understood that since the light beam is divided into two paths, the devices after the first polarizing beam splitter 110 and the second polarizing beam splitter 120 need to be added correspondingly, such as the first refraction beam shown in FIG. device 402 , two-dimensional SLM 502 , second refraction device 602 and light detector 702 . In addition, the first refraction device 40 with a larger size may also be used so that it can receive two beams, so that there is no need to configure two first refraction devices. Similarly, the two-dimensional SLM 50 , the second refraction device 60 and the photodetector 70 may also use larger devices, which will not be repeated here. It should be noted that, except for the newly added first polarizing beam splitter 110 and the second polarizing beam splitter 120 , other devices in this embodiment are similar to those described in Embodiment 1, and will not be repeated here. The light source 10 and the optical beam expander 30 in the fourth embodiment may also adopt the structure introduced in the second embodiment, which is not limited here.

Embodiment five:

Fig. 8(a) is another planar front view of the optical correlator in this application. Fig. 8(b) is another planar front view of the optical correlator in this application. Fig. 8(c) is another planar front view of the optical correlator in this application. As shown in Figure 8(a), the difference between the fifth embodiment and the first embodiment is that the one-dimensional SLM 20 and the two-dimensional SLM 50 in the fifth embodiment are reflective SLMs, and a new reflective device 130 and The beam splitter 140 is used to change the optical path, thereby realizing a folded optical path. The implementation of the fifth embodiment avoids that all devices are arranged in the same direction, and the folded optical path facilitates integration in a limited space and facilitates miniaturization. Specifically, the one-dimensional SLM 20 reflects the modulated beam to the optical beam expander 30 . The reflective device 130 reflects the beam output by the beam expander 30 to the first refracting device 40 . The beam splitter 140 splits the beam output by the first refraction device 40 , wherein one beam reflected by the beam splitter 140 is transmitted to the two-dimensional SLM 50 . Afterwards, the beam splitter 140 splits the light beams reflected by the two-dimensional SLM 50 , wherein one beam transmitted by the beam splitter 140 is transmitted to the second refraction device 60 . A beam of light reflected by the beam splitter 140 will also be transmitted back to the first refraction device 40, and the components on the return light path can be designed to be insensitive to the return light. It should be understood that, except for the differences described above, other components of the optical correlator in Embodiment 5 are similar to those described in Embodiment 1, and will not be repeated here.

The difference between Fig. 8(b) and Fig. 8(a) is that in the embodiment shown in Fig. 8(b), the one-dimensional SLM 20 is a reflective SLM, the two-dimensional SLM 50 is a transmissive SLM, and other The functions of the components are similar to those of the embodiment shown in FIG. 8( a ), and will not be repeated here. The difference between Fig. 8(c) and Fig. 8(a) is that in the embodiment shown in Fig. 8(c), the one-dimensional SLM 20 is a transmissive SLM, the two-dimensional SLM 50 is a reflective SLM, and a new reflective device is added. 150. The light reflecting device 150 is used to reflect the light beam output by the optical beam expander 30 to the light reflecting device 130, and the functions of other components are similar to the embodiment shown in Fig. 8(a), and will not be repeated here. . It should be understood that on the basis of the above-mentioned embodiments shown in Figure 8(a)-Figure 8(c), the light path can also be flexibly changed through devices such as reflectors and beam splitters, and other similar implementations based on this design idea All methods are within the protection scope of the present application. It should also be understood that Embodiment 5 may also be used in combination with the differences of at least one implementation manner in Embodiment 2 to Embodiment 4, which is not specifically limited here.

Embodiment six:

The difference between the sixth embodiment and the above-mentioned several embodiments is that in the sixth embodiment, only one refraction device can be used to realize the functions of the above-mentioned first refraction device and the second refraction device. That is to say, in the sixth embodiment, only the refraction device 40 needs to be provided, and the refraction device 40 successively realizes an optical Fourier transform and an optical inverse Fourier transform. In some application scenarios, the components of the optical correlator can be reduced, saving cost and use of space. It should be understood that in the sixth embodiment, the two-dimensional SLM 50 needs to adopt a reflective SLM, which will be described below through several specific examples. Fig. 9(a) is another planar front view of the optical correlator in this application. Fig. 9(b) is another planar front view of the optical correlator in this application. Fig. 9(c) is another top plan view of the optical correlator in this application. Fig. 9(d) is another top plan view of the optical correlator in the present application.

As shown in Fig. 9(a), this embodiment adopts a folded optical path similar to that shown in Fig. 8(a) above. Specifically, both the one-dimensional SLM 20 and the two-dimensional SLM 50 are reflective SLMs. The one-dimensional SLM 20 reflects the modulated beam to the beam expander 30 . The reflective device 130 reflects the beam output by the beam expander 30 to the beam splitter 140 . The beam splitter 140 splits the input beams, wherein one beam reflected by the beam splitter 140 is transmitted to the refraction device 40 . The refraction device 40 first converges the input beam, then collimates the beam reflected by the two-dimensional SLM 50 , and outputs the beam to the beam splitter 140 . The beam splitter 140 then splits the beam from the refraction device 40 , wherein one beam transmitted by the beam splitter 140 is transmitted to the photodetector 70 .

As shown in Fig. 9(b), this embodiment adopts a folded optical path similar to that shown in Fig. 8(c) above. Specifically, the one-dimensional SLM 20 is a transmissive SLM, and the two-dimensional SLM 50 is a reflective SLM. The one-dimensional SLM 20 transmits the modulated beam to the beam expander 30 . The reflective device 150 reflects the light beam output by the beam expander 30 to the reflective device 130 . The light reflecting device 130 reflects the beam to the beam splitter 140 again. The beam splitter 140 splits the input beams, wherein one beam reflected by the beam splitter 140 is transmitted to the refraction device 40 . The refraction device 40 first converges the input beam, then collimates the beam reflected by the two-dimensional SLM 50 , and outputs the beam to the beam splitter 140 . The beam splitter 140 then splits the beam from the refraction device 40 , wherein one beam transmitted by the beam splitter 140 is transmitted to the photodetector 70 .

It should be understood that other components of the optical correlator shown in FIG. 9( a ) and FIG. 9( b ) are similar to those described in Embodiment 1 except for the differences described above, and will not be repeated here. It should also be understood that the optical correlators shown in FIG. 9(a) and FIG. 9(b) can also be used in combination with the differences of at least one implementation in Embodiment 2 to Embodiment 4, which will not be specifically described here. limited. The above-mentioned Fig. 9 (a) and Fig. 9 (b) can be understood as the transformation carried out on the basis of the fifth embodiment, and the following Fig. 9 (c) can be understood as the transformation carried out on the basis of the third embodiment, Fig. 9(d) can be understood as a transformation based on the fourth embodiment.

As shown in Fig. 9(c), this embodiment adopts an optical path similar to that shown in Fig. 6(b) above. Specifically, the one-dimensional SLM 20 is a transmissive SLM, and the two-dimensional SLM 50 is a reflective SLM. The first beam splitter 90 splits the beam from the optical beam expander 30, wherein one beam is transmitted to the refraction device 401 through the first beam splitter 90, and the other beam is reflected to the second splitter through the first beam splitter 90. Beamer 100. The second beam splitter 100 further splits the input beams, wherein one beam is reflected to the refraction device 402 through the second beam splitter 100 , and the other beam is transmitted through the second beam splitter 100 . The refraction device 401 first converges the input beam, then collimates the beam reflected by the two-dimensional SLM 501 , and outputs the beam to the first beam splitter 90 . Similarly, the refraction device 402 first converges the input beam, then collimates the beam reflected by the two-dimensional SLM 502 , and outputs the beam to the second beam splitter 100 . The first beam splitter 90 then splits the beam from the refraction device 401 , wherein one beam reflected by the beam splitter 140 is transmitted to the photodetector 701 . The second beam splitter 100 then splits the beam from the refraction device 402 , wherein one beam transmitted by the beam splitter 100 is transmitted to the photodetector 702 .

As shown in FIG. 9( d ), this embodiment employs an optical path similar to that shown in FIG. 7 above. Specifically, the one-dimensional SLM 20 is a transmissive SLM, and the two-dimensional SLM 50 is a reflective SLM. The first polarization beam splitter 110 splits the light beam from the optical beam expander 30, wherein the light beam in the first polarization direction is transmitted to the refraction device 401 through the first beam splitter 110, and the light beam in the second polarization direction passes through the first splitting The beam splitter 110 reflects to the second polarizing beam splitter 120 . The second polarization beam splitter 120 further reflects the light beam in the second polarization direction to the refraction device 402 . The refraction device 401 first converges the input beam, then collimates the beam reflected by the two-dimensional SLM 501 , and outputs the beam in the first polarization direction to the first polarization beam splitter 110 . Similarly, the refraction device 402 first converges the input beam, then collimates the beam reflected by the two-dimensional SLM 502 , and outputs the beam with the second polarization direction to the second polarization beam splitter 120 . The first polarization beam splitter 110 then reflects the light beam in the first polarization direction to the light detector 701 . The second beam splitter 100 then transmits the light beam in the second polarization direction to the light detector 702 . It should be understood that other components of the optical correlator shown in FIG. 9( c ) and FIG. 9( d ) are similar to those described in Embodiment 1 except for the differences described above, and will not be repeated here. It should also be understood that the light source 10 and the beam expander 30 in FIG. 9(c) and FIG. 9(d) may also adopt the structure introduced in Embodiment 2, which is not specifically limited here.

The embodiment of the present application also provides an optical computing device, and the optical correlator introduced in any of the above embodiments can be integrated in the optical computing device. Moreover, the optical computing device further includes a processor. Specifically, the processor is used to output a set of target sequences and multiple sets of reference sequences to the controller in the optical correlator. Furthermore, the controller sends a set of electrical signals corresponding to the target sequence to the one-dimensional SLM, and sends multiple sets of electrical signals corresponding to the reference sequence to the two-dimensional SLM. In addition, the controller can also output the matching results of a set of target sequences and multiple sets of reference sequences to the processor. The processor further combines the actual application scenarios to perform corresponding processing according to the matching results, for example, further judging the corresponding diseases according to the matching results of the gene sequence. It should be noted that the optical computing device may be a server, or a single board, etc., which is not specifically limited here.

In the embodiment of the present application, the beam modulated by the one-dimensional SLM is spatially expanded, so that a row of target sequences loaded on the one-dimensional SLM can be copied into the same multiple rows of target sequences. Afterwards, the multiple rows of the same target sequence can be correlated with multiple rows of reference sequences loaded on the 2D SLM at the same time to achieve one-to-one matching. It is equivalent to completing the matching of the target sequence and multiple sets of reference sequences in one operation, reducing the time consumption of correlation operations and improving the efficiency of sequence matching.

The optical correlator in the embodiment of the present application has been introduced above, and an optical correlation operation method realized by using the above optical correlator will be introduced below. FIG. 10 is a schematic diagram of an embodiment of an optical correlation calculation method provided by the present application. In this embodiment, the optical correlation calculation method includes the following steps.

1001. Emit a light beam through a light source.

The light source used in this embodiment may be as shown in any one of the first and second embodiments above, and will not be repeated here.

1002. Use a one-dimensional SLM to modulate the light beam output by the light source.

In this embodiment, for the implementation of specific functions of the one-dimensional SLM, reference may be made to the relevant description of the first embodiment above, and details are not repeated here.

1003. Expand the beam modulated by the one-dimensional SLM in the second direction by using the beam expander.

The optical beam expander used in this embodiment may be shown as the optical beam expander in any one of the first and second embodiments above, and will not be repeated here.

1004. Converge the expanded beam in the first direction by using the first refracting device.

In this embodiment, for the implementation of specific functions of the first refraction device, reference may be made to the relevant description of the first embodiment above, and details are not repeated here.

1005. Use a two-dimensional SLM to modulate the beam converged by the first refraction device.

In this embodiment, for the implementation of specific functions of the two-dimensional SLM, reference may be made to the relevant description of the above-mentioned Embodiment 1, and details are not repeated here.

1006. Collimate the light beam modulated by the two-dimensional SLM by using the second refraction device.

In this embodiment, the implementation of the specific functions of the second refraction device can refer to the relevant description of the first embodiment above, and will not be repeated here.

1007. Use a photodetector to collect pixels of the light beam collimated by the second refraction device, so as to obtain light field information of multiple correlation peaks.

In this embodiment, the implementation of the specific functions of the photodetector can refer to the related description of the above-mentioned embodiment 1, which will not be repeated here.

In some possible implementation manners, the controller may also provide input electrical signals for the one-dimensional SLM and the two-dimensional SLM, and receive the electrical signals output by the photodetector through the controller. For details, please refer to the relevant description about the controller in the above-mentioned embodiment shown in FIG. 2 , which will not be repeated here.

In some possible implementations, on the basis of expanding the beam by the optical beam expander, a new beam can also be added through the processing of the first beam splitter and the second beam splitter, which is equivalent to duplicating the target sequence The number of is further doubled, which improves the computing efficiency. For details, please refer to the relevant description of the third embodiment above, and details are not repeated here.

In some possible implementations, on the basis of expanding the beam by the optical beam expander, a new beam can also be added through the processing of the first polarizing beam splitter and the second polarizing beam splitter, which is equivalent to the target The number of sequence replications is also further doubled, improving operational efficiency. For details, please refer to the relevant description of the fourth embodiment above, which will not be repeated here.

In some possible implementations, the optical path of the light beam in the optical correlator is changed by means of reflective devices, beam splitters and other devices, thereby realizing a folded optical path and avoiding that all devices are arranged in the same direction , it is easier to integrate in a limited space through the folded optical path, and it is also easier to realize miniaturization. For details, please refer to the relevant description of the fifth embodiment above, which will not be repeated here.

It should be noted that the above-mentioned embodiment shown in FIG. 10 is mainly based on the realization method of the optical correlator structure in the above-mentioned first to fifth embodiments. In some possible implementation manners, the optical correlator introduced in Embodiment 6 above may also be used to implement a corresponding optical correlation calculation method. For details, please refer to the relevant description of the sixth embodiment above, which will not be repeated here.

The above is only the specific implementation of the application, but the scope of protection of the application is not limited thereto. Anyone familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the application, and should cover Within the protection scope of this application.

Claims (21)

1. An optical correlator, characterized in that it comprises: a light source, a one-dimensional spatial light modulator SLM, an optical beam expander, a first refraction device, a two-dimensional SLM, a second refraction device and a light detector, the first The rear focal plane of the refraction device coincides with the front focal plane of the second refraction device, the exit pupil plane of the beam expander is located at the front focal plane of the first refraction device, and the two-dimensional SLM is located at the first focal plane of the first refraction device. a back focal plane of a refraction device, the photodetector is located at the back focal plane of the second refraction device; The light source is used to emit light beams; The one-dimensional SLM is used to modulate the light beam output by the light source, the one-dimensional SLM is loaded with a group of electrical signals corresponding to the target sequence, and the one-dimensional SLM includes a row of pixels arranged in a first direction ; The optical beam expander is used to expand the beam modulated by the one-dimensional SLM in a second direction, the second direction is perpendicular to the first direction, and the second direction is parallel to the beam input The direction of the optical beam expander is vertical; The first refraction device is used to converge the expanded beam in the first direction; The two-dimensional SLM is used to modulate the converged light beam, the two-dimensional SLM is loaded with electrical signals corresponding to multiple sets of reference sequences, and the two-dimensional SLM includes multiple sets of signals arranged in the first direction Row pixels; The second refraction device is used to collimate the light beam modulated by the two-dimensional SLM; The light detector is used to collect pixels of the light beam collimated by the second refraction device. 2. The optical correlator according to claim 1, wherein the one-dimensional SLM transmits the modulated beam to the optical beam expander, and the two-dimensional SLM transmits the modulated beam to the Second refraction device. 3. The optical correlator according to claim 1 or 2, wherein the optical correlator further comprises a first beam splitter and a second beam splitter; The first beam splitter is used to split the expanded beam, wherein the split first beam is transmitted to the first refraction device, and the split second beam is transmitted to the the second beam splitter; The second beam splitter is used to transmit the second light beam to the first refraction device. 4. The optical correlator according to claim 3, wherein one of the beams split by the first beam splitter is transmitted along the first direction or the second direction. 5. The optical correlator according to claim 1 or 2, wherein the optical correlator further comprises a first polarization beam splitter and a second polarization beam splitter; The first polarization beam splitter is used to split the expanded beam, wherein the first polarization beam splitter transmits the beam in the first polarization direction to the first refraction device, and the first polarization beam splitter A polarization beam splitter transmits the light beam of the second polarization direction to the second polarization beam splitter, and the first polarization direction and the second polarization direction are orthogonal to each other; The second polarization beam splitter is used to transmit the light beam in the second polarization direction to the first refraction device. 6. The optical correlator according to claim 1, characterized in that, the optical correlator further comprises a light reflecting device and a third beam splitter; The one-dimensional SLM is specifically used to reflect the modulated beam to the optical beam expander; The reflective device is used to reflect the expanded beam to the first refracting device; The third beam splitter is used to transmit the converged light beam to the two-dimensional SLM; The two-dimensional SLM is used to modulate the received beam, and reflect the modulated beam to the third beam splitter; The third beam splitter is also used to transmit the light beam modulated by the two-dimensional SLM to the second refraction device. 7. The optical correlator according to any one of claims 1 to 6, wherein the optical beam expander is also used for adjusting the beam modulated by the one-dimensional SLM in the first direction Perform shrinkage. 8. The optical correlator according to any one of claims 1 to 7, wherein the optical correlator further comprises a controller, the controller is used for: Sending electrical signals corresponding to the set of target sequences to the one-dimensional SLM to drive the one-dimensional SLM to modulate the light beam output by the light source; Sending electrical signals corresponding to the plurality of sets of reference sequences to the two-dimensional SLM to drive the two-dimensional SLM to modulate the received light beam; receiving an output signal sent by the photodetector, and determining a matching result between the target sequence and the multiple sets of reference sequences according to the output signal. 9. The optical correlator according to claim 8, wherein the controller is also used for: Sending an electrical signal corresponding to an updated set of target sequences to the one-dimensional SLM, so as to control the one-dimensional SLM to update the loaded target sequence; Sending electrical signals corresponding to the updated multiple sets of reference sequences to the two-dimensional SLM, so as to control the two-dimensional SLM to update the loaded multiple sets of reference sequences, wherein the update frequency of the one-dimensional SLM is greater than or equal to the The update frequency of the 2D SLM described above. 10. The optical correlator according to claim 8 or 9, wherein the controller is further used for: Sending a control signal to the one-dimensional SLM, the two-dimensional SLM and the photodetector to control the one-dimensional SLM, the two-dimensional SLM and the photodetector to maintain clock synchronization. 11. An optical correlation calculation method, comprising: emit a beam of light through a light source; The light beam output by the light source is modulated by a one-dimensional spatial light modulator SLM, the one-dimensional SLM is loaded with a group of electrical signals corresponding to the target sequence, and the one-dimensional SLM includes a row of pixels arranged in a first direction point; The light beam modulated by the one-dimensional SLM is expanded in a second direction by an optical beam expander, the second direction is perpendicular to the first direction, and the second direction is the same as the light beam input to the light beam The direction of the beam expander is vertical; converging the expanded beam in the first direction by a first refracting device; The converged light beam is modulated by a two-dimensional SLM, the two-dimensional SLM is loaded with electrical signals corresponding to multiple sets of reference sequences, and the two-dimensional SLM includes multiple rows of pixels arranged in the first direction ; Collimating the light beam modulated by the two-dimensional SLM through the second refraction device; The light beam collimated by the second refraction device is collected by a photodetector, wherein the rear focal plane of the first refraction device coincides with the front focal plane of the second refraction device, and the light The exit pupil plane of the beam expander is located at the front focal plane of the first refraction device, the two-dimensional SLM is located at the back focal plane of the first refraction device, and the photodetector is located at the rear of the second refraction device focal surface. 12. The method according to claim 11, wherein after the light beam output by the light source is modulated by the one-dimensional SLM, the modulated light beam is transmitted to the optical beam expander; After the condensed light beam is modulated by the two-dimensional SLM, the modulated light beam is transmitted to the second refraction device. 13. The method according to claim 11 or 12, characterized in that the method further comprises: The expanded beam is split by a first beam splitter, wherein the split first beam is transmitted to the first refraction device, and the split second beam is transmitted to the first Two beam splitters; The second light beam is transmitted to the first refraction device through a second beam splitter. 14. The method according to claim 13, wherein one of the beams split by the first beam splitter is transmitted along the first direction or the second direction. 15. The method according to claim 11 or 12, characterized in that the method further comprises: The expanded beam is split by a first polarization beam splitter, wherein the first polarization beam splitter transmits the beam in the first polarization direction to the first refraction device, and the first polarization The beam splitter transmits the beam of the second polarization direction to the second polarization beam splitter, and the first polarization direction and the second polarization direction are orthogonal to each other; The light beam in the second polarization direction is transmitted to the first refraction device through a second polarization beam splitter. 16. The method of claim 11, further comprising: reflecting the modulated beam to the optical beam expander through the one-dimensional SLM; Reflecting the expanded light beam to the first refracting device through a light reflecting device; transmitting the converged light beam to the two-dimensional SLM through a third beam splitter; The two-dimensional SLM is used to modulate the received beam, and reflect the modulated beam to the third beam splitter; The light beam modulated by the two-dimensional SLM is transmitted to the second refraction device through the third beam splitter. 17. The method according to any one of claims 11 to 16, further comprising: The light beam modulated by the one-dimensional SLM is reduced in the first direction by the optical beam expander. 18. The method according to any one of claims 11 to 17, further comprising: Sending electrical signals corresponding to the set of target sequences to the one-dimensional SLM to drive the one-dimensional SLM to modulate the light beam output by the light source; Sending electrical signals corresponding to the plurality of sets of reference sequences to the two-dimensional SLM to drive the two-dimensional SLM to modulate the received light beam; receiving an output signal sent by the photodetector, and determining a matching result between the target sequence and the multiple sets of reference sequences according to the output signal. 19. The method of claim 18, further comprising: Sending an electrical signal corresponding to the updated set of target sequences to the one-dimensional SLM, so as to control the one-dimensional SLM to update the loaded target sequence; Sending electrical signals corresponding to the updated sets of reference sequences to the two-dimensional SLM to control the two-dimensional SLM to update the loaded sets of reference sequences, wherein the update frequency of the one-dimensional SLM is greater than or is equal to the update frequency of the two-dimensional SLM. 20. The method according to claim 18 or 19, further comprising: Sending a control signal to the one-dimensional SLM, the two-dimensional SLM and the photodetector to control the one-dimensional SLM, the two-dimensional SLM and the photodetector to maintain clock synchronization. 21. An optical computing device, comprising a processor and the optical correlator according to any one of claims 1 to 10, the processor is used to output a set of target sequences and Multiple sets of reference sequences.

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