JPS62502702A - Interferometrically selective amplitude modulation spectrometer - 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] Interferometrically selective amplitude modulation spectrometer Technical field FIELD OF THE INVENTION The present invention relates to optical machines, and more particularly to spectrometers that utilize interferometrically selective amplitude modulation.

Background technology The slit spectrometer is the most common of all types of instruments used in the field of spectroscopy. It is something that can be passed through. Basically, any slit spectrometer uses a parallel beam of light. The entrance slit installed in the focal plane of the collimator to be formed, and the prism or diffraction grating a diffusing element, an exit lens, and a wave dispersion element installed at the focal plane of the exit lens. (1972) ``Methods and applications of spectroscopy'' published by Nauka, Moscow, 8, N. Zaidel, G.V., 0strovsky.

Yu, 1.0strovsky co-author)).

The resolution and transmission of these spectrometers are inversely proportional to the width of the slit. slit is narrow If so, the resolution will be high and the transmittance will be low, and vice versa. Moreover, diffraction Because the slit cannot be made infinitely narrow, the resolution of the diffusive element To increase the power, it is necessary to use a long focus collimator. Therefore, the average spectral The length of the meter may be 1.5 to 2 m, and in the case of high-precision instruments, the length may be 6 m or more. It's sato.

Two fundamentally new types of spectrometers that use interference and eliminate slits have recently been developed. Proposed. One is Fourier spectrometer and the other is interferometric selective amplitude modulation (Hereafter, it will be referred to as SISAM, and first, the transmittance of the spectrometer, and therefore the sensitivity, will be doubled or tripled.) Ru. Second, the speed at which information is acquired has doubled or tripled, allowing spectroscopic analysis to be completed in a very short time. It becomes possible to complete. Third, regardless of the focal length of the entrance collimator and exit lens, Rather than realizing the theoretical resolution of dispersive elements, the spectrometer can be reduced by a factor of tens or even hundreds. This makes it possible to make it smaller and lighter.

Fourier spectrometer (e.g. 1960 J. Phys. Rad, 21.64 5.

J, Connes) along the axis of the interferometer in the vicinity of the zero-difference position of the interfering beam. It is a Michelson interferometer with a single movable mirror. This spectrometer records It has the disadvantage that the transmitted signal must be decoded by a computer. Besides, this spectrometers are sensitive to changes in light intensity during recording, and their mirror controls The mechanical system for the tool is complex and sensitive to mechanical interference; The spectral interval of action is limited by the range of transmittance of the base layer of the semi-reflective mirror. .

SISAM is a component that is positioned so that interference occurs only in the vicinity of one wavelength. It is a dual-beam interferometer with two arms with diffused elements.

The interferometric method of selection by wavelength consists in the periodic variation of the path difference of interfering light beams. Ru. The variable of the emitted light flux input to the light receiving/measuring circuit is the light intensity at the interference wavelength. is a function of

The disadvantage of all prior art SISAMs is that they require a lot of equipment to adjust and operate the device. Interference accuracy of 7 to 12 degrees of freedom is required for the components. This thing is , all angles toward the next are accurate, and it travels to a fraction of a wavelength. means that it is necessary.

Even precision equipment must have a sufficiently high degree of static and dynamic stability against mechanical interference. It is clear that this is impossible. Adjustment of such equipment is very complicated. It is a difficult task. This scanning system is so complex that the current scanning limit is hundreds of times the resolution interval, or more than about 10 people for the range of the visible spectrum. Can not.

Furthermore, the spectral range of most SISAMs is within the transmission band of the beam splitting mirror. limited by. In all known SISAMs, the frequency of the modulated signal is The wave number and phase change during the scanning of the spectrum. Which is synchronized detection of registered signals? This means that the output cannot be used. Moreover, the modulated frequency is 10 It cannot exceed 0 Hz, which prevents rapid analysis. These machines The size and weight of the instrument are mainly due to this complex scanning system. However, the known SISAM is much more accurate than the slit-type spectrometer. It becomes very expensive.

For example, one of the known SISAMs is Rev, d'Opt, 34, 1.1956. ) uses the properties of a symmetrically drawn diffraction grating to perform left and right diffraction of the same intensity. It creates the order. These symmetric diffraction orders constitute the SiSAM It is used to obtain the arm of an interferometer. Selective drying of beams of symmetric order A system with two or three mirrors is used to return the second diffraction wave to the grating that causes the system is used. However, this spectroscopic needle has all the drawbacks mentioned above.

Entrance holes, reference means and symmetrically drawn diffraction grating arranged sequentially downstream of the light beam an auxiliary mirror whose reflective surface is parallel to the grooves of the diffraction grating and perpendicular to the work surface. , a line where the plane of the working surface of the diffraction grating and the plane of the reflective surface of the auxiliary mirror intersect; installed on a common foundation located above and configured to rotate about an axis comprising two scanning mirrors, an exit aperture, and a recording device optically connected to the exit aperture. , one of the scanning mirrors reflects the beam from the diffraction grating, and the other scanning mirror reflects the beam from the diffraction grating. SISAMs configured to reflect the beam from an auxiliary mirror are also known. (See, for example, Canadian Patent No. 1034786, issued July 1978).

This spectrometer is characterized by its simple scanning means, small size, and light weight. has advantages. Additionally, this spectrometer is capable of using synchronous detection methods.

However, this spectrometer suffers from the drawback that amplitude and phase aberrations affect the measurement accuracy. have

This amplitude aberration is due to the lack of a zero band in the interference pattern, Makes the spectral reproduction from Resistorodalum unclear.

In this spectrometer, the instrument function of the registered signal during synchronous detection is Compatible with optical phase difference. This is the cause of the optical aberration mentioned above, and this spectral This makes the optical characteristics of the meter less stable. The phase aberration is caused by the diffraction grating and the auxiliary mirror. This is due to substantial variation in the relative position of the optical elements, primarily due to the Attachment is due to thermal expansion of the fixture. Such phase aberrations can be eliminated by auxiliary equipment. can only be overcome by strict stabilization (within 0.1 degrees) of the spectrometer temperature. Wear.

Disclosure of invention The present invention eliminates amplitude aberrations, resulting in a spectral A scanning mirror system that can reproduce clearly and a recording device that can eliminate phase aberration. It provides a spectrometer using interferometrically selective amplitude modulation (SISAM) with Ru.

These objectives include entrance holes, fiducials, arranged sequentially towards the downstream side of the light beam. means, the reflecting surface of the symmetrically drawn diffraction grating 1 is parallel to the f-line of the diffraction grating and An auxiliary mirror installed perpendicular to the working plane of the diffraction grating, Rotation around an axis that lies on the line of intersection between the plane of the optical surface and the plane of the reflective surface of the auxiliary mirror. two scanning mirrors, an exit hole, mounted on a common base configured to and a recording device optically connected to the exit hole, one of the two scanning mirrors. one mirror reflects the beam from said diffraction grating, and the other mirror reflects the beam from said auxiliary mirror. A spectrometer (SISAM) configured to reflect a beam and having parallel surfaces. the front plate configured to reflect the beam from said auxiliary mirror; installed between the scanning mirror and the base, the plate has a thickness h and has a formula Satisfying l≦h≦L, (However, l is the plane of the working surface of the diffraction grating and the auxiliary mirror whose end face faces the grating. L is the length of the diffraction grating in the direction perpendicular to the parallel ruled lines. It is. ) that the recording device has no means of compensating for the phase aberration of the spectrometer; This is achieved by a spectrometer with special features.

A device in which a photodetector, synchronous detector, and indicator are connected in series, and an output terminal and a generator connected to a second input of the synchronous detector. In order to compensate for phase aberration in a recording device, according to the present invention, the phase aberration compensation method is The stage comprises a second synchronous detector, a frequency doubler and a unit for vector addition of electrical signals. Eh, the second synchronous detector has one input end connected to the output end of the photodetector, and the other end connected to the output end of the photodetector. an output end is connected to the output end of the generator via the frequency doubler; The electrical signal vector addition unit is connected to the output terminals of the first and second synchronous detectors. It is desirable that it be inserted between the input terminal of the indicator and the input terminal of the indicator.

In order to simultaneously measure the refractive index dispersion and absorption spectrum of the material being investigated, The light meter is a transparent chamber fixed to one of said scanning mirrors with mutually parallel side walls. and the size of this chamber is equal to the size of the scanning mirror. Moreover, the recording device is a unit for calculating arctanUω/　U　Zω, and the calculation unit and an indicator connected to the output end of the. The unit has each synchronous detector It has two input terminals respectively connected to the output terminals of. However, here Uω is the U3O is the amplitude of the output signal of the first synchronous detector, and U3O is the amplitude of the output signal of the second synchronous detector. It is the width.

The spectrometer of the present invention using interference selective amplitude variation tW+ (SI SAM) The advantage is that very accurate measurements can be made because width aberrations are compensated for. this spectrometer has many uses in analytical spectroscopy for recording continuous spectra or lines of emission as well as absorption. Find applications. According to the invention, recording the second harmonics of an optically modulated signal makes it possible to utilize an auxiliary channel to the recording device for It becomes possible to fully utilize the radiation beam and eliminate phase aberrations. Besides, double channel The use of synchronous detection makes SISAM circuits similar to conventional spectrometer circuits. can be made into a value.

Brief description of the drawing The invention will be explained in more detail with reference to preferred embodiments and the accompanying drawings, in which: FIG.

Figure 1 shows the functional block diagram of a typical ray for a spectrometer using interferometrically selective amplitude modulation. Showing an eargram.

FIG. 3 has another functional block diagram showing phase aberration compensation according to the present invention. 2 shows another embodiment of a spectrometer featuring a recording device with means;

FIG. 4 shows an optical diagram of the spectrometer of FIG. 1 according to the invention.

FIG. 5 shows an optical diagram of the spectrometer of FIG. 3 according to the invention.

BEST MODE FOR CARRYING OUT THE INVENTION A spectrometer using interferometrically selective amplitude modulation (SISAM) according to the present invention (Fig. 1) ), the mounting is fixed by the part 4 and housed inside the case 2, i.e. It has a lens 3, the focal plane of which is located between the lens 3 and the entrance hole 1.

The mirror 5 is fixed by a portion 6 and is oriented at 45° with respect to the optical axis of the lens 3. Cents are measured in degrees. A flat surface characterized by symmetrical groove lines 8 forming a working surface. A planar diffraction grating is fixed on a base 9 inside the case 2. Auxiliary mirror 10 is secured immovably on the same base 9 and has plates 11 and 12. Forming a mink capacitor. The plate 11 reflects the reflection of this auxiliary mirror 10. It is also called a reflective surface.

The auxiliary mirror 10 has its reflective surface 11 aligned with the groove lines 8 of the diffraction grating 7. The lens 3 is arranged parallel to the working surface of the diffraction grating 7 and at 90 degrees to the working surface of the diffraction grating 7. The optical axis of is configured to pass through the center of the grating 7. Case 2 is the opposite. a first scanning mirror 1 whose incident surface is configured to reflect the light beam from the diffraction grating 7; 4, the reflective surface is configured to reflect the light beam from the auxiliary mirror 10; A base 13β common to the two scanning mirrors 15 is built-in. The parallel plate 16 It is installed between the scanning mirror 15 and the base 13. The support of the plate 16 The size is the same as the size of the mirror 15, and its thickness h is 2p≦h≦L I am satisfied. Here, l is the end face 18 of the auxiliary mirror 10 and the diffraction facing it. L is the gap existing between the grating 7 and the working surface, and L is the diffraction gap perpendicular to the direction of the groove lines 8. This is the length of the working surface of the grid 7.

Parallel plate 16 is mounted on base 13 by optical contact or the like.

The common base 13 is connected to the shirt I.2 by means of a screw pair, namely a screw 21 and a nut 22. It is secured on a base 19 configured to be centered at 0. This base 1 9 are fixed in successive positions by springs 23.

The shaft 20 around which the base 19 rotates is connected to the reflective surface 11 of the auxiliary mirror 10. A straight line that intersects the plane 25 where the plane 25 exists and the plane 17 where the working surface of the diffraction grating 7 exists It is installed on 24.

The exit hole 26 is provided in the case 2 at a position symmetrical to the entrance hole 1 with respect to the mirror 5. ing. The recording device 27 is provided with means for compensating for phase aberrations in the exit hole 26. It is installed at the back.

Both plates 11 and 12 of the capacitor of the auxiliary mirror 10 pass through the opening of the case. It is connected to the recording device 27 by an electric wire.

In this embodiment, the spectrometer is a recording device equipped with means for compensating for phase aberrations. It has a position 27. This recording device is shown in Figure 2 and was created in Moscow in 1983. The harmonic vibration generator described in “Semiconductor Circuit Technology” published by MIR Publishing Company generator 28 and a photodetector 29 connected in series (e.g. 1972 Moscow Published by Nauka Publishing House A. N. Zaidel G. V. 0strovsk y, Yu.

1.0s Trovsky co-author “Tekhnika i Praktika 5” pektroskopii'' (see description of the photomultiplier tube). a light-sensitive element placed behind the aperture 26 and placed in the focal plane of the lens 3; , for example, as described in ``Semiconductor Circuit Technology'' published by MIR Publishing House in Moscow in 1983. For example, two synchronous detectors 30 and 311 published by MIR Publishing House, Moscow in 1979. Frequency doubler 329 described in the row "Functional amplifiers and linear integrator circuits" e.g. 1 Described in ``Design and Production of Electronic Equipment'' published by MIR Publishing House in Moscow in 1980. A unit 33 for vector addition of electrical signals obtained. and indicator 3 of recorder etc. It features 4.

In the embodiment of the recording device 27 shown in FIG. 2 with phase aberration compensation means, Generator 28 connects capacitor plates 11 and 12 (of auxiliary mirror 10) and directly connected to the first input of the synchronization detector 30 and connected directly to the first input of the synchronization detector 32. is connected to via a frequency doubler 32. The output end of the photodetector 29 is for consent detection. The electrical signal vector addition unit 3 is connected to the second input terminal of the 3 is the first and second synchronization detector.Compared to the SISAM in FIG. An example of M is a transparent mirror with parallel side windows mounted on the scanning mirror 14. It has a small chamber 35. The size of the small chamber 35 is the same as that of the mirror 14. However, the original A light chamber 35 is placed above the scanning mirror 15.

The recording device 36 of SISAM in FIG. 3 is a It comprises an auxiliary unit 37 for calculating rctan Uω/UZω. child Here, U, , is the amplitude of the output signal of the synchronous hand odor detector 3o, and U3O is the amplitude of the output signal of the synchronous hand odor detector 3o. is the amplitude of the output of 1.

This auxiliary unit 37 has two inputs, one for each synchronous detector 30 and 31. Connected to the output end. The recording device 36 is further connected to the output end of the auxiliary unit 37. and an indicator 38.

The spectrometer shown in Figures 1 and 2, which utilizes Interferometrically Selected Amplitude Modulation (SISAM), is It works like this.

The incident light beam 39 (FIG. 4) to be investigated enters the hole 1 and passes through the semi-transparent mirror 5 and the lens. It passes through the diffraction grating 7 and is incident on the diffraction grating 7 at a right angle. It is diffracted into two beams 40 and 41 with constant waves.

The light beam 40 and the light beam 41 reflected from the reflective surface 11 of the auxiliary mirror 10 are: proceeding in parallel directions towards a common base 13; The parallel plate 16 is scanned The reflective surfaces of mirrors 14 and 15 are kept parallel, so that the spectrometer provides conditions for automatic reference of both beams 40 and 41 when adjusted.

The two diffracted light beams 40 and 41 are returned to the diffraction grating. Beam 40 is running It is reflected from the reflection surface of the inspection mirror 14. Beam 41 is the reflection surface 1 of auxiliary mirror IO 1. The light is sequentially reflected on the scanning mirror 150 reflection surface, and then again on the reflection surface of the mirror 10. Ru.

Upon return, both beams 40, 41 are diffracted in one direction in the form of an exit beam 42, and the lens 3, is reflected by the mirror 5, passes through the exit hole 26, and reaches the recording device 27. . In this spectrometer example, a semi-transparent mirror 5 separates the incoming and outgoing beams 39.43. It is used as a means of separation.

a parallel plate with a thickness h arranged between the scanning mirror 15 and the base 13; With 16 effects! According to the condition ≦h≦H, the wavelength of the beam 41 becomes shorter. As a result, the path at any point in the scanning range over the entire wavelength range depending on the appearance The interference pattern at the working surface of the diffraction grating 7 in the interference band corresponding to the zero difference of is obtained. Ru. Due to the effect of zero interference band, the speed analyzed on the basis of Registro-Durham is It can compensate for spectral aberrations and unclear reproduction. at a given wavelength The image of all points in the entrance hole 1 (Fig. 4) created by the beams 40 and 41 is Matches the outlet hole 26.

Each point of hole 1 does not coincide for other wavelengths. This means that interference at the exit hole 26 means selective at a given wavelength. Modulation in this spectrometer example The means is an auxiliary mirror 10. The voltage is supplied from the generator 28 (Fig. 2) to the auxiliary voltage. When supplied to the mirror 10, its reflective surface 11 performs a reciprocating motion. This reciprocating motion The path difference between beams 40 and 41 is varied periodically, so that the radiation of a given wavelength is The intensity of the output light beam 42 (FIG. 4) is changed. A beam of light 42 that approximates a given wavelength The line also passes through the exit hole 26, but its intensity is left unmodulated. Light from recording device 27 The light flux 42 investigated and recorded by the detector 29 is a function of the given wavelength of light. and a fixed component that is a function of light of other wavelengths passing through the exit hole 26. Contains. This fluctuation component separated and amplified by the recording device 27 is It is proportional only to the intensity of light at a given wavelength. This wavelength is the spectrum of light to be investigated. Serves as an indicator of ingredients.

The spectrum is scanned every time the base 19 is rotated around the shaft 20. and the sequential automatic reference positions of the reflective surfaces of both mirrors 14 and 15 are adjusted to the investigated wavelength. registered against.

In the spectrometer shown in Figure 4, amplitude aberrations are compensated, but additional phase aberrations are A difference is created and adds appropriately to the phase aberration mentioned above. This additional phase aberration is due to the thickness This is due to the presence of the parallel plane plate 16 having h. The plate 16 is A modulation phase corresponding to the wavelength λ of the interference beams 40 and 41 is generated according to the following equation.

2πh/λ−Φ(λ) The recording device 27 equipped with means for compensating for phase aberrations operates as follows.

The emitted light beam 42 is supplied to the photodetector 29 (FIG. 4) through the exit hole 26. Ru. The fluctuation component of the emitted light beam 42 is given by the following equation, where J and (λ) are the intensity of the incident light beam 39. is the amplitude component of the transmission function of the spectrometer, and Φ(λ) is the interference beam 40 and 41, and includes a complete Fourier harmonic spectrum.

Due to the discoloration modulation in the optical system in question, Φ(λ) is %formula%() given by.

Here, a is the modulation amplitude, ω is the modulation frequency, t is time, %Po is modulation amplitude, +'(λ) is the phase component that is a function of wavelength.

The following equation is derived.

Instep. +'F　(λ)−Φ. (λ) When expanded into a Fourier series, the first harmonic amplitude is given by the following equation.

■ω(λ)=ro(λ)W(λ)・5inCΦ. (λ)) -2FB, (a) Here, Fill is a Bessel function of the first kind.

The second harmonic amplitude is given by the following equation.

I2ω(λ)+IO(λ)W(λ)・cos[Φ. (λ))’ 2 Fax ( al Here, FB2 is a Bessel function of the second kind.

The first synchronization detector 30 connects the output end of the generator 28 to the second input end of the light receiver 29. from the exit beam 42 recorded by the receiver 29 by means of a reference signal supplied to the , separates the first harmonic vibration. The second synchronization detector 31 is connected via a frequency doubler 32. The reference signal supplied from the output end of the generator 28 to the second input end of the light receiver 29 Thus, the second harmonic oscillation is separated from the luminous flux 42 recorded by the photoreceiver 29.

The output signals of both synchronization detectors 30 and 31 are sent to the electric signal vector addition unit 33. The signal is supplied to two input terminals and further reaches an indicator 34.

In the example of the recording device W27 described above, the electric signal vector addition unit 33 The signal supplied to the input terminal of can be expressed as follows.

From the output end of the first synchronization detector 30 to Uω=, Tω(λ) second synchronization! t11 detector From the output end of 31, U2ω=Kt1tω(λ) where + is the first synchronous detection The amplification coefficient of the output device 30, K2, is the amplification coefficient of the second synchronous detector 31.

The condition K+Fa+(a)=KzFgz(a) is satisfied, and this is the case for each amplification coefficient. 1 and 2 or indicator 3 if achieved by proper selection of amplitude. All phase aberrations of the signal fed to the input of 4 are fully compensated. because Well, the initial phase difference! . The signal depends on the phase component type (λ) which is a function of wavelength and The extent to which it is present disappears completely.

The obtained signal contains only information that depends on the amplitude component of the exit beam 42.

Other examples of spectrometers shown in FIG. 3 operate as described above, but include the following: It is unique in this respect.

The two diffracted beams 40, 41 (FIG. 5) return to the diffraction grating 7. scanning mirror 1 The light beam 40 reflected by the reflective surface 4 is directed to a transparent flat surface containing the material to be studied. It passes through the row-side small chamber 35 twice. Reflective surface 11 of auxiliary mirror 10. scanning mirror 15 reflective surface.

Then, the light beam 41 that is sequentially reflected again from the reflecting surface of the auxiliary mirror 10 also enters the small chamber. Pass 35 twice.

When the small chamber 35 is filled with the substance to be studied, the amplitude of the emitted light beam 42 is , varies by an amount that is a function of the amplitude absorption coefficient α(λ), while the phase component φ(λ) It has an increment that is a function of the refractive index n(λ) of this material.

The emitted light beam 4 reaches the light receiver 29 (FIG. 3) of the recording device 36 through the exit hole 36. 2 has a fluctuation component given by the following equation.

■,,(λ)=to(λ)　e−′m　H(λ)・cos(Φ(λ)　−2rc (n-1)m/λ) Here, m is the thickness of the absorption layer of the substance to be investigated.

The influence of the small chamber 35 on the amplitude component can be ignored, and the influence of the phase component is contained within φ(λ).

In this case, the continuous spectral source is io(λ) = 1° = constant is used.

The signal taken out from the output end of the quantity synchronization detector 30.31 is a vector of electrical signals. are supplied to two inputs of the adding unit 33 and further supplied to the indicator 34. , to the two input ends of the unit 37 that simultaneously calculates arctan Uω/U2ω. The signal is supplied to the indicator 38. The signal of indicator 34 has an amplitude It only contains information about the absorption coefficient α(λ), while the signal of indicator 38 is Contains information regarding the refractive index n(λ) of the material to be studied. Continued Registro Durham The processing gives a spectral distribution of the quantities n(λ) and α(λ), resulting in The extinction coefficient of the research target substance and (λ) − αλ/4π are given, and these are recorded simultaneously. be done.

Industrial applicability This spectrometer, which uses interferometrically selective amplitude modulation (SISAM), is useful for environmental protection and astrophysics. for the purpose of geology, metallurgy, pure metal 1 alloys, semiconductor production. It is mainly intended for the analysis of trace impurities in multi-component systems.

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Claims (1)

[Claims] 1. entrance holes (1), collimation means, arranged sequentially towards the downstream side of the light beam; A diffraction grating (7) having symmetrically drawn ruled lines (8), a reflecting surface (11) parallel to the ruled lines (8) of the diffraction grating (7) and perpendicular to the working surface of the diffraction grating The installed auxiliary mirror (10), the plane (17) of the working surface of the diffraction grating (7) and A pattern on the line of intersection of the reflective surface (11) of the auxiliary mirror (10) with the plane (25) installed on a common base (13) configured to rotate about a shaft (20); The two scanning mirrors (14, 15) located, the exit hole (26), and the exit hole (2 6) with a recording device (27) optically connected to one of the two scanning mirrors; One mirror reflects the light beam from the diffraction grating (7), and the other mirror reflects the rays from the auxiliary mirror (7). 10) spectroscopy using interferometrically selective amplitude modulation configured to reflect light rays from wherein the parallel plate (16) reflects the light beam from the auxiliary mirror (10). between the scanning mirror (15) and the base (13) configured to installed, the plate (16) has a thickness h and satisfies the formula l≦h≦L, and the plate (16) has a thickness h and satisfies the formula l≦h≦L; The recording device (27) is characterized in that it comprises means for compensating for phase aberrations of the spectrometer. spectrometer. However, l is the plane (17) of the working surface of the diffraction grating (7) and the end face (18) of the grating. (7) is the gap between the auxiliary mirror facing the auxiliary mirror, and L is the gap perpendicular to the ruled line. is the length of the grating in the normal direction. 2. The recording device (27) includes a light receiver (29), a synchronization detector (30), and an indicator. a series-connected array of synchronous detectors (34) and an output terminal of the synchronous detector (30); and a generator (30) connected to the two input terminals. The spectrometer as described above, wherein said means for compensating for phase aberration of the spectrometer comprises a second spectrometer. frequency detector (31), frequency doubler (32), and electric signal vector addition unit. The second synchronous detector (31) has one input end connected to a light receiver (29). ), and the other output terminal passes through the frequency doubler (32) and connects to the output terminal of the frequency doubler (32). connected to the output end of the generator (28), and also connected to the electrical signal vector addition unit (33) represents the output terminals of the first and second synchronization detectors (30, 31) and the input terminals of the first and second synchronization detectors (30, 31). The device according to claim 1 is inserted between the indicators (34). Spectrometer. 3. The spectrometer has a transparent chamber (3 5), said chamber being fixed to one of said scanning mirrors (14), said chamber (35) ) is equal to the size of the scanning mirror (14), and the size of the recording device (36) is equal to that of the scanning mirror (14). ) includes a unit (37) for calculating arctanUω/U2ω and the calculation unit. an indicator (38) connected to the output end of the unit (37); The kit has two input terminals, each connected to the output terminal of each synchronous detector (30, 31). 3. A spectrometer according to claim 2, characterized in that the spectrometer is connected to However, here Uω is the amplitude of the output signal of the first synchronization detector (30), and U2ω is It is the amplitude of the output signal of the second synchronous detector.