CN103761979A - Method for detecting signals of multi-dimensional optical storage optical disk - Google Patents

Abstract

A signal detection method for a multi-dimensional optical storage disc. The disc of the multi-dimensional optical storage disc is processed with record characters of different depths and angles. The incident light is focused on the surface of the recording pit through a beam splitter and a focusing lens; Enter the light intensity detector; when the laser is focused on the center of the record, rotate the light source 180°, and read the information of the light intensity in the light intensity detector changing with the angle of the light source; through the rotating light source corresponding to the maximum value of the light intensity signal The angle of the record is distinguished by the angle, and the depth of the record is distinguished by the average amplitude of the light intensity signal. The signal detection method of the multi-dimensional optical storage disc provided by the invention can effectively avoid signal interference between adjacent record characters, significantly improve the signal detection rate of the multi-dimensional optical storage, thereby increasing the density of the multi-dimensional optical storage.

Description

A signal detection method for a multi-dimensional optical storage disc

technical field

The invention belongs to the technical field of photoelectric information storage, and in particular relates to a signal detection method of a novel multi-dimensional optical storage disc.

Background technique

In the 21st century, mankind has entered the information society, and the knowledge economy has become a powerful driving force for promoting social progress and scientific and technological development. Information storage, transmission and processing are one of the most important guarantees for improving the overall development level of society. Due to the multimediaization of information, people now need to deal with moving images and high-definition images. IDC predicts that the total amount of global data will increase by 50 times by 2020, and the demand for data storage will increase by more than 50 times. Facing the 21st century, people urgently need to consider how to effectively store and manage more and more data and how to apply these data. The increasingly crowded information storage space, the increasing complexity of information data collection and data management systems, and the popularity of the Internet will lead to the rise of information technology in the 21st century in the storage field.

Optical information storage (referred to as optical storage) has become an indispensable information carrier in the modern information society. Optical storage technology has the advantages of no modification of historical data, one-time storage number, long life, mass storage, green storage, high cost performance, and exchangeable media. Today's Blu-ray disc capacity can reach 50GB-100GB, which can only meet the current audio/video file transmission needs. In the fields of military defense, finance, press and publication, etc., there is an urgent need for ultra-large capacity discs for file backup and storage. If there is no revolutionary new Technological breakthrough, CD capacity increase space is limited.

Today, the fourth generation of high-density optical storage has the following development directions, holographic, near-field, super-resolution and multi-dimensional optical storage. Among them, the capacity of near-field and super-resolution optical storage technology can only reach 200-300GB, which is still difficult to meet the long-term development needs; only holographic and multi-dimensional optical storage technology can reach more than 1TB capacity, but holographic optical storage technology has compatibility, system Problems such as cost and material stability are difficult to solve in a short time, so multi-dimensional optical storage technology is a hot research direction for the development of high-density optical storage.

The applicant's previous patent application "A multi-dimensional optical storage disc and its data readout method", announcement date: 2012.07.04, announcement number: 102543110A, proposed the concept of "multi-dimensional optical storage", and disclosed a A method for reading data from a multi-dimensional optical storage disc. The multi-dimensional optical storage disclosed in the previous patent application refers to: processing recording pits with different depths and different angles on the recording layer of the optical disc to generate a multi-dimensional optical storage recording bit, and depositing multi-wavelength read-write materials on the recording layer, so that the traditional optical The stored binary two-dimensional records are converted into multi-ary multi-dimensional records, and more information can be stored on a single recording bit, thereby greatly increasing the storage capacity of the optical disc.

The previous application also discloses a data readout method for the above-mentioned multi-dimensional optical storage optical disc, specifically: focusing mixed laser light of different wavelengths on recording pits of different depths and angles on the optical disc, receiving reflected light from each recording pit, and according to each Identify the depth of the recording pit by the phase of the reflected light of the recording pit, identify the angle of the recording pit according to the polarization of the reflected light of each recording pit, and sort the laser light according to the amplitude of the reflected light of each recording pit to lasers of different wavelengths, combined with the depth of the recording pit and the angle of the recording pit and laser sorting results to decode the data stored on the disc.

However, the signal detection method in the data readout method of the multi-dimensional optical storage disc disclosed in the applicant's previous patent application still has defects and deficiencies: one is to detect the polarization state of the reflected light through the polarization detection module, and distinguish The different angles of the recording pits, the detection and calculation steps are complicated, and the operation is inconvenient; the second is that the angle range of the record symbol can be distinguished from 0-90 degrees, and the record symbol with an angle of 90-180 degrees cannot be distinguished; the third is that the detection device includes phase detection Module, polarization detection module, wavelength detection module and many other equipment, the detection device is complicated.

Contents of the invention

The object of the present invention is to provide a signal detection method for a multi-dimensional optical storage disc, which can distinguish between different depths and Angle, the angle range that can distinguish the record is 0° to 180°, and the depth is λ/4 to λ/2 (λ is the wavelength of the light source), which can significantly improve the signal detection rate of multi-dimensional optical storage, thereby greatly improving the performance of multi-dimensional optical storage storage density.

The technical solution adopted by the present invention to achieve the technical purpose is: a signal detection method of a multi-dimensional optical storage disc, wherein the discs of the multi-dimensional optical storage are processed with record characters of different depths and angles, and the laser light emitted by the incident light source passes through the beam splitter and The focusing lens is focused on the surface of the record, and the reflected light then enters the light intensity detector after passing through the focusing lens and the beam splitter; when the laser is focused on the center of the record, the light source is rotated 180°, and the light in the light intensity detector is read out The intensity changes with the angle of the light source; the angle of the record mark is distinguished by the angle of the rotating light source corresponding to the maximum value of the light intensity signal, and the depth of the record mark is distinguished by the average amplitude of the light intensity signal.

A signal detection method of a multi-dimensional optical storage disc, wherein the angle of the rotating light source corresponding to the maximum value of the light intensity signal is the angle of the record mark.

A signal detection method for a multi-dimensional optical storage disc. When different light intensity average values and different record symbol depths are simultaneously arranged in increasing or decreasing order into light intensity value arrays and record symbol depth arrays, the light intensity value arrays There is a one-to-one correspondence between the numerical values of the record depth sequence, and the value in the record depth sequence corresponding to the light intensity average value is the depth of the record.

A signal detection method for a multi-dimensional optical storage disc, the incident light source is 0° linearly polarized Gaussian light.

A signal detection method for a multi-dimensional optical storage disc, the signal detection method is used to distinguish the depth range of record characters from λ/4 to λ/2, where λ is the wavelength of the incident light source, and the signal detection method is used to distinguish record characters The angle range is 0°～180°.

Compared with prior art, the beneficial effect of the present invention is:

1. The present invention utilizes the principle that "when the angle of the incident light source is consistent with the angle of the record character, the light intensity of the reflected light is the maximum value", adopts the method of rotating the light source from 0° to 180° and reading the light intensity change information, and passes the light intensity signal The angle of rotation of the light source corresponding to the maximum value of is used to distinguish the angle of the record. Compared with the prior art method of detecting the polarization state of reflected light to distinguish the angle of the record character, the detection optical path is simple, easy to operate, and has high accuracy.

2. The present invention utilizes the principles of "the intensity of reflected light increases with the depth of the record", and "the magnitude of the detected reflected light intensity is in a cosine function-like relationship with the angle of the incident light source", by detecting the reflected light intensity and calculating the average Amplitude (arithmetic mean of maximum value and minimum value), using the average amplitude of reflected light intensity to distinguish the depth of the record. Compared with the prior art method of distinguishing the depth of the record mark by the reflected light intensity value at any angle, the detection accuracy is higher.

3. In the signal detection method provided by the present invention, the detection range is significantly increased, and the angle range that can distinguish the record is 0° to 180°, and the depth is λ/4 to λ/2 (λ is the wavelength of the incident light source), and the signal detection The efficiency is high, and the storage density of multi-dimensional optical storage can be effectively improved.

4. The signal detection method provided by the present invention only needs to detect the light intensity with a light intensity detection device, and can distinguish the depth and angle of the record symbol at the same time. Compared with the method in which multiple detection modules are used in the prior art to detect, the device is more efficient. For simplicity and easier operation, it has wider applicability.

Description of drawings

FIG. 1 is a schematic diagram of the structure of a single record of the multi-dimensional optical storage disc of the present invention.

FIG. 2 is a schematic structural diagram of a detection device used in the signal detection method for a multi-dimensional optical storage disc of the present invention.

Fig. 3 is a graph showing the variation of the reflected light intensity of a single record mark with the angle of the incident light source.

FIG. 4 is a graph showing the variation of reflected light intensity of record marks with different angles with the angle of incident light source.

FIG. 5 is a schematic diagram showing the curves of the reflected light intensity varying with the angle of the incident light source for multiple record marks with different depths.

In the figure: 1. Optical storage medium, 2. Recorder, 3. Incident light source, 4. Spectroscope, 5. Focusing lens, 6. Multi-dimensional optical storage disc, 7. Light intensity detector.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

The inventors of the present application found that: after the incident laser light is reflected by the surface of the record symbol, the magnitude of the reflected light intensity has a cosine-like relationship with the angle of the incident light source, and when the line deviation angle of the incident light is consistent with the angle of the record symbol, the reflected light The light intensity reaches the maximum value; when the line declination angle of the incident light is perpendicular to the angle of the record mark, the light intensity of the reflected light reaches the minimum value. For example: select record 1 (depth 162.5nm, angle 45°) for verification, focus the incident light to the center of record 1, rotate the incident light 180°, detect the change information of reflected light intensity, and get the result as shown in Figure 3 A graph showing the intensity of reflected light as a function of the angle of incident light. It can be seen from Figure 3 that the intensity of the reflected light varies with the angle of the incident light in a law similar to the cosine function, and when the incident light rotates to 45°, the intensity of the reflected light reaches the maximum value, and when the incident light rotates to 135°, the reflected light Light intensity is minimal.

In order to further verify the above rules, four recorders with a depth of 162.5nm and different angles were selected for verification. The four recorders are: recorder 2 (angle 30°), recorder 3 (angle 70°), recorder 4 (angle 120°) and record 5 (angle 180°), four curves of the intensity of reflected light changing with the angle of incident light are obtained as shown in Figure 4. It can be seen from Figure 4 that the incident light angles corresponding to the maximum values of the reflected light intensity of the four curves are 30°, 70°, 120° and 180° respectively, which correspond to the angles of the four record characters, so further verify the above Conclusion: When the line deflection angle of the light source is consistent with the angle of the record mark, the intensity of the reflected light reaches the maximum.

The inventors of the present application also found that: when the record depth is in the range of λ/4 to λ/2, the intensity of the reflected light increases with the increase of the record depth. For example: select a group of recorders with the same angle (both 140°) and different depths for verification. The four recorders are: recorder 6 (depth 162.5nm, 1/4 wavelength), recorder 7 (depth 200nm, About 1/3 wavelength), record mark 8 (depth 220nm) and record mark 9 (depth 325nm, 1/2 wavelength), get the change curve of reflected light intensity of record marks at different depths as shown in Figure 5. It can be seen from Figure 5 that the reflected light intensity of the four record marks with the same angle and different depths changes with the incident light angle in a cosine-like function, and all of them form the maximum light intensity value when the incident light is 140°, which further verifies the conclusions mentioned above. And it can be seen from Fig. 5 that the magnitudes of the reflected light intensity reflected by the record marks at different depths are obviously different, and the four curves form an obvious ladder shape. More specifically, record 6 (depth 162.5nm, 1/4 wavelength), record 7 (depth 200nm), record 8 (depth 220nm) and record 9 (depth 325nm), the average value of reflected light intensity is about 0.85mW, 1.15mW, 1.75mW, 3.85Mw. It can be seen that different reflected light intensity values correspond to different record depths, and a larger reflected light intensity value corresponds to a larger record depth, and vice versa. Therefore, when different light intensity values and different record depths are simultaneously arranged in ascending or descending order into the light intensity value array and the record depth array, the values in the two arrays are in a one-to-one correspondence.

The signal detection method of the multi-dimensional optical storage disc provided by the present invention uses the above-mentioned rules to realize the distinction of record characters of the multi-dimensional optical storage disc. Fig. 1 is a schematic structural view of a single record of the multi-dimensional optical storage of the present invention. The record 2 is an irregular geometric structure. The horizontal section of the record 2 is composed of a rectangle in the middle and two semicircles at both ends, and the rectangular As wide as the diameter of the semicircle. The length and width of different record 2 are fixed values (1.02um and 0.58um respectively), and the depth and angle are variable. The angle of record 2 refers to the angle between the long axis of record 2 and the scanning direction, and the range is 0 °-180°.

FIG. 2 is a schematic structural diagram of a detection device used in the signal detection method of a multi-dimensional optical storage disc of the present invention. The incident light source 3 emits a linearly polarized Gaussian laser with a linear polarization angle of 0°. After passing through the beam splitter 4 and the condenser lens 5, it is focused onto the multi-dimensional optical storage disc 6. After being reflected by the disc surface, it enters the laser beam through the focusing lens 5 and the beam splitter 4. Intensity detector 7, the light intensity detector 7 is used to detect the light intensity information of the reflected light.

The signal detection method of the multi-dimensional optical storage disc provided by the present invention is as follows: the laser light emitted by the incident light source is focused on the surface of the record character through the beam splitter and the focusing lens, and the obtained reflected light enters the light intensity detector after passing through the focusing lens and the beam splitting lens; When the laser is focused on the center of the record character, the light source is rotated 180°, and the information of the change of the light intensity in the light intensity detector with the angle of the light source is read out; the angle of the record character is distinguished by the angle of the rotating light source corresponding to the maximum value of the light intensity. The light intensity average is used to distinguish the depth of the record. The average light intensity is the arithmetic average of the maximum value and the minimum value of the light intensity. Using the average light intensity to distinguish the record depth can improve the accuracy of signal detection.

In the signal detection method of the multi-dimensional optical storage disc provided by the present invention, the method for distinguishing the angle of the record symbol is specifically: the angle of the rotating light source corresponding to the maximum value of the light intensity is the angle of the record symbol.

The signal detection method of the multi-dimensional optical storage disc provided by the present invention, the method for distinguishing the depth of the record symbol is specifically: arranging different light intensity average values and different record symbol depths into light intensity value arrays in increasing or decreasing order at the same time, recording When the character depth sequence is used, the values in the light intensity value sequence and the record depth sequence correspond one by one, and the value in the record depth sequence corresponding to the light intensity average value is the depth of the record.

In the signal detection method of a multi-dimensional optical storage disc provided by the present invention, the incident light source is preferably 0° linearly polarized Gaussian light.

The signal detection method of the multi-dimensional optical storage disc provided by the invention is used for distinguishing the depth range of λ/4 to λ/2, and the angle range of 0° to 180°.

The above is the signal detection method for multi-dimensional optical storage of the present invention, but the present invention should not be limited to the content disclosed in this solution and the accompanying drawings. Therefore, all equivalents or modifications that do not deviate from the spirit disclosed in the present invention fall within the protection scope of the present invention.

Claims (5)

1. A signal detection method of a multi-dimensional optical storage disc, the disc of the multi-dimensional optical storage disc is processed with record characters of different depths and angles, it is characterized in that: the laser light sent by the incident light source is focused to the record by a beam splitter and a focusing lens When the laser is focused on the center of the record character, the light source is rotated 180°, and the light intensity in the readout light intensity detector changes with the angle of the light source The information; the angle of the record mark is distinguished by the angle of the rotating light source corresponding to the maximum value of the light intensity, and the depth of the record mark is distinguished by the average value of the light intensity. 2 . The signal detection method of a multi-dimensional optical storage disc according to claim 1 , wherein the angle of the rotating light source corresponding to the maximum value of the light intensity is the angle of the record symbol. 3 . 3. The signal detection method of a kind of multi-dimensional optical storage disc according to claim 1, characterized in that: different light intensity average values and different record depths are simultaneously arranged in ascending or descending order respectively into light intensity value series, When recording the character depth sequence, the values of the light intensity value sequence and the record depth sequence correspond one to one, and the value in the record depth sequence corresponding to the light intensity average value is the depth of the record. 4. A signal detection method for a multi-dimensional optical storage disc according to claim 1, wherein the incident light source is 0° linearly polarized Gaussian light. 5. The signal detection method of a multi-dimensional optical storage disc according to claim 1, characterized in that: the depth range of the signal detection method for distinguishing record characters is λ/4 to λ/2, and λ is the incident light source The wavelength used by the signal detection method to distinguish the record marks ranges from 0° to 180°.

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