CN100443869C - High stability and high spectral resolution interference imaging spectrometer imaging method and spectrometer - Google Patents

Abstract

An imaging method of interference imaging spectrometer with high stability and high spectral resolution and a spectrometer for realizing the method are disclosed, which convert the target light into parallel beams, and divide the parallel beams into reflected beams and transmitted beams through a beam splitter. The reflected beam is reflected by the turning mirror and the corner reflector and then returns to the beam splitter, and is converged by the Fourier lens to form a first optical path. The transmitted light beam returns to the beam splitter after being reflected by the corner reflector and the plane reflector, and is converged by the Fourier lens to form a second light optical path, and an optical path difference is generated when the two light beams reach the detector. The corner reflector moves synchronously along a plane vertical to the beam splitter, the optical path difference range of the two beams of light changes, and after interference spectrograms corresponding to different optical path difference ranges are superposed, a target restoration image with high spectral resolution is obtained through Fourier transformation. The invention solves the technical problems that the background technology can only sample single pixel, or the system has complex structure and poor stability, etc., has good real-time performance and is particularly suitable for large-area scanning of large targets.

Description

High stability and high spectral resolution interference imaging spectrometer imaging method and spectrometer

technical field

The invention relates to a moving-mirror interference imaging method for quickly obtaining target interference spectrum and a spectrometer for realizing the method, in particular to an imaging method for an interference imaging spectrometer with high stability and high spectral resolution and a spectrometer for realizing the method.

Background technique

The earlier imaging spectrometer is the Michelson interferometric time-modulated space imaging Fourier transform spectrometer [D Simenoni. New concept for high-compact imaging Fourier transform spectrometer (IFTS)[ C]. SPIE, 1991, 1479: 127-138.], the Michelson interferometric time-modulated spatial imaging Fourier transform spectrometer developed by the Lawrence Livermore Laboratory in the United States in 1995 [Michael R Carter, Charles LBennctt , DavidJ Fields, et al. Live more imaging Fourier transform spectrometer[C]. SPIE, 1995, 2480: 380-386.]. It adopts a linear reciprocating scanning method, and must turn at the end of each scanning, and collect data after stabilization. Therefore, a reference laser must be used to provide a corresponding coherent sample spectrum when collecting data. The scanning speed is controlled by the servo system, and reverse scanning is provided when turning. As the scanning frequency and speed increase, the round-trip time becomes an important part of the total scanning time. In order to obtain an accurate sampled interferogram, the bandwidth required by the servo system increases dramatically. As the scanning speed increases, the resolution will be restricted by the above factors. Since the round trip time becomes an important part of the total scan time, the duty cycle will be reduced due to the constraints of servo system power, scan device size, scan device weight, and system settling time. For example, it is extremely difficult to achieve reciprocating scanning at a scanning frequency of 360 scans per second and a single scanning time of 2.8 milliseconds. A return and settling time of 1-2 milliseconds reduces the duty cycle to 33-50%. In the case of a high repetition rate, the scan length which affects the resolution will be constrained. Therefore, the Michelson interferometric time-modulated spatial imaging Fourier transform spectrometer has poor stability and complicated process, and is only suitable for objects with slow spatial and spectral time changes.

Rotating mirror interferometer imaging is a deformed time-modulated Michelson interferometry [J.Peter Dybward, et.al. "New Interferometer Design Concept", STC Technical Report 2637, Science and Technology Corp, Hampton, VA, under contract #DAAA15-89-D-007, US Army CRDEC, APG, MD, 8/92.], the technology has an empty sweep during the scan. That is, when the rotating mirror rotates, the interference spectrum can only be obtained within a certain angle, and it is empty scan at other angles. The work efficiency is low, and it can only sample a single pixel, that is, it can only scan a point target, and can only be applied to the scanning of an angle of light.

A kind of ultra-high-speed scanning Fourier transforminfared spectrometry (Peter R.Griffiths, Blayne L.Hirsche, Christopher J.Manning.Ultra-rapid-scanningFourier transforminfared spectrometry.Vibrational Spectroscopy19(1999)165-176.), although solved The problem of mirror empty scanning, but still can only sample a single pixel. If you want to obtain the interferogram of a line target or a surface target, you must attach a pre-scanning system to the front of the system to scan each point of the target one by one, and finally gather to obtain the interferogram of the entire target. The existing defect is that the system structure is complex, the volume is large, and the weight is heavy. Due to the poor real-time performance, not only the quality of the spectrogram is affected, but also the scanning time is long, the scanning speed is low, the resolution is low, and the applicable working range is also narrow.

Contents of the invention

The object of the present invention is to provide an imaging method of an interference imaging spectrometer with high stability and high spectral resolution and a spectrometer for realizing the method, which solves the problems of single-pixel sampling, low work efficiency, or system structure in the background technology. Complexity, low scanning speed, poor stability, and relatively low spectral resolution technical problems.

Technical solution of the present invention is:

An imaging method for an interference imaging spectrometer with high stability and high spectral resolution, which is special in that the method includes the following steps

1) The collimating lens 1 converts the beam from the target into a parallel beam;

2) The beam splitter 2 divides the parallel light beam into reflected light beam I _F and transmitted light beam _IT ;

(i) The reflected light beam I _F split by the beam splitter 2 is reflected multiple times by the rotating mirror 3 and the A-angle reflector 5, then returns to the beam splitter 2, and converges to the detector 9 through the Fourier lens 8 to form the first The optical path of the beam of light;

(ii) the transmitted light beam I _T that is split by the beam splitter 2 arrives at the plane reflector 7, is repeatedly reflected by the plane reflector 7 and the B-angle reflector 6, then returns to the beam splitter 2, and is converged by the Fourier lens 8 to Detector 9, forming the optical path of the second beam of light;

3) When the first beam of light and the second beam of light pass through the Fourier lens 8 and reach the detector 9, an optical path difference is generated to become two beams of coherent light, and an interference spectrum is generated on the detector 9;

4) synchronously move the A corner reflector 5 and the B corner reflector 6 along the direction perpendicular to the plane of the beam splitter 2, and change the optical path difference range of the first beam and the second beam of light passing through the Fourier lens 8 to the detector 9, Generate an interference spectrogram corresponding to the changing optical path difference range on the detector 9;

5) After the interferometric spectra corresponding to different optical path difference ranges are superimposed, Fourier transform is performed by the computer processing system 12 to obtain a target restoration image with high spectral resolution.

The optical path of the above-mentioned first beam of light can be

1) The reflected light beam I _F split by the beam splitter 2

(i) is reflected to the A angle reflector 5 by the rotating mirror 3, and the A angle reflector 5 reflects the incident light along the direction parallel to the incident direction to the rotating mirror 3;

(ii) the rotating mirror 3 reflects the light back to the beam splitter 2;

(iii) The light reflected back to the beam splitter 2 is further divided into a reflected beam I _FF and a transmitted beam I _FT ;

2) The transmitted light beam I _FT passes through the beam splitter (2), and converges to the detector (9) through the Fourier lens (8);

The optical path of the above-mentioned second beam of light can be

1) The transmitted light beam _IT split by the beam splitter 2

(i) is reflected to the B angle reflector 6 by the plane reflector 7, and the B angle reflector 6 reflects the incident light back to the plane reflector 7 along a direction parallel to the incident direction;

(ii) Flat mirror 7 reflects light back to beam splitter 2:

(iii) The light reflected back to the beam splitter 2 is further divided into a reflected beam I _TF and a transmitted beam I _TT :

2) The reflected light beam I _TF converges to the detector (9) through the Fourier lens (8).

A spectrometer for realizing the imaging method of the above-mentioned high-stability and high-spectral-resolution interference imaging spectrometer, comprising a Fourier lens 8, a detector 9 located on the focal plane of the Fourier lens 8, and a computer processing system 12 connected to the detector 9, arranged on The collimator lens 1 on the main optical axis of the front optical system 11, the beam splitter 2 arranged on the axis 00' of the collimator lens 1, its special feature is that it also includes a plane reflector 7, which is connected with the motor 4 The rotating mirror 3 is connected with the driving mechanism 10 and can move synchronously along the A angle reflector 5 and the B angle reflector 6 in the direction perpendicular to the plane of the beam splitter 2; the position of the plane reflecting mirror 7 should satisfy: 3. When the A corner reflector 5 and the B corner reflector 6 are positioned at a certain position,

1) the light on the main optical axis is the first beam light by the reflected light beam I _F that the beam splitter 2 splits for the first time; The beam splitter 2, the optical path of the first beam of light formed by the Fourier lens 8 and converged to the detector 9:

2) the light on the main optical axis is the second beam of light by the transmitted light beam _IT that the beam splitter 2 splits for the first time; the second beam of light arrives at the plane mirror 7, through the plane mirror 7 and the B angle reflector 6 Multiple reflections, return to the beam splitter 2, and converge to the optical path of the second beam of light formed by the detector 9 through the Fourier lens 8;

3) The intersection point where the first beam returns to the beam splitter 2 coincides with the intersection point where the second beam returns to the beam splitter 2:

4) the optical path of the transmitted light beam I _FT split by the beam splitter 2 again for the first beam of light overlaps with the second reflected light beam I _TF split by the beam splitter 2 again;

5) The optical path of the first beam of light is equal to the optical path of the second beam of light; the position of the beam splitter 2 should also meet:

1) Can receive the initial incident light passing through the collimating lens 1;

2) Can receive the reflected light reflected back by the rotating mirror 3 and the A angle reflector 5;

3) Can receive the reflected light reflected back by the plane reflector 7 and the B angle reflector 6; the structure of the A angle reflector 5 and the B angle reflector 6 is the same, and the two are connected back to one another: the Fourier The optical axis of the lens 8 is located on the optical path where the transmitted light beam I _FT of the first light beam coincides with the reflected light beam I _TF of the second light beam.

The above-mentioned detector 9 is preferably an infrared detector, specifically a CCD infrared detector can be used.

It is advisable for the above-mentioned rotating mirror 3 to be formed by an oblique end face of a cylinder, which is convenient for processing and installation.

The present invention has the following advantages:

1. High-frequency scanning can be realized, and the stability is good. With the rotating mirror moving mirror, the system runs continuously. When the scanning speed is high, the rotation servo system can still maintain good stability due to the inertia.

2. Strong anti-interference ability. Due to the extremely short time to obtain the interferogram, the system is less sensitive to vibration, and the frequency of mechanical vibration generally has no effect on the quality of the spectrogram.

3. The optical path formed by the matching of the corner reflector and the rotating mirror has self-compensation characteristics, so that the present invention has better anti-interference performance.

4. High scanning efficiency. The rotating mirror uses the end surface of a cylinder with a certain inclination as the reflecting surface, and it rotates under the drive of the motor, so there is no idle scanning phenomenon and the scanning efficiency is high.

5. It can realize direct scanning of line target or surface target. The use of corner reflectors can not only scan the light of the main optical axis, but also scan the light with a certain angle, which can directly scan the line target or surface target, shorten the scanning time, and further improve the scanning efficiency and the quality of the spectrogram.

6. Good real-time performance, higher resolution and wide working range. Especially suitable for large area scanning of larger objects.

7. Low power consumption and low driving power required.

8. Simple structure, small size and light weight.

9. The two corner reflectors with the same structure are fixed back to one body, and the structure is symmetrical, which can offset the influence of processing errors, and the position is easy to determine during assembly.

10. The A corner reflector 5 and the B corner reflector 6 are bound together as a whole, and when they move together in the horizontal direction, the influence of the horizontal displacement on the two will cancel each other out, which has the characteristic of self-compensation and improves the signal-to-noise ratio.

11. The combination design of the B-angle reflector 6 and the plane reflector 7 greatly reduces the overall structure of the instrument and reduces the weight of the instrument.

12. The spectral resolution is greatly improved. The corner A reflector 5 and the corner B reflector 6 move horizontally at the same time driven by the driving mechanism 10 to obtain interference spectrum diagrams in different optical path difference ranges, and these interference spectrum diagrams are superimposed in the form of cube data.

Through computer processing, the spectral resolution can be several times or even higher than when the positions of the A-angle reflector 5 and B-angle reflector 6 are fixed.

Description of drawings

Fig. 1 is the structural principle schematic diagram of the present invention;

Fig. 2 is a schematic structural diagram of an embodiment of the present invention.

Description of reference numerals: 1-collimating lens, 2-beam splitter, 3-turning mirror, 4-motor, 5-A corner reflector, 6-B corner reflector, 7-plane reflector, 8-Fourier lens , 9-detector, 10-driving mechanism, 11-front optical system, 12-computer processing system, 13-observed object.

Detailed ways

Referring to Fig. 1, the optical system of the present invention is mainly made of collimating lens 1, beam splitter 2, rotating mirror 3, A angle reflector 5 and B angle reflector 6, front optical system 11 and Fourier lens 8; Interference system It is mainly composed of a collimating lens 1, a beam splitter 2, a rotating mirror 3, an A-angle reflector 5 and a B-angle reflector 6, a plane mirror 7 and a Fourier lens 8. The detection system is mainly composed of a detector 9, and the information processing system is mainly composed of a computer processing system 12, see Figure 2.

Working principle of the present invention:

1) When the rotating mirror 3 is stationary, the beam on the main optical axis is split into two beams by the beam splitter 2, and the optical paths of the two beams are equal.

2) When the rotating mirror 3 rotates under the drive of the motor 4, the reflected light beam I _F split by the beam splitter 2 for the first time returns to the beam splitting after being reflected by the rotating mirror 3 and the A-angle reflector 5 for many times 2, the optical path of the first beam of light reaching the Fourier lens 8 will change. The transmitted light beam I _T split by the beam splitter 2 for the first time returns to the beam splitter 2 after being reflected by the plane reflector 7 and the B-angle reflector 6 multiple times, and is reflected by the beam splitter 2 to reach the Fourier lens 8 The optical path of the second beam of light does not change. The optical paths of the two beams of light no longer overlap, and the optical paths finally reaching the detector 9 are no longer equal, thereby generating an optical path difference, becoming two beams of coherent light, and producing an interference pattern on the detector 9 . As the rotating mirror 3 rotates, the optical path difference between the two beams of light changes continuously, thereby obtaining an interference spectrum within a certain range of optical path difference.

3) While the rotating mirror 3 is rotating under the drive of the motor 4, the A-angle reflector 5 and the B-angle reflector 6 are driven by the driving mechanism 10 to move synchronously along the direction perpendicular to the plane of the beam splitter 2, so that the first beam of light The optical path difference range of the second beam of light passing through the Fourier lens 8 and reaching the detector 9 changes, and the interference spectrograms in different optical path difference ranges are generated on the detector 9 . The interference spectra corresponding to different optical path difference ranges are superimposed in the form of cube data, and after Fourier transformation by the computer processing system 12, it can be several times or even higher than when the positions of the A-angle reflector 5 and B-angle reflector 6 are fixed. Target restoration images with high spectral resolution.

For example: when corner A reflector 5 and corner B reflector 6 are at a certain position, the optical path difference range is [0, 1]; when corner A reflector 5 and corner B reflector 6 move to the next position, the optical path difference The difference range becomes [1, 2; A corner reflector 5 and B corner reflector 6 continue to move, and the range of optical path difference becomes [2, 3] at the next position... and so on, and changes are generated on the detector 9 The interference spectrum corresponding to the optical path difference range. After the interferometric spectra corresponding to these different optical path difference ranges are superimposed, Fourier transform is performed by the computer processing system 12 to obtain the restored target image.

4) The rotating mirror 3 rotates at a high speed driven by the motor 4 to realize high-speed scanning.

Referring to FIG. 1 , the axis 00 ′ of the collimator lens 1 of the present invention is located on the main optical axis of the front optical system 11 . The position of the beam splitter 2 should ensure that it can not only receive the initial incident light passing through the collimator lens 1, but also receive multiple reflections from the rotating mirror 3 and the A corner reflector 5, the plane mirror 7 and the B corner reflector 6 Back to the light. The position of the rotating mirror 3 connected with the motor 4 is set according to actual design needs. The A corner reflector 5 and the B corner reflector 6 have the same structure, and they are fixedly connected with their backs as a whole, connected with the driving mechanism 10, and can move synchronously along the direction perpendicular to the plane of the beam splitter 2 . The position of the plane reflector 7 should satisfy: when the rotating mirror 3, the A corner reflector 5 and the B corner reflector 6 are positioned at a certain position,

1) The reflected light beam I _F that the light on the main optical axis is separated on the beam splitter 2 for the first time is the first beam of light; The beam splitter 2 is divided into a reflected light beam I _FF and a transmitted light beam I _Fr by the beam splitter 2, and the light path of the transmitted light beam I _FT passing through the Fourier lens 8 to the detector 9 forms the light path of the first light beam.

2) the light on the main optical axis is split the transmitted light beam _IT for the first time on the beam splitter 2 as the second beam of light; it is repeatedly reflected by the plane mirror 7 and the B angle reflector 6, and then returns The beam splitter 2 is divided into a reflected light beam I _TF and a transmitted light beam I _TT by the beam splitter 2 , and the light path of the reflected light beam I _TF passing through the Fourier lens 8 to the detector 9 forms the light path of the second light beam.

3) The intersection point where the first light beam returns to the beam splitter 2 coincides with the intersection point where the second beam light returns to the beam splitter 2 again.

4) The optical paths of the first transmitted light beam I _FT split by the beam splitter 2 and the second reflected light beam I _TF split by the beam splitter 2 overlap.

5) The optical distance of the first beam of light is equal to the optical distance of the second beam of light. The optical axis of the Fourier lens 8 is located on the optical path where the transmitted light beam I _FT of the first light beam coincides with the reflected light beam I _TF of the second light beam. The detector 9 is located on the focal plane of the Fourier lens 8 . The detector 9 is preferably an infrared CCD detector. The observed object 13 shown in FIG. 2 is a rocket, which is a schematic diagram of the present invention for observing rocket exhaust.

The light transmission process of the present invention:

1. The light beam from the target reaches the collimating lens 1 through the front optical system 11, and the collimating lens 1 converts the target light beam into a parallel beam;

2. The beam splitter 2 splits the beam into a reflected beam _IF and a transmitted beam _IT . in,

1) The reflected light beam I _F split by the beam splitter 2

(1) reflect to the A corner reflector 5 through the turning mirror 3, and the A corner reflector 5 reflects the incident light along the direction parallel to the incident direction to the turning mirror 3;

(2) The rotating mirror 3 reflects the light back to the beam splitter 2;

(3) The light reflected back to the beam splitter 2 is divided again into a reflected light beam I _FF and a transmitted light beam I _FT . 2) The transmitted light beam _IT split by the beam splitter 2

(1) is reflected to the B angle reflector 6 by the plane reflector 7, and the B angle reflector 6 reflects the incident light back to the plane reflector 7 along the direction parallel with the incident direction;

(2) Plane reflector 7 reflects light back to beam splitter 2;

(3) The light reflected back to the beam splitter 2 is divided again into a reflected light beam I _TF and a transmitted light beam I _TT .

3. The reflected light beam I _F split by the beam splitter 2, the transmitted light beam I _FT split by the beam splitter 2 again, passes through the beam splitter 2 and reaches the Fourier lens 8, and is detected by the detector located on the focal plane of the Fourier lens 8 9 received.

4. The transmitted beam I _T split by the beam splitter 2 and the reflected beam I _TF split by the beam splitter 2 again pass through the Fourier lens 8 and are received by the detector 9 located on the focal plane of the Fourier lens 8 .

5. The reflected light beam I _F split by the beam splitter 2 for the first time is reflected by the rotating mirror 3 and the first A-angle reflector 5, then returns to the beam splitter 2, and converges to the detection through the Fourier lens 8; the beam splitter 2 The transmitted light beam I _T split for the first time reaches the plane reflector 7, is reflected by the plane reflector 7 and the B-angle reflector 6, returns to the beam splitter 2, and converges to the detector 9 through the Fourier lens 8 to form The optical path of the second beam of light; the two beams of light produce an optical path difference, become two beams of coherent light, and generate an interference spectrum on the detector 9 .

6. The A corner reflector 5 and the B corner reflector 6 move synchronously along the direction perpendicular to the plane of the beam splitter 2 under the drive of the driving mechanism 10, and the first and second beams of light pass through the Fourier lens 8 to reach the detector 9 optical path difference range, the interference spectrum of the first beam and the second beam in different optical path difference ranges can be obtained.

7. After superimposing the interference spectrograms corresponding to different optical path difference ranges, Fourier transform is performed by the computer processing system 12 to obtain a target restoration image with high spectral resolution.

Claims (5)

1. An imaging method of a high-stability high-spectral-resolution interference imaging spectrometer, characterized in that: the method comprises the following steps 1) The collimating lens (1) converts the beam from the target into a parallel beam; 2) The beam splitter (2) divides the parallel light beam into reflected light beam I _F and transmitted light beam _IT ; ①. The reflected light beam I _F split by the beam splitter (2) is reflected multiple times by the rotating mirror (3) and the A-angle reflector (5), then returns to the beam splitter (2), and passes through the Fourier lens (8) Converge to the detector (9) to form the optical path of the first beam of light: ②. the transmitted light beam I _T that is split by the beam splitter (2) arrives at the plane reflector (7), is repeatedly reflected through the plane reflector (7) and the B angle reflector (6), and then returns to the beam splitter ( 2), converging to the detector (9) through the Fourier lens (8) to form the optical path of the second beam of light; 3) When the first beam of light and the second beam of light pass through the Fourier lens (8) and reach the detector (9), an optical path difference is generated, becoming two beams of coherent light, and an interference spectrum is generated on the detector (9); 4) The interference spectrogram is subjected to Fourier transform by the computer processing system (12) to obtain the restored target image. 2. the imaging method of the high stability high spectral resolution interference imaging spectrometer according to claim 1, characterized in that: the optical path of the first beam of light is 1) The reflected light beam I _F split by the beam splitter (2) (i) is reflected to the A angle reflector (5) by the rotating mirror (3), and the A angle reflector (5) reflects the rotating mirror (3) to the incident light along the direction parallel with the incident direction; (ii) the rotating mirror (3) reflects the light back to the beam splitter (2); (iii) the light reflected back to the beam splitter (2) is split into a reflected beam I _FF and a transmitted beam I _FT ; 2) The transmitted light beam I _FT passes through the beam splitter (2), and converges to the detector (9) through the Fourier lens (8); The optical path of the second beam of light is 1) The transmitted light beam _IT split by the beam splitter (2) (i) is reflected to the B angle reflector (6) by the plane reflector (7), and the B angle reflector (6) reflects the incident light back to the plane reflector (7) along the direction parallel to the incident direction; (ii) a flat mirror (7) reflects the light back to the beam splitter (2); (iii) the light reflected back to the beam splitter (2) is split into a reflected beam I _TF and a transmitted beam I _TT ; 2) The reflected light beam I _TF converges to the detector (9) through the Fourier lens (8). 3. a kind of spectrometer that realizes the described high stability high spectral resolution interference imaging spectrometer imaging method of claim 1, comprises Fourier lens (8), is positioned at the detector (9) on the focal plane of Fourier lens (8), The computer processing system (12) that is connected with the detector (9), the collimator lens (1) that is arranged on the main optical axis of the front optical system (11), the collimator lens (1) that is arranged on the axis 00' of the collimator lens (1) The beam splitter (2) is characterized in that: it also includes an A-angle reflector (5) and a B-angle reflector (6), a plane mirror (7), and a rotating mirror (3) connected to the motor (4); The position of the plane reflector (7) should meet: when the rotating mirror (3), the A angle reflector (5) and the B angle reflector (6) are positioned at a certain position, 1) the light on the principal optical axis is the first beam light by the first beam splitter (2) the reflected light beam _IF that splits out for the first time; Second reflection, get back to the beam splitter (2) again, converge to the optical path of the first beam of light formed by the detector (9) by the Fourier lens (8); 2) the light on the main optical axis is the second beam _IT that the light on the main optical axis is separated by the beam splitter (2) for the first time; Reflect repeatedly with the B angle reflector (6), get back to the beam splitter (2), and converge to the optical path of the second beam of light formed by the detector (9) by the Fourier lens (8); 3) The intersection point where the first beam of light returns to the beam splitter (2) coincides with the intersection point at which the second beam of light returns to the beam splitter (2); 4) the first beam splitter (2) splits the transmitted light beam I _FT and the second beam splits the beam splitter (2) and the second beam splits the reflected light beam I _TF again; 5) The optical path of the first beam of light is equal to the optical path of the second beam of light; The position of the beam splitter (2) should also meet: 1) Can receive the initial incident light passing through the collimating lens (1); 2) Can receive the reflected light reflected back by the rotating mirror (3) and the A-angle reflector (5); 3) Can receive the reflected light that plane reflector (7) and B angle reflector (6) reflect back; The structure of described A angle reflector (5), B angle reflector (6) is identical, both backs solidified into one The optical axis of the Fourier lens (8) is located on the optical path where the transmitted light beam I _FT of the first light beam coincides with the reflected light beam I _TF of the second light beam. 4. The high stability and high spectral resolution interference imaging spectrometer according to claim 3, characterized in that: the detector (9) is an infrared detector. 5. The high-stability interference imaging spectrometer according to claim 3 or 4, characterized in that: the rotating mirror (3) is formed by an oblique end face of a cylinder.

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