JPH03504768A - Interferometer system for measuring distance and shift movements, especially of moving components - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Distance or shift, especially of moving components Interferometer system for measuring motion The present invention particularly relates to an interferometric system for measuring distance or shifting movements of moving components. A system comprising a laser beam source and a reference beam that connects the light emitted from the laser beam source to a reference beam. used to split the measurement beam into a single mode beam and a measurement beam, in which case the measurement beam is - Tune-out lenses guided by waveguides from which reference adjustments are made; resides at least partially within the surrounding medium of the gas phase via a tune-out lens system and is configured to reach the measuring section guided by the movable measuring mirror. The spectrometer, the reference beam guided through the reference section, and the return beam from the measurement section. the recombiner in which the interference of the measured beams takes place; a detection device for analyzing at least one interference signal that is Regarding formal matters.

Interferometer systems of this type can, in principle, also be used with moving components. In particular, distance measurements, shift movement measurements, and even position or position variations of machine components. Suitable for use in measurements. However, especially in the industrial field, known single frequency - interference When using a measurement system, a lateral 3D interference pattern that is extremely difficult to adjust is generated. It has been demonstrated that problems arise when observed.

Furthermore, one of the unavoidable problems in practice is that when returning from the measurement section, Distortion of the wavefront or wavefront in the measurement beam. This kind of wavefront distortion This can be caused by, for example, stripes in the air (schlieren), and especially by the system in question. When the system is used in an industrial field, it is important to avoid contaminants (optional particles) in the air in which the measurement beam propagates. (e.g., oil vapor) or the inaccuracy of the optical components used. the last light mentioned Regarding the imprecision of chemical components, if necessary, replace the components with other suitable methods, even if they are expensive. It cannot be avoided by replacing the ingredients with other ingredients (although this does not mean that 6X requires a significant increase in the cost of the entire interferometer system.

Moreover, in this case, wavefront distortion caused by the atmospheric conditions that occur in practice is still avoided. I can't do that.

When such wavefront distortion occurs at a known single frequency, the observed three-dimensional This will cause the interference pattern to fluctuate, leading to erroneous measurement results.

Furthermore, this wavefront distortion occurs when the measurement beam and reference beam have slightly different frequencies. For a known double-layer wavenumber-heterodyne interferometer in which a beat frequency is observed between In other words, this type of wavefront distortion has undesirable effects even when , no matter how small the deviation from the ideally accurate adjustment value may be. However, we try to evaluate the quality of the interference, i.e. against the signal background. The modulation stroke of the oscillatory interference signal will be reduced.

Furthermore, length measurement is performed using a single mode waveguide (monomode - glass fiber). Interferometers of this type are also already known. Such a monomode - glass fiber Inside, light propagates with well-defined wavefronts. In a known interferometer, for example Monomode - Light originating from a glass fiber enters the measurement zone through a single lens. The light retro-reflected by a flat mirror that is tuned out during the After passing through one lens, the measurement beam is sent back to another interferometer using the same glass fiber. A flat measuring mirror is used that reflects back the light. Some of the light reflected from the light source enters the glass fiber originating from the light source and is fed back into the light source. However, this type of interferometer uses a flat measurement mirror. Based on sensitivity to tipping, measure in centimeters or larger. It is not suitable for use in simulated measuring sections, and in this case the light is reflected back onto itself. The measuring beam is transmitted into the laser beam source. Furthermore, due to field tests, It has been revealed that laser diodes are particularly sensitive to retroreflected light. The retroreflected rays in this case are therefore particularly critical and therefore undesirable. I have to say that this is not a good thing.

Therefore, the problem of the present invention is to eliminate the need for requiring much effort and expense at the site of use. laser beam from the interferometer into the laser source. The return of the system is virtually avoided and the distances that occur especially in industrial applications are avoided. A separation or shift movement (typically a distance of centimeters or more) A compact, low-cost dryer that can accurately and reliably detect even motion. The point is that it provides an intervening measure.

According to the measures of the present invention proposed to solve this problem, the second single-mode waveguide A tune-in lens or tune-in lens system separate from the body is provided, This tune-in lens or tune-in lens system can be used as a retro reflector. The measurement signal that is retro-reflected with the beam shifted by the configured measurement mirror is 2 single mode - used for tuning into waveguides.

In the interferometer according to the invention, the measurement beam is not reflected back to itself from the measurement mirror. , separate tune-in lenses (or one lens system with offset beams) a second single mode-guide via multiple tune-in lens devices (synthesized as It is tuned into the wave body. Even if such structural measures are taken, For example, it is certain that the interfering beam is not fed back into the laser source from the interferometer. avoided, and therefore especially if its radiation fluctuates delicately with respect to the feedback beam. A decisive advantageous effect is produced in laser diodes that this place (i.e., at least within a given plane of incidence) In a given angular range of the beam, it is possible to reflect the beam with a deviation parallel to itself. Unlike a flat mirror, there is no need for adjustment during adjustment. Occurs upon lateral displacement of the retroreflector without causing any disadvantages Select appropriate tune-out and tune-in lenses for beam deviation fluctuations. This problem can be easily overcome if the second single-mode waveguide Even if light is applied to the tune-in lens, the waveguide returning from the measurement section is Tune-in has been demonstrated to be sufficiently non-critical. Furthermore, advantageous This retro reflector is configured as a triple mirror or triple prism. Since the reflector has a tilt-invariant characteristic (the position of the reflector changes when the position changes), (the reflected beam remains parallel to the incident beam), especially when the measurement interval is long. This has advantages over conventional flat mirrors in some cases. Triple mirror has a predetermined solid angle It has the property of reflecting a bundle of light rays incident on it parallel to itself.

According to the invention, the cost of adjustment in the range of the measurement beam can be reduced by using the conventional light guide. This can be significantly reduced compared to the case of an interferometer that does not use.

In this case, if enough light is tuned into the second glass fiber, This interferometer is kept in a precisely calibrated state (although there are other prerequisites). must be relatively easily preconditioned), which also means that As already mentioned, especially for retroreflectors that always reflect the beam in parallel. Depending on the characteristics and proper dimensional design of the lens, 0 cannot be particularly critical. The interferometer according to an advantageous embodiment of the invention tunes out the measurement beam therefrom. The first single mode waveguide and the second single mode waveguide are placed in the measurement section, respectively. They are arranged so that they are located parallel to each other in the end region on the opposite side. each separately The tune-in lens, tune-out lens, and waveguide are correct relative to each other. For fine tuning, a single mode waveguide and a second waveguide are used to tune out the measurement beam. At least each end area facing the measurement section of the single-mode waveguide is connected to a common fixed on the carrier, and in this case, tune-in lenses and tune-out lenses. It is particularly effective to fix the lenses to this carrier.

Further, as in the present invention, the measurement beam may be a second glass fiber or monomorphic beam. If tuned into the waveguide, it is fed back from the measurement section. Completely eliminates undesirable waveguide effects caused by wavefront distortion in the measurement beam. or at least significantly reduce it. In other words, what will happen? , this type of wavefront distortion is caused by the intensity outside the optical axis (second group) on the focal plane of the tune-in lens. centering on the diffraction-based focal point where the las fiber entrance site is located. (intensity outside the diameter) and does not reach the second waveguide, i.e. This is because it is faded out by the needle guide. Therefore, this sea urchin moth Behind the waveguide, i.e. behind the plane of incidence in the second single mode waveguide, the wave In order to remove the head distortion, it is necessary to create a measurement with an almost ideal wave front that has been cleaned. A constant beam is obtained which is then interfered with a reference beam. like this The interference signal obtained by It can be done. Since a single mode waveguide is used in this case, The wavefront inside the waveguide is in an almost ideal state, and the waves generated along the measurement section are In this type of waveguide, head distortion simply reduces the tune-in into the waveguide. Advantageously, the body is configured as a waveguide that diffuses on the wafer; In the case of The interference signal originating from the reference beam and recombining device is integrated on the wafer. It is particularly effective to guide the waveguide into a single-mode waveguide that is diffused within the same wafer. Ru. If such an integrated construction style is adopted, most of the optical elements The reference beam and wavefront distortion can be reliably adjusted in advance. In the interferometer system according to the invention, most Since only integrated optical components are used, it is also cheaper than conventionally known optical components. Advantageous results are obtained compared to other interferometers. Interference with waveguides diffusing within the wafer Although it certainly belongs to the category of technology that is publicly known, it is not publicly available. In the currently known integrated interferometer, the measurement beam generated from the waveguide is A flat mirror placed at a small distance from the radiating site allows for partial synchronization. This known interferometer uses a flat measuring mirror to It is only usefully used to measure very small shifting movements; Therefore, it seems out of the question to use this in the industrial field. Moreover, this well-known drying In the interpolation meter, it is possible to avoid undesirable feedback into the light source as described above. I can't do it.

In the present invention, the spectroscope and the recombiner are each configured as separate optical elements. Needless to say, it is possible, and in some use cases, to In some cases, it may be especially advantageous to take the following measures. The above-mentioned method for integrating optical elements In order to make possible a simple and perfect adjustment in the embodiment, the light source A tune-out lens (or lens system) that directs the light generated from the lens into the surrounding medium. and the retroreflector between the tune-in lens (or lens system). up to the measuring section extending over the length of the measurement range, and possibly even to the recombination located within each single-mode waveguide. In this case, the spectrometer It is particularly effective if the recombination device is formed by a waveguide coupler.

Other advantages and details of the invention are shown below in the accompanying drawings. 1, 2 and 3 show an interferometer system according to the present invention. Each embodiment of the system is shown schematically.

The interferometer system shown in FIG. 1 is advantageously configured as a laser diode. It has a laser beam source (1) made of The light is a single mode light that is diffused on a wafer (3) made of lithium niobate. - In the spectrometer (B) tuned into the waveguide path (2), the light is initially guided The measurement beam transmitted in the wave body path (4) and the integrated arrangement in the extending wafer (3) The reference part (4) is guided through the mirror (6) to the recombining device (A). This measurement beam is then emitted from the waveguide (4) and split into a beam and a , are calibrated by a tune-out lens (7). By the way, don't worry about the measurement interval. The phase is exposed to the surrounding medium (often air), e.g. Reaching the retroreflector (8) as a triple mirror fixed on the carriage of the tool It extends until This retroreflector (8) aligns the optical axis of the measurement beam in parallel. After shifting, the beam is sent back, but at that time, the side of the retroreflector (8) The direction of the measuring beam, which is fed back by its displacement or its tilting motion, is varied. There is no translation, only a translation on a non-critical scale.

According to the invention, the measurement beam returning from the retroreflector (8) is provided separately. A tuned tune-in lens (9) allows the tuning into the second single mode waveguide (11). Because the laser beam is tuned in, the interfering laser beam is inside the laser diode (1). This can be avoided.

In the embodiment of the invention shown in FIG. single mode - in the focal plane surrounding the focal point of the lens (9) in the waveguide (11) The arranged surface (10) is located outside its focal range and is caused by wavefront distortion. It functions as a unique guide to fade out the intensity of the signal. In this case Since a single mode waveguide is used, the waveguide (1 1) The wavefront of the measurement beam tuned in is kept in an almost ideal state. Therefore, the wavefront distortion induced by the retroreflector (8) along the measurement section is simply The interferometer system according to the invention therefore only reduces the quality of the tune-in. To tune the waveguide path, simply diffuse a sufficient amount of light within the wafer (3). (11), this method is not critical. Each beam returned from the rectifier (8) to be parallel to each other is focused in the focal plane at the same point and then all beams hit the waveguide (11). This is obvious because of the fact that In the illustrated embodiment, the second waveguide (1 1) Tune-in within the range of millimeters around the lens axis This is typically done for the beam hitting the tune-in lens in Therefore, no particularly critical conditions arise.

The measuring beam fed back from the measuring section is configured as a spectrometer (A). In the recombining device, the beam is subjected to interference processing together with the reference beam guided into the reference part (5). 6 The interference signal is then detected by each detector (12a) to (12d), and 9 used in the illustrated embodiment evaluated in an electronic evaluation circuit not shown is a single-frequency interferometer, in which case the direction of movement of the retroreflector (8) is In order to obtain information about A polarizing device that is To do this, the polarized light must be placed in front of the retroreflector (8). A phase delayer (13) is incorporated, which functions in conjunction with the The device creates a 90° relative phase difference between equivalent optical devices. recombination device f The two mutually complementary outputs provided in (A) are located within the wafer (3). coupled to a polarization spectrometer (17) via waveguide paths (14) to (15) diffused by The output of the polarization spectrometer is output from each of the photoelectric detectors (12a) to (12a) described above. 2d). These photoelectric detection @(12a) to (12d) are Interfering signals are received shifted in a relative phase relationship, and a single signal is generated from each received signal. In addition to the shift movement stroke of the retroreflector (8), the shift direction is also clearly defined. It can be stipulated. Furthermore, two complementary outs in the recombiner fjl(A) By detecting the intensities of topputs (14) and (15), normal homodyne The operating method is subject to various influencing factors (mechanical and electrical engineering) that can lead to measurement errors. Intensity changes due to thermal drift in child engineering, light source intensity fluctuations, and slight misadjustments. fluctuations) can be eliminated, so the intensity fluctuations can be considered as these influencing factors. Is this due solely to fluctuations in the retroreflector (8) or is it actually due to changes in the retroreflector (8)? It will also be possible to confirm whether the problem is caused by exercise. i.e. measurement beam After the merging of the interfering signal beam and the reference beam, only one interfering signal beam is used. rather than a second output in the spectrometer that provides a complementary interference signal. will also be available for use. All that thus causes the intensity to fluctuate unfavorably. While the influence value of acts on both complementary signals in the same way, the actual Only the process changes the interference pattern and thus the relative intensities in both complementary signals. Even when a homodyne-laser interferometer is used, Similar to the case using a two-frequency device (heterodyne method) described below, the mechanical system It is possible to accurately grasp the stopped state of the stem. In this way, the measurement beam single mode - tuned into the waveguide and logically associated with this waveguide. Making full use of the unibu guide effect and improving the state of the wavefront in the single mode waveguide. By making it ideal, it is practically satisfactory even under industrial conditions. Obtain a defined complementary interference signal without using This guarantees that the evaluation can be performed with high reliability.

The interferometric system according to the invention operates in principle in a heterodyne manner; In this case, two slightly different optical frequencies are used. used in the present invention The advantage of lithium niobate material is that it can also be incorporated into acousto-optic modulators. In this case, to obtain the optical frequency shifted by the acoustic frequency, For this purpose, a modulator deposition process is performed. In this heterodyne specification interferometer, , it is necessary to use four charging elements (12a) to (12d) as in the example described above. All you need to do is install one detection photodiode instead. Furthermore, in this embodiment, a phase extender (13) and a polarizer which respond to the degree of polarization are used. It is also possible to omit the optical spectrometers (16) and (17).

A cluster type structure in which light is guided into each mode-waveguide path within the wafer (3). By adopting this structure, a compact structure can be obtained, while at the same time It is assumed that the beam and the measurement beam have ideal wavefront conditions within the single mode waveguide. Based on this, it is possible to realize an extremely effective interference process between both beams. come. However, in this example, most of the optical elements are adjusted in advance. It is possible to

In an advantageous embodiment of the invention, a reference section (5) extending into the wafer (3) is provided. The length of each waveguide (4), (11) extending within the wafer (3) is set equal to the total of the interferometer waveforms. The influence of temperature (c) (3) is also almost completely avoided. Special as a light source The reason why the laser diode (1) is suitable for this is that it requires only a small amount of space. It is also said to be advantageous in terms of cost.

Measured values by this interferometer are expressed in units of airborne wavelengths existing within the measurement interval, The atmospheric wavelength itself depends on the frequency of the light and the refractive index of the surrounding medium (air in most cases). This airborne wavelength can be continuously detected by a proprietary device. is desirable. If the frequency of the light source can be obtained as a known number, in order to find out the atmospheric wavelength, For this reason, it is sufficient to measure the refractive index. In its simplest implementation, an empty The refractive index can be detected using the so-called parametric method that measures the temperature, humidity, and atmospheric pressure of the air. It can be done. In addition, let's also relate the frequency of the light source to this aerial wavelength measurement. In this case, a concrete example for measurement (etalon) placed under the same environmental conditions as the measurement section is used. ) can be compared. In one example of such an implementation, the light originating from the light source is It is necessary to branch out from the original interferometer, and in order to achieve this most easily, A spectrometer (C) placed immediately after the light source in the optical path is used.

The measurement beam is first guided into the single mode waveguide before the measurement section in the surrounding medium. and then guided into the measurement zone using a tune-out lens. If the I can do that.

In addition to the aforementioned lithium niobate, suitable materials for use in wafers include: Examples include glass and gallium arsenide.

Furthermore, in addition to implementations in which single mode waveguides are integrated on wafers, glass fiber An embodiment using the waveguide as a single mode waveguide is possible and is shown in FIG. This is one example.

The interferometer shown in the embodiment of FIG. The triple mirror (8) is used to detect motion, in which case the triple mirror (8) is the movable component. It is particularly advantageous if it is fixed directly on top. Laser diode (1) The laser beam emitted from is first tuned into the glass fiber (2). from there into the spectrometer (B) as a coupler, in which the measurement is carried out. Glass fiber belonging to the fixed part (4) and glass fiber belonging to the reference part (4) 5) It is divided into Furthermore, tune-out lenses ( 7) and reaches the original measurement section extending into the surrounding medium, this light is triple-mimic. feedback parallel to itself with the beam axis shifted by the mirror (8). According to the present invention, the measurement beam fed back is provided separately. A tune-in lens (9) is connected to the second single mode waveguide (glass is tuned into the fiber 11).

In the embodiment shown in FIG. 2 as well, the The end areas of the glass fibers (4) and (11) are arranged parallel to each other. If this measure is taken, the triple mirror (8) system will be The desired effect is always achieved without the need for expensive deflection devices during foot movements. In general, the measurement beam fed back from the measurement section is connected to a glass fiber ( 11) is achieved. Glass fiber (4) and Advantageous embodiment for precisely setting the relative orientation at each end of (11) , these ends are fixed to a common carrier (18) and furthermore in this case , glass fiber with tune-out lens (7) and tune-in lens (9) - To ensure that relative adjustments are made to (4) to (11). , the carrier (18) is arranged so that it also carries each lens (7), (9). It is convenient to configure this.

Tune-in lenses (9) and tune-out lenses (,7) are advantageously equivalent. As such, it is also specifically constructed as lenses with equal focal lengths. child Particularly suitable for use as tune-in and tune-out lenses for species of Suitable are those which can be fixed directly to the carrier (18) via their flat connecting surface. It is a gradient-index lens that can be used.

The light fed back into the glass fiber (11) from the measurement section and the reference section The light guided into the glass fiber (5) is recombined within the coupler (A). . Advantageous between equivalent light values (volatization) for detecting the direction of movement of the measuring carriage The phase deviation, which is set to a value of 90”, is due to total internal reflection within the triple prism. Alternatively, by using a quarter-wave plate that provides birefringence, which is not shown in Figure 2. You can get it. The interference signals at both outputs of coupler (A) are polarized. Depending on the polarization state perpendicular to each other, using a light spectrometer or a spectrometer and polarization manipulation, Cl2a, 12b, 12c, 12d), each separately detectable, in Fig. In the example shown, the beam splitting according to the polarization state is performed using two spectrometers ( AL''), (A2') and placed in front of each detector (12a) to (12d). This is done through four polarizing filters (26a) to (28d). These two If a polarization spectrometer is used instead of the spectrometers (Al') and (A2'), of course However, the polarizing filters (26a) to (26d) can be omitted.

Alternatively to the above example, the format shown in Figures 2a and 2b may be used. It is also possible to perform signal division according to the degree of polarization (as shown in these figures). In the variation described above, the arrangement form in front of the recombining device A is the same as that of the embodiment shown in FIG. equal). In the example shown in Figure 2a, both outputs at the recombiner (A) A lens (27) is used which is placed just in front of the target area. This lens ( Both beams imaged by 27) first reach the polarization spectrometer (A3), and from there It is guided to four detectors (12a) to (12a). Also, the changes shown in the second brM In this embodiment, two spectrometers (A1') and (A 2”) is omitted, and the light is finally passed through polarizing filters (26a) to (26d). In order to achieve three-dimensional signal splitting according to the degree of polarization, it is necessary to The diverging reflection cones (28) and (29) composed of output fibers are It's being used. In this case, each detector (12a) to (12d) has one It is connected to an electronic evaluation circuit (19).

As is clear from Figure 2, the light originating from the light source (1) extends into the surrounding medium. Each single mode is guided through the waveguide (glass fiber) until it reaches a fixed section. , the undesirable influence of interfering rays is largely excluded and furthermore the recombination in the coupler (A) is In this case, the measurement part - glass fiber (11) and the reference part - glass fiber – (5), the wavefront is in perfect condition, resulting in outstanding interference signal characteristics. Guaranteed. In this case, the wavefront distortion that occurs in any case is caused by the feedback from the measurement section. When tuning the measured beam into the glass fiber (11) It is erased by the Unibu Guide effect obtained.

Various known interferometers split light into a measurement beam and a reference beam. A spectrometer for simultaneous interference of the measurement and reference beams Also used as a recombination device. However, in an advantageous embodiment of the invention, the light In order to completely exclude the reaction of the laser beam to the source, a spectrometer (coupler B) and The recombining device (coupler A) is constructed as a respective separate optical element.

No matter what possible temperature changes occur, there should be no correlation between the reference part and the measuring part. In order to avoid relative length variations, an advantageous embodiment of the invention provides Distance within the glass of fibers (4) and (11) and glass of glass fiber (5) The inner distance is set to the same value.

Dimensional design of tune-in and tune-out lenses (especially their focal length settings) There are many points to be careful about when using a tune-in lens. and what can be achieved when adjusting the angle in the optical axis of the tune-out lens. accuracy, diameter accuracy, spread accuracy of light rays generated by diffraction within the measurement section, and retrorelation accuracy. The main points to keep in mind are the accuracy of the reflector angle. In this case, metric units or If we want to detect the shift stroke in the The diameter of the waveguide requires precision on the order of micrometers, and Regarding the typical opening angle of the reflection cone, from 1 mm to 10 mm, advantageously 2 m Experiments have shown that a lens focal length of value from m to 4rrLm is required. has been done.

In the embodiment shown in FIG. 3, each of the eleven components of the interferometer system according to the present invention is Identical if equal or approximately equal to that in the embodiment according to FIGS. 1 and 2. It is marked with a reference sign. The embodiment shown in Fig. 3 is different from the embodiment shown in Fig. 1. The main point is that in the case of the embodiment shown in FIG. To obtain the interference signal, two different polarization operations are performed, one of which is While the degree of polarization is advantageously phase-stretched by 90° from the other degree of polarization, as shown in FIG. In embodiments, it may be sufficient to utilize unpolarized or simply polarized light. The desired purpose is achieved and the direction of movement of the retroreflector (8) is known. The out-of-phase interfering signals that are It is about to be exposed in each evaluation channel.

The spectrometer (20) divides the reference beam of the reference section (5) into two separate reference partial beam sections. Divide into (24) and (25). Similarly, the spectroscopic unit (21) also performs measurement. Measuring beam tuned into the second single-mode waveguide (11) from a fixed section is divided into two measuring partial beams, and these partial beams are connected to a waveguide (26 ), (27). 1 in each of the double coupling devices (A1) and (A2) The two measurement sub-beams and the reference sub-beam are interferometrically processed. determined by this example. The fixed point is that the measurement partial beam in the recombiner (A1) The relative phase relationship between the beam and the reference partial beam and the relationship in the recombiner (A2) the relative phase relationship between the measurement partial beam and the reference partial beam, respectively. The detectors (12a) and (12c) are different from each other. ) and the detectors (12b) and (12d). They are placed in a phase-shifted state with respect to each other.

Reference part beam and measurement part in two recombiners (A1) and (A2) Because this creates different relative phase relationships with the beam, measurement The constant partial beam section (26) has a phase that can induce a phase shift of, for example, 90@. A trim device is provided. The light propagation line shown in Figure 3 is can be realized as glass fibers or as optically integrated structures. Ru. In optically integrated configurations, the desired phase trimming is achieved. In order to I can do that. In fiberglass embodiments, for trimming. A twistable glass fiber loop is used (this effect has recently been Lee-Phase: It became publicly known in connection with Berry-Phase. ).

Operation with multiple channels well separated from each other as shown in Figure 3 If the The polarization-dependent effects on reflection and total internal reflection are noncritical and It is guaranteed that the conditions imposed will become even more lenient. Furthermore, they are fully divided into each other. When carrying out operation with multiple channels, the reference beam is divided into three or more reference partial beams. At the same time, the measurement beam is also divided into three or more measurement partial beams, These reference partial beams and measurement partial beams are phase-trimmed as appropriate. This is especially easy if interference processing is performed in different recombiners after in a similar form, yet phase-shifted relative to each other on the desired scale. It becomes possible to obtain interference signals.

Note that the interferometer according to the present invention can be used not only for visible light but also for example for infrared light. Needless to say, it can function effectively even if

Brief description of the drawing 1...Laser beam, 2...Single mode waveguide (path), 3...Wafer, 4...Waveguide, 5...Reference part, 6...Mirror, 7...Tune-in lens Auskoppelinse, 8・--Retroreflector, 9・- ・Tune-in lens (Einkoppeilinse), 10... - side, 11--.

Single mode waveguide, 12a to 12d... photoelectric detector, 13... phase extender, 14, 15... Waveguide, 16, 17... Polarization spectrometer, 18... Carrier, 20...Spectroscope, 21...Spectroscopy unit, 24/25...Reference partial beam 26...Measurement partial beam, 26a-26d...Polarizing filter, 27. ・・Lens, 28・29・・Reflection cone, A-A1・A2・・Recombination device, A 3...Polarization spectrometer, Al', A2', B-C... Spectrometer.

Fig, 2 international search report mlm-1111, PCT/EP 90100423 International Search Report

Claims (1)

[Claims] 1. Interferometer system especially for measuring distance or shifting movements of moving components a laser beam source, and the light emitted from the laser beam source as a reference beam. used to split the measurement beam into a single mode conductor. A tune-out lens or tuner that is guided by a wave body and performs collimation adjustment from there. extending at least partially into the surrounding medium of the gas phase through the lens system; spectroscopy configured to reach a measuring section guided by two movable measuring mirrors. the reference beam guided through the reference section and the measurement section returned from the measurement section. A recombining device in which constant beam interference occurs and a recombining device generated from the recombining device. and a detection device for analyzing at least one interference signal. in which a second single mode waveguide (11) and a separate tune-in lens (9) A tune-in lens system is provided, and this tune-in lens system is provided. The tune-in lens system is configured as a retroreflector (8). The measurement signal retro-reflected by the mirror with the beam shifted is transferred to a second single-mode conductor. An interferometer system characterized in that it is used for tuning into a wave body (11). stem. 2. An interferometer system according to claim (1), from which a measurement beam is tuned. The single-mode waveguide (4) and the second single-mode waveguide (11) are Characteristically, they are located parallel to each other in the end range on the side facing the measurement section. interferometer system. 3. In the interferometer system according to claim (1) or (2), the tune-out The lens (7) and the separate tune-in lens (9) are configured substantially identically to each other. An interferometer system characterized by: 4. In the interferometer system according to claim (1) or (2), triple reflex The reflector is configured as a retroreflector (8) in a manner known per se. An interferometer system featuring: 5. In the interferometer system according to any one of claims (1) to (4), The light emitted from the source (1) passes through a tune-out lens in the surrounding medium. Retro reflex between lens system) (7) and tune-in lens (lens system) (9) (8) and possibly even each single mode conductor. The rear range of the recombiner (A) located in the wave bodies (2), (4), (5), (11) in this case the spectrometer (B). and the recombining device (B) is formed by a waveguide coupler. interferometer system. 6. In the interferometer system according to any one of claims (1) to (5), The optical device (B) and the recombiner (A) are each configured as separate optical elements. An interferometer system characterized by: 7. In the interferometer system according to any one of claims (1) to (6), each Single-mode waveguides (2), (4), (5), and (11) are each made of glass fiber. An interferometer system characterized by comprising: 8. In the interferometer system according to any one of claims (1) to (6), each Single-mode waveguides (2), (4), (5), and (11) are expanded within the wafer, respectively. An interferometer system characterized in that it is configured as a dispersing waveguide. 9. In the interferometer system according to any one of claims (1) to (8), Single-mode waveguides (2), (4), (5), (11) of the interpolator and the spectrometer (B) The bonding devices (A) are each integrated on the same wafer. interferometer system. 10. In the interferometer system according to claim (8) or (9), It is noted that crystalline lithium niobate (LiNbO3) is used as the material. An interferometer system with a special feature. 11. In the interferometer system according to any one of claims (1) to (10), , the spectrometer (B) and the recombiner (A) in the single mode waveguides (4), (11). The total measurement beam distance extending between and within the single mode waveguide (5) An interferometer system characterized in that the distance of a reference interval is set to an equal value. Mu. 12. In the interferometer system according to any one of claims (1) to (11), , an interferometer system characterized in that the light source (1) is composed of a laser diode. stem. 13. In the interferometer system according to any one of claims (1) to (12), , a single-mode waveguide (4) and a second single-mode waveguide to tune out the measurement beam. At least each end range facing the measurement section of the waveguide (11) has a common key. An interferometer system, characterized in that it is fixed on a carrier (18). 14. The interferometer system according to claim (13), wherein the tune-in lens (7 ) and a tune-out lens (9) are fixed to this carrier. interferometer system. 15. Tune-in lens (system) (7) and tune-out lens (system) (9) are each in the range from 1 mm to 10 mm, preferably from 2 mm to 4 mm. An interferometer system having a focal length. 16. In the interferometer system according to any one of claims (1) to (15), , the tune-in lens (7) and tune-out lens (9) are gradient tones. An interferometer system characterized by being configured as an index lens. 17. In the interferometer system according to any one of claims (1) to (16) , the retroreflector (8) is a movable component, in particular a linearly shiftable measuring stage. An interferometer system characterized by being directly fixed to the lidar. 18. In the interferometer system according to any one of claims (1) to (17), , this interferometer system works at only one optical frequency (homodyne operation); detecting the signal strength of two mutually complementary interference signals originating from the coupling device (A); At least two photoelectric detectors (12a), (12c) to (12b), (12d ) is provided. 19. An interferometer system according to claim 18, wherein two mutually perpendicular interferometers are provided. Light containing two polarized components is used; Prior to recombining the measuring beam and the reference beam in the combining device (A), both polarizations are inducing a phase shift between the components corresponding to a predetermined phase amount, advantageously a phase amount of 90 degrees; A device (13) is provided for causing the recombination device (A) to Each output section (14) to (15) outputs the partial beam intensity to each photoelectric detector. The output detected by the detectors (12a), (12b) to (12c), and (12d) An interferometer characterized by being provided with polarization spectrometers (16) to (17) system. 20. In the interferometer system according to any one of claims (1) to (18), , a reference beam guided in one single mode waveguide with at least two partial references. A spectroscopic unit is provided to split the beam into beams; At least two measurement beams are tuned into the second single mode waveguide. A separate spectroscopic unit is provided for splitting into partial measuring beams; Interference is performed on one partial reference beam and one partial measuring beam, respectively. At least two recombining devices are provided for recombining the individual The relative phase relationship of the partial reference beam and partial measurement beam in the recombiner is An interferometer system that is uniquely different. 21. In the interferometer system according to claim (20), in each recombination device, determine the different relative phase relationships between the partial reference beam and the partial measurement beam. phase in at least one partial reference beam and/or partial measurement beam in order to An interferometer system characterized in that a trim device is arranged.