CN111562002A - High-throughput, high-resolution, high-contrast polarization interference spectroscopy imaging device and method - Google Patents

Abstract

The invention relates to a high-throughput, high-resolution, high-contrast polarization interference spectrum imaging device and method. Overcome the problems of low detection accuracy of traditional Michelson interferometer imaging spectrometers and low energy utilization and resolution of traditional Sagnac interferometer-based imaging spectrometers, including collimating mirrors, polarizers, interferometers, and chromatic dispersion that are sequentially arranged in the optical path System, imaging mirror and detector; the interferometer includes a half-wave plate and an optical path difference etalon located in the outgoing optical path of the polarization beam splitter; the target light source is incident on the interferometer and the half-wave plate is used to adjust the vibration of S light or P light direction, so that the S light and the P light have the same vibration direction; use the optical path difference etalon to adjust the optical path of the S light and/or the P light, so that a fixed optical path difference is generated between the S light and the P light; non-polarized separation The beamer reflects and transmits both the S light and the P light with the same vibration direction and a fixed optical path difference to form interference fringes; the interference fringes are imaged on the detector after being dispersed by the dispersion system.

Description

High-throughput, high-resolution, high-contrast polarization interference spectroscopy imaging device and method

technical field

The invention belongs to the field of spectral imaging, and relates to a high-throughput, high-resolution, high-contrast polarization interference spectral imaging device and method.

Background technique

Interferometric imaging spectroscopy is a non-destructive, fast and sensitive target recognition and detection technology developed in recent years. At present, the technology is used in environmental monitoring, marine water quality monitoring, biomedicine, astronomical detection, optical fiber communication, military science and agriculture. It has important applications in many fields.

Interference spectrometers can generally be divided into two types: time modulation type and spatial modulation type. Imaging spectrometers based on Michelson interference and imaging spectrometers based on Sagnac interferometers are typical representatives of temporal modulation and spatial modulation, respectively. The former can achieve high-precision spectral measurement, but it is very sensitive to the disturbance of the external environment and the mechanical scanning accuracy during the spectral measurement process. The latter can automatically compensate for external disturbances and vibrations due to the design of the common optical path, and the absence of moving parts can make the system more stable, but this type of spectrometer still has problems of low energy utilization and resolution. Energy utilization is very important for weak light detection, especially in the astronomical field. With the development of interferometric imaging spectroscopy, the requirements for spectral resolution in the detection process are getting higher and higher.

SUMMARY OF THE INVENTION

In order to overcome the problems of low detection accuracy of the traditional Michelson interferometer imaging spectrometer and low energy utilization and resolution of the traditional Sagnac interferometer-based imaging spectrometer, the present invention proposes a high-throughput, high-resolution, high-contrast polarization interferometer. A spectral imaging device and method, the device combines a Sagnac interferometer, a polarizing element and a grating to improve the energy utilization rate, resolution and contrast of the spectrometer.

The technical solution of the present invention is to provide a high-throughput, high-resolution, high-contrast polarization interference spectroscopy imaging device, which is special in that it includes a collimator, a polarizer, an interferometer, and a dispersion system sequentially arranged in the optical path. , imaging mirrors and detectors;

The interferometer is a Sagnac interferometer with an asymmetric structure and a common optical path, which includes a polarization beam splitter, three plane mirrors and a non-polarization beam splitter arranged in sequence along the optical path; The half-wave plate and the optical path difference etalon in the propagation optical path of the non-polarizing beam splitter; the half-wave plate is located in any outgoing optical path of the polarization beam splitter; the optical path difference etalon is located in the polarization beam splitter In any outgoing light path or two outgoing light paths;

The polarizing beam splitter is used to divide the target light source through the collimator lens and the polarizer into two paths of S light and P light whose vibration directions are perpendicular to each other; the half-wave plate is used to adjust the vibration direction of the S light or the P light, so that The S light and the P light have the same vibration direction; the optical path difference etalon is used to adjust the optical path of the S light and/or the P light, so that a fixed optical path difference is generated between the S light and the P light; the three A plane mirror is used to reflect the S light and the P light, and finally reflect the S light and the P light with the same vibration direction and a fixed optical path difference to the non-polarization beam splitter; the non-polarization beam splitter is used to Both S light and P light with the same vibration direction and fixed optical path difference are reflected and transmitted to form interference fringes;

The interference fringes are imaged on the detector by the imaging mirror after being dispersed by the dispersion system.

Further, in order to ensure that the intensities of the two beams of light are basically the same after the polarization beam splitter is split, the angle between the vibration-transmitting direction of the polarizer and the vibration direction of the S light is 45°, and the S light is the polarization beam splitter. Reflected light; in order to make the vibration directions of the transmitted light and the reflected light consistent, the angle between the fast axis direction of the half-wave plate and the vibration direction of the incident light is 45°.

Further, the material of the optical path difference etalon is a uniaxial crystal or an amorphous material; the light is vertically incident on the surface of the optical path difference etalon.

Further, if the optical path difference etalon of uniaxial crystal material is set in the two outgoing optical paths after the polarization beam splitter, the surfaces of the two optical path difference etalons are both perpendicular to the corresponding incident light, and the crystal optical axis is parallel to crystal plane, and the half-wave plate is located in the optical path behind the optical path difference etalon.

Further, in order to adjust the period of the interference fringes, the inclination angle of at least one of the three plane mirrors can be adjusted.

Further, when an optical path difference etalon made of a uniaxial crystal material is set in both outgoing optical paths of the polarizing beam splitter, the optical path difference etalon is located in front of the flat reflection mirror whose tilt angle is adjustable.

Further, if the included angle between the plane mirror EF and the incident light is equal to 45°, the dispersion system includes two groups of dispersion units;

Each group of dispersion units includes a first cylindrical mirror, a second cylindrical mirror, a slit, a collimation system and a grating arranged in sequence along the optical path; the convergence directions of the first cylindrical mirror and the second cylindrical mirror are perpendicular to each other; The slit is located at the focal point of the second cylindrical mirror, and the length direction of the slit is consistent with the periodic direction of the interference fringes;

The two groups of interference fringes are respectively imaged at the slit through the first cylindrical mirror and the second cylindrical mirror in each group of dispersion units, and then collimated by the collimation system, and finally dispersed by the grating.

Further, if the angle between the plane reflection mirror EF and the incident light is not equal to 45°, the first cylindrical mirror, the second cylindrical mirror, the slit, the collimation system and the grating are sequentially arranged along the optical path of the dispersion system. ; The convergence directions of the first cylindrical mirror and the second cylindrical mirror are perpendicular to each other, the slit is located at the focal point of the second cylindrical mirror, and the length direction of the slit is consistent with the periodic direction of the interference fringes;

The two groups of interference fringes are simultaneously imaged at different positions in the length direction of the slit after passing through the first cylindrical mirror and the second cylindrical mirror, and then collimated by the collimation system, and finally dispersed by the grating.

The present invention also provides an imaging method based on the above-mentioned high-throughput, high-resolution, high-contrast polarization interference spectroscopy imaging device, comprising the following steps:

Step 1. After the target light source passes through the collimating lens and the polarizer, it enters the polarization beam splitter;

Step 2. The polarization beam splitter divides the target light source through the collimating lens and the polarizer into two paths of S light and P light whose vibration directions are perpendicular to each other and have the same intensity;

Step 3. The three plane mirrors reflect the S light and the P light in turn, and the half-wave plate is used to adjust the vibration direction of the S light or the P light, so that the S light and the P light have the same vibration direction; use the optical path difference etalon to adjust The optical path of the S light and/or the P light makes a fixed optical path difference between the S light and the P light; the three plane mirrors finally reflect the S light and the P light with the same vibration direction and the fixed optical path difference to Unbiased beam splitter;

Step 4. The non-polarized beam splitter reflects and transmits both the S light and the P light with the same vibration direction and a fixed optical path difference to form interference fringes;

Step 5. The interference fringes are imaged on the detector after being dispersed by the dispersion system.

Further, if the angle between the plane mirror EF and the incident light is equal to 45°, the step 5 is specifically:

The two groups of interference fringes are respectively imaged at the slit by the first cylindrical mirror and the second cylindrical mirror in each group of dispersion units, and then collimated by the collimation system, and finally imaged at two different detectors after being dispersed by the grating. on the device;

If the angle between the plane mirror EF and the incident light is not equal to 45°, the step 5 is specifically:

First, adjust the angle of the plane mirror EF so that the reflected beam and the other beam entering the dispersion system are not in the same plane; the reflected beam passing through the plane mirror EF and the other beam pass through the first cylindrical mirror and the second beam The cylindrical mirror is then imaged at different positions in the length direction of the slit, and then collimated by the collimation system, and finally imaged at different positions of the detector through the grating (64) dispersion.

The beneficial effects of the present invention are:

(1) In terms of luminous flux, the energy utilization rate of the imaging device of the present invention is improved.

Firstly, the asymmetrical structure design enables the original beam returning to the light source to be reused; secondly, due to the use of a polarizing beam splitter and a half-wave plate in the interferometer, the vibration directions of the two beams whose vibration directions are perpendicular to each other are the same, saving energy. went to the analyzer. Therefore, the energy utilization rate of the light source is improved, thereby also improving the sensitivity of the system.

(2) It has high stability.

Since the device adopts the design scheme of the common optical path, the optical paths of the two paths of light (except for the added fixed optical path difference) are basically the same, so the influence of external vibration and thermodynamic changes on the interference can basically be ignored. The fringes are more stable than non-common-path interferometers.

(3) It has high spectral resolution.

Since the device uses a grating after the interferometer, the spectral resolution of the system is determined by the grating. The appropriate grating can be selected according to the detection requirements. Compared with the traditional interference imaging spectrometer adding the emission slit or adding the optical path difference directly in the interferometer, it not only improves the energy utilization rate but also improves the contrast of the interference fringes.

(4) Has a high contrast ratio.

In the present invention, a polarizer is added before the interferometer, and by adjusting the angle of the polarizer, the intensities of the two beams of light after being split by the polarizing beam splitter are basically the same, and the use of the half-wave plate in the interferometer changes the vibration directions of the two beams of light. become consistent, so the contrast of the interference fringes can be improved. The combined use of the polarization beam splitter and the half-wave plate can reduce or eliminate the interference caused by multiple reflections or scattering of the two paths of light in the interferometer and further improve the contrast ratio.

(5) In the present invention, a fixed optical path difference is generated by adding an optical path difference etalon in the interferometer. According to the interference principle, it can be known that the optical path difference can amplify the phase change of the interference fringes. It is beneficial to improve the detection accuracy.

(6) In the present invention, a grating is used in the post-dispersion system to disperse the interference fringes along the wavelength direction. Since the periods of the interference fringes obtained at different wavelengths are different, the interference between lights of different wavelengths can be reduced after dispersion. The overlapping of the stripes, thereby improving the contrast of the system.

(7) In the present invention, two cylindrical mirrors are used after the interferometer, and the convergence directions of the two cylindrical mirrors are perpendicular to each other. The rear beam after exiting the interferometer is imaged at the slit after passing through two cylindrical mirrors. The focal length of the two cylindrical lenses can be designed according to the size of the slit, so that the light beam can pass through the slit with no or minimal loss of energy. Since the cylindrical mirror only changes the optical power in one direction, the two cylindrical mirrors can be used to control the optical power in two directions respectively. Therefore, light spots with different aspect ratios can be obtained by changing the focal length of the two cylindrical mirrors.

Description of drawings

1 is a schematic diagram of a polarization interference spectroscopy imaging device in Embodiment 1 of the present invention;

2 is a schematic diagram of a set of dispersion units used in the polarization interference spectroscopy imaging device in Embodiment 2 of the present invention;

The reference numbers in the figure are: 1-light source, 2-collimating mirror, 3-polarizer, 4-interferometer, 41-polarizing beam splitter, 42-plane mirror, 43-non-polarizing beam splitter, 44- Half-wave plate, 45-optical path difference etalon, 5-plane mirror EF, 6-dispersion system, 60-first cylindrical mirror, 61-second cylindrical mirror, 62-slit, 63-collimation system , 64-grating, 7-imaging mirror, 8-detector;

Detailed ways

The high-throughput, high-resolution, high-contrast polarization interference spectrum imaging device of the invention mainly includes three parts: a collimation system, an interferometer and a back dispersion system. The collimation system is used to collimate the light path entering the system. The interferometer adopts the Sagnac interferometer with asymmetric structure of the common optical path, which not only makes the original light returning to the light source can be used by the subsequent optical path, but also the optical path of the two paths in the interferometer is basically the same, which improves the luminous flux and stability of the system. The polarization beam splitter can be used for light splitting to obtain two polarized lights whose vibration directions are perpendicular to each other. A half-wave plate is added to one of the lights to make the vibration directions of the two lights consistent, avoiding the use of an analyzer and improving the energy. Utilization; high spectral resolution is achieved by adding a grating after the interferometer, and the use of the grating can disperse the incident light along the wavelength direction and improve the contrast of the interference fringes; the addition of a fixed optical path difference in the interferometer can amplify the interference fringes Therefore, the detection accuracy can be improved in detecting the radial velocity based on the phase change of the interference fringe.

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Example 1

As shown in FIG. 1 , the high-contrast, high-throughput, and high-resolution coherent dispersive spectroscopy imaging device in this embodiment is mainly composed of a collimating mirror 2, a polarizer 3, a Sagnac interferometer 4 with an asymmetric structure and a common optical path, a plane mirror EF5, The dispersion system 6 , the imaging mirror 7 and the detector 8 are constituted.

After the target light source passes through the collimating mirror 2 and the polarizer 3, it is incident on the Sagnac interferometer 4 with an asymmetric structure and a common optical path. The device 43 is composed of a half-wave plate 44 and an optical path difference etalon 45 located in the outgoing optical path of the polarization beam splitter 41 . First, the target light source is divided into two polarized lights whose vibration directions are perpendicular to each other by the polarization beam splitter, namely S light and P light, of which the reflected light is S light and the transmitted light is P light. It should be noted that the angle between the transmission direction of the polarizer and the vibration direction of the S light should be 45°, so that the intensity of the S light and the P light after passing through is consistent, and the contrast of the interference fringes is also ensured. The common optical path Sagnac interferometer with asymmetric structure enables the use of one light returning to the light source, and the optical paths of the two light paths are basically the same, which improves the luminous flux and stability of the system.

After passing through the polarization beam splitter 41, the S light passes through the mirrors AB, BC, and CD in sequence. Similar to the S light, the transmitted light P passes through the mirrors CD, BC and AB in sequence. In order to generate a fixed optical path difference between the two paths of the S light and the P light, a fixed optical path difference can be added to either optical path, or the optical path difference can be added to the two paths at the same time. The optical path difference in the interferometer can be generated by adding an optical path difference etalon to one of the paths, but it should be noted that if an optical path difference is added to any path, the optical path difference etalon 45 is set to the S light or P In the optical path, the material of the optical path difference etalon 45 can be either uniaxial crystal or amorphous; when selecting an amorphous material, the light is required to be vertically incident on the surface of the optical path difference etalon 45, the size of the optical path difference and the material The length of the crystal material is related to the refractive index; if the optical path difference etalon 45 of the crystal material is selected to be inserted into any optical path to obtain a fixed optical path difference, when the beam is incident vertically, the optical axis of the crystal can be either perpendicular to the crystal plane or perpendicular to the crystal plane. The crystal planes are parallel. In the first case, since birefringence will not occur, the propagation direction of the light will not change. When calculating the optical path difference, the refractive index selected is the refractive index (n _o ) of this type of normal light; for the second case, Since the incident light is linearly polarized light whose vibration direction is parallel to the incident plane or perpendicular to the incident plane, when the optical axis is parallel to the crystal plane, the propagation direction of the light will not change. The vibrational directions are perpendicular to each other, resulting in an inconsistent refractive index (no or _{ne )} , so inserting the crystal into the reflected and transmitted light creates a difference in the optical path difference. If the optical path difference is generated by adding the optical path difference etalon 45 of crystal material to the two paths of light at the same time, the two beams of light are required to be incident vertically, and the optical axis is parallel to the crystal plane, so that the two beams of light pass through the optical path difference etalon. The propagation direction remains unchanged, and the refractive indices of S light (n _o ) and P( _ne ) light in the optical path difference etalon are different, resulting in a fixed optical path difference (L*(n _{o -ne} ) ).

Figure 1 shows an example of an optical path difference etalon inserted in an amorphous material in the reflected light. The following description is based on this case, and other cases are similar to this case. After the reflected light passes through the plane mirror AB, it passes through the half-wave plate 44, and the angle between the fast axis direction of the half-wave plate 44 and the vibration direction of the incident light is 45°, so that the difference between the transmitted light and the reflected light can be reduced. Vibration is the same. Of course, the half-wave plate 44 can also be added to the transmitted light, for the same purpose as adding the reflected light. The polarization beam splitter is used to split the light to obtain two polarized lights whose vibration directions are perpendicular to each other. A half-wave plate is added to one of the lights to make the vibration directions of the two lights consistent, avoiding the use of an analyzer and improving the energy utilization rate. However, it should be noted that if two paths of light are to pass through the optical path difference etalon 45 of the crystal material at the same time, the half-wave plate 44 needs to be added after the two paths of light pass through the optical path difference etalon 45, so that light can be generated. difference.

After the two beams of light pass through the three plane mirrors 42 in sequence, the transmitted beam and the reflected beam pass through the non-polarizing beam splitter 43 again, so the transmitted beam and the reflected beam are respectively reflected and transmitted again to form four beams. Therefore, the light transmitted by the polarizing beam splitter 41 and then transmitted by the non-polarizing beam splitter 43 interferes with the light reflected by the polarizing beam splitter 41 and then reflected by the non-polarizing beam splitter 43. The light transmitted by 41 and then reflected by the non-polarizing beam splitter 43 interferes with the two-way light reflected by the polarizing beam splitter 41 and then transmitted by the non-polarizing beam splitter 43 .

Due to the asymmetric design of the interferometer, the interference light returning to the light source and the outgoing light from the light source have a certain displacement in space. Therefore, it can be effectively used after being reflected by the plane mirror EF5, so that the energy of the entire optical path can be utilized. rate increased.

It should be noted here that the period of the interference fringes can be adjusted by adjusting the inclination of any one of the three plane mirrors 42 . In Fig. 1, the inclination of the flat mirror CD is adjusted. Although this angle of inclination is small, it changes the direction of propagation of the beam and has to undergo three reflections, so this small amount is also amplified by a factor of 4. In order to facilitate the measurement and calculation of the optical path difference later, the light beam needs to pass through the surface of the optical path difference etalon 45 vertically, so we add the optical path difference etalon 45 to the reflected light. It should be noted that, if the optical path difference etalon 45 of the crystal material needs to be added to the two paths of light at the same time to generate the optical path difference, in order to accurately calculate the optical path difference, the optical path difference etalon 45 of the crystal material needs to be added to the optical path difference etalon 45 of the crystal material. Adjust the tilt angle of the flat mirror before.

In this embodiment, the dispersion system 6 includes two groups of dispersion units, and each group of dispersion units includes a first cylindrical mirror 60, a second cylindrical mirror 61, a slit 62, a collimation system 63 and a grating 64 arranged in sequence along the optical path; when After the light beam passes through the interferometer to generate two interference fringes, one of them is reflected by the plane mirror EF5 to the first group of dispersion units, and the other directly enters the second group of dispersion units. The two interference fringes pass through the first group of dispersion units respectively. The first cylindrical mirror 60 and the second cylindrical mirror 61 converge to the corresponding slit 62 after being compressed. The convergence directions of the first cylindrical mirror 60 and the second cylindrical mirror 61 are perpendicular to each other, and the distance between the two can be adjusted according to the required aspect ratio of the light spot, that is, the length of the light spot obtained by the combination of cylindrical mirrors with different focal lengths. The width ratio is different. The position of the slit 62 is at the focal point of the second cylindrical mirror 61, and the longitudinal direction of the slit is consistent with the periodic direction of the interference fringes. After passing through the slit 62, the interference fringes pass through the collimation system 63 and are incident on the grating 64, so that the interference fringes are dispersed along the wavelength direction, and the two dispersed beams are finally imaged on the detector 8 through the imaging mirror 7 respectively. In this embodiment, a CCD is used to detect device.

Embodiment 2

The two paths of interference light emitted from the interferometer in Fig. 1 have opposite phases, and the angle between the plane mirror EF5 and the incident light is 45°. If a set of dispersion units is used, the intensity of the two paths of light may be changed due to the opposite phases. Therefore, in Figure 1, two sets of dispersion units are used to disperse the two beams of light and image them on the detector. However, if the angle between the flat mirror EF5 and the incident light is not 45°, then we can use a set of dispersive cells, which will eventually image the two beams at different locations on the CCD. As shown in FIG. 2 , the dispersion system 6 of this embodiment includes a set of dispersion units, that is, a first cylindrical mirror 60, a second cylindrical mirror 61, a slit 62, a collimation system 63 and a grating 64 arranged in sequence along the optical path; the specific imaging The steps are: first, adjust the angle of the plane mirror EF so that the reflected light beam and the other light beam entering the dispersion system are not in the same plane; the reflected light beam passing through the plane mirror EF and the other light beam pass through the first cylindrical mirror It is then imaged at different positions along the length direction of the slit with the second cylindrical mirror, then collimated by the collimation system, and finally imaged at different positions of the detector through the grating 64 dispersion.

Claims (10)

1. A high-flux high-resolution high-contrast polarization interference spectrum imaging device is characterized in that: the device comprises a collimating mirror (2), a polaroid (3), an interferometer (4), a dispersion system (6), an imaging mirror (7) and a detector (8) which are arranged in a light path in sequence;

the interferometer (4) is a common-path Sagnac interferometer with an asymmetric structure, and comprises a polarization beam splitter (41), three plane reflectors (42) and a non-polarization beam splitter (43) which are sequentially arranged along a light path; the polarization beam splitter further comprises a half-wave plate (44) and an optical path difference etalon (45) which are arranged in the propagation light paths from the polarization beam splitter (41) to the non-polarization beam splitter (43); the half-wave plate (44) is positioned in any emergent light path of the polarization beam splitter (41); the optical path difference etalon (45) is positioned in any emergent light path or two emergent light paths of the polarization beam splitter (41);

the polarization beam splitter (41) is used for dividing a target light source passing through the collimating mirror (2) and the polaroid (3) into two paths of S light and P light with mutually vertical vibration directions; the half-wave plate (44) is used for adjusting the vibration direction of the S light or the P light, so that the S light and the P light have the same vibration direction; the optical path difference etalon (45) is used for adjusting the optical path difference of the S light and/or the P light, so that a fixed optical path difference is generated between the S light and the P light; the three plane mirrors (42) are used for reflecting the S light and the P light and finally reflecting the S light and the P light with the same vibration direction and fixed optical path difference to the non-polarizing beam splitter (43); the non-polarization beam splitter (43) is used for reflecting and transmitting S light and P light with the same vibration direction and fixed optical path difference to form interference fringes;

the interference fringes are dispersed by a dispersion system (6) and then imaged on a detector (8) through an imaging mirror (7).

2. A high throughput high resolution high contrast polarized interference spectroscopy imaging apparatus according to claim 1 wherein: an included angle between the transmission vibration direction of the polaroid (3) and the vibration direction of the S light is 45 degrees, wherein the S light is reflected light of the polarization beam splitter; the included angle between the fast axis direction of the half-wave plate (44) and the vibration direction of the incident light is 45 degrees.

3. The high throughput high resolution high contrast polarized interference spectroscopy imaging apparatus of claim 2, wherein: the optical path difference etalon (45) is made of a uniaxial crystal or an amorphous material; light is incident perpendicularly to the retardation etalon surface.

4. A high throughput high resolution high contrast polarized interference spectroscopy imaging apparatus according to claim 3 wherein: if the two paths of emergent light paths passing through the polarization beam splitter (41) are both provided with the optical path difference etalon (45) made of single-axis crystal materials, the surfaces of the two optical path difference etalons (45) are both vertical to corresponding incident light, the crystal optical axis is parallel to the crystal plane, and the half-wave plate (44) is positioned in the light path behind the optical path difference etalon (45).

5. The high throughput high resolution high contrast polarized interference spectroscopy imaging apparatus of claim 4, wherein: the inclination angle of at least one of the three plane reflectors (42) is adjustable.

6. The high throughput high resolution high contrast polarized interference spectroscopy imaging apparatus of claim 5, wherein: if the two paths of emergent light paths passing through the polarization beam splitter (41) are both provided with the optical path difference etalon (45) made of single-axis crystal materials, the optical path difference etalon (45) is positioned in front of the plane reflector with the adjustable inclination angle.

7. A high throughput high resolution high contrast polarized interference spectroscopy imaging apparatus according to any one of claims 1 to 5 wherein: if the included angle between the plane reflector EF (5) and the incident light is equal to 45 degrees, the dispersion system (6) comprises two groups of dispersion units;

each group of dispersion units comprises a first cylindrical lens (60), a second cylindrical lens (61), a slit (62), a collimation system (63) and a grating (64) which are sequentially arranged along a light path; the convergence directions of the first cylindrical mirror (60) and the second cylindrical mirror (61) are mutually vertical; the slit (62) is positioned at the focus of the second cylindrical lens (61), and the length direction of the slit (62) is consistent with the periodic direction of the interference fringes;

two groups of interference fringes are imaged at a slit (62) after passing through a first cylindrical lens (60) and a second cylindrical lens (61) in each group of dispersion units respectively, are collimated by a collimation system (63), and are dispersed by a grating (64).

8. A high contrast high throughput high resolution polarized interference spectroscopy imaging apparatus according to any one of claims 1 to 5 wherein: if the included angle between the plane reflector EF (5) and the incident light is not equal to 45 degrees, the dispersion system (6) comprises a first cylindrical mirror (60), a second cylindrical mirror (61), a slit (62), a collimation system (63) and a grating (64) which are sequentially arranged along the light path; the converging directions of the first cylindrical mirror (60) and the second cylindrical mirror (61) are mutually perpendicular, the slit (62) is positioned at the focus of the second cylindrical mirror (61), and the length direction of the slit (62) is consistent with the periodic direction of the interference fringes;

two groups of interference fringes are imaged at different positions in the length direction of the slit (62) after passing through the first cylindrical mirror (60) and the second cylindrical mirror (61) at the same time, collimated by the collimating system (63), and dispersed by the grating (64).

9. An imaging method based on the high-throughput high-resolution high-contrast polarization interference spectrum imaging device according to any one of claims 1 to 8, characterized by comprising the following steps:

step 1, a target light source is incident to a polarization beam splitter after passing through a collimating mirror and a polarizing film;

step 2, the polarization beam splitter divides the target light source which passes through the collimating mirror and the polaroid into two paths of S light and P light which have mutually vertical vibration directions and consistent intensity;

3, sequentially reflecting the S light and the P light by the three plane reflectors, and adjusting the vibration direction of the S light or the P light by using a half-wave plate to enable the S light and the P light to have the same vibration direction; adjusting the optical paths of the S light and the P light by using the optical path difference etalon to generate a fixed optical path difference between the S light and the P light; the three plane mirrors finally reflect the S light and the P light with the same vibration direction and fixed optical path difference to the non-polarization beam splitter;

step 4, the non-polarization beam splitter reflects and transmits the S light and the P light with the same vibration direction and fixed optical path difference to form interference fringes;

and 5, imaging the interference fringes on a detector after the dispersion of the dispersion system.

10. The method of imaging a high contrast high throughput high resolution polarized interference spectroscopy imaging apparatus of claim 9, wherein:

if the included angle between the plane mirror EF and the incident light is equal to 45 °, the step 5 specifically includes:

two groups of interference fringes are imaged at a slit after passing through a first cylindrical mirror and a second cylindrical mirror in each group of dispersion units respectively, then are collimated by a collimation system, and finally are imaged on two different detectors after being subjected to grating dispersion;

if the included angle between the plane mirror EF and the incident light is not equal to 45 °, the step 5 specifically includes:

firstly, adjusting the angle of a plane mirror EF to enable a reflected beam of the plane mirror EF and another beam entering a dispersion system not to be in the same plane; the reflected beam passing through the plane reflector EF and the other beam pass through the first cylindrical mirror and the second cylindrical mirror to be imaged at different positions in the length direction of the slit, are collimated by the collimating system, and are finally subjected to grating dispersion imaging at different positions of the detector.

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