CN116295838B - Astronomical polarization spectrometer system based on pupil splitting - Google Patents
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- G—PHYSICS
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- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
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- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
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Abstract
本发明提供了一种基于分光瞳的天文偏振光谱仪系统，包括准直镜、孔径光阑、拼接式四分之一波片、拼接式液晶偏振光栅、成像镜以及探测器；其中四分之一波片是由快轴成45°夹角的半片拼接而成，液晶偏振光栅是由光栅方向成90°夹角的半片拼接而成，通过分光瞳的方式，获得偏振光谱图像，实现偏振信息的调制与解调，可一次拍照获得信号的全部线性的Stokes参数，从而实现快速的天文光谱偏振成像。
The present invention provides an astronomical polarization spectrometer system based on pupil splitting, comprising a collimator, an aperture stop, a spliced quarter-wave plate, a spliced liquid crystal polarization grating, an imaging mirror and a detector; wherein the quarter-wave plate is spliced by half plates with fast axes forming an angle of 45°, and the liquid crystal polarization grating is spliced by half plates with grating directions forming an angle of 90°. By means of pupil splitting, a polarization spectrum image is obtained, modulation and demodulation of polarization information are realized, and all linear Stokes parameters of a signal can be obtained by taking a picture at one time, thereby realizing fast astronomical spectrum polarization imaging.
Description
Technical Field
The invention relates to the technical field of astronomical polarization measurement, in particular to an astronomical polarization spectrometer system based on a split pupil, which is used for astronomical polarization spectrum measurement.
Background
The nature of astronomical observation is the observation of electromagnetic waves, which has three fundamental characteristics, intensity, frequency and polarization. Of the optical and near infrared end instruments, photometry and spectroscopy instruments account for the vast majority, and these instruments do not obtain polarization information of the target. However, the physical mechanisms of scattering processes, the zeeman effect around the magnetic field source, and synchrotron radiation are all involved in observing polarized light of celestial objects. In the aspect of scientific application, the polarization spectrum measurement has wide application prospect in astronomical observation, and the polarization spectrum can provide important scientific basis for explanation and prediction of astronomical theoretical model research.
Currently, polarimeter designs all implement measurement of Stokes parameters by using a specific angle polarizer or polarizing beam splitter, and if full Stokes (I, Q, U) is to be measured, it is necessary to split the incident light into three or more angles. The common technical method is that the half-wave plate in front of the polaroid is rotated, the defects of the technology are that the rotation of the wave plate can cause the drift of light beams, so that the measurement accuracy and the synchronism are poor, the other method is that the polaroid with different polarization angles, such as three polaroids which are arranged on a Hubber telescope night vision camera, is adopted, the rotation angle interval of the polaroid is 60 degrees, the polaroid can be arranged on a filter rotating wheel, the light passing efficiency of the design is lower because the polaroid only allows 1/2 of light to pass through, a polarization beam splitter (such as Wollaston prism) can be used for replacing the polaroid, the light beam is divided into two beams, the light loss of a system is reduced, polarization information in two directions can be obtained by one photographing, all linear polarization information can be obtained by one rotation, and a plurality of angles are usually rotated in practical use so that the system error is eliminated by enough data.
However, whether a rotating wave plate or a design of polarizing plates with different angles is adopted, the complexity and instability of the system are increased by the existence of an electric control mechanical rotating mechanism, linear polarization components (Q, U) cannot be obtained at the same time, errors exist in calculation results under different exposure time sequences, synchronous calculation cannot be realized, and the accuracy of calculation results is reduced due to beam drift caused by mechanical rotation. The polarizer must incorporate a conventional grating or prism spectrometer, resulting in a large and complex overall size of the polarization spectrometer optical system.
Disclosure of Invention
The invention aims to provide a high-precision polarization measurement system for astronomical polarization spectrum measurement, which adopts the combination of polarization modulation and demodulation of a quarter wave plate and a liquid crystal polarization grating through the design of a split pupil, and can obtain all linear Stokes parameters Q, U with different wavelengths through one-time exposure so as to realize the polarization spectrum measurement of a celestial object.
According to a first aspect of the object of the present invention, there is provided a spectroscopic pupil based astronomical polarization spectrometer system comprising:
An entrance slit, a collimating mirror, an aperture stop, a tiled Quarter Wave Plate (QWP), a Liquid Crystal Polarization Grating (LCPG), an imaging mirror, and a detector, which are sequentially arranged along the light of the incident telescope;
The collimating lens is used for collimating light from the telescope, and the aperture diaphragm is used for limiting the caliber of the entrance pupil light beam;
the spliced quarter wave plate is formed by splicing half plates with fast axes forming an included angle of 45 degrees;
The liquid crystal polarization grating is formed by splicing half sheets with 90-degree included angles in the grating direction, and modulation and demodulation of polarization information are realized in a split pupil mode;
The light beam is collimated on the spliced quarter wave plate and the liquid crystal polarization grating through the collimating mirror after passing through the slit, and finally the modulated light is imaged on the detector through the imaging mirror.
The astronomical polarization spectrometer system is characterized in that a design combination of a spliced quarter wave plate and a liquid crystal polarization grating forms a polarization demodulation combination, the set of modulation combination can be arranged on a filter rotating wheel, if circularly polarized light is required to be measured, the circularly polarized light can be rotated out, as the polarization grating divides a pupil into two parts, the dispersion direction is vertical, each part is divided into left circularly polarized light and right circularly polarized light by the polarization grating, light is dispersed into four quadrants on the target surface of a detector, and finally the modulated light is imaged on the detector through an imaging lens.
In the example of the invention, based on the design of the split pupil, linear Stokes parameters can be obtained at the same time by one exposure, and the traditional polarization spectrometer needs to measure the spectrum intensity under different modulation modes for a plurality of times to obtain the Stokes parameters, thereby greatly reducing the influence of atmospheric turbulence on actual observation data and effectively improving the observation efficiency.
In other examples, the astronomical polarization spectrometer system may directly measure the spectrum of the circularly polarized component when the tiled quarter wave plate is removed, thereby measuring the full Stokes parameter, and thus the astronomical polarization spectrometer system may be configured with two modes of operation.
As an alternative example, the astronomical polarization spectrometer system based on the split pupil comprises a telescope focal plane light passing slit along the optical axis direction of the instrument, a collimating mirror, an aperture diaphragm, a spliced quarter wave plate, a spliced liquid crystal polarization grating, an imaging mirror and a detector which are sequentially arranged along the optical axis direction;
The split-type liquid crystal polarization grating is formed by split-type half-plates with a fast axis forming an included angle of 45 degrees, and the split-type liquid crystal polarization grating is formed by split-type half-plates with a grating direction forming an included angle of 90 degrees;
The combination of the spliced quarter wave plate and the spliced liquid crystal polarization grating realizes modulation and demodulation of polarization information in a split pupil mode;
the light beam from the telescope passes through the slit, is collimated by the collimating lens, then is projected on the spliced quarter wave plate and the spliced liquid crystal polarization grating, and is modulated by the imaging lens and then is imaged to the detector positioned at the focal plane position of the imaging lens.
As an alternative example, the split quarter wave plate has one fast axis parallel to the horizontal direction and the other fast axis at 45 ° to the horizontal direction. The working wave band range of the spliced quarter wave plate is 325nm-1100nm.
As an alternative example, the spliced liquid crystal polarization grating is formed by splicing two pieces of liquid crystal polarization gratings with the line directions mutually perpendicular, one half of the line directions are at-45 degrees with the horizontal direction, and the other half of the line directions are at 45 degrees with the horizontal direction. The spliced liquid crystal polarization grating (5) is made of liquid crystal polymer birefringent materials.
As an alternative example, a combination of a tiled quarter wave plate and a tiled liquid crystal polarization grating is mounted on an adjustable filter rotator wheel. When the circularly polarized light needs to be measured, the spliced quarter wave plate QWP can be rotated out, and as the spliced liquid crystal polarization grating divides the pupil into two parts and the dispersion direction is vertical, each part is divided into left circularly polarized light and right circularly polarized light by the polarization grating, light is dispersed into four quadrants on the target surface of the detector. And finally, imaging the modulated light on a detector through an imaging lens.
As an alternative example, in a polarization modulation mode formed by a spliced quarter wave plate and a spliced liquid crystal polarization grating, an ultra-achromatic spliced quarter wave plate is configured in front of the spliced liquid crystal polarization grating, when the fast axis direction of the spliced quarter wave plate is placed in parallel with the line direction of the spliced liquid crystal polarization grating and forms 45 degrees, based on a jones matrix in polarization optics, after a light beam passes through the spliced quarter wave plate and the spliced liquid crystal polarization grating, based on the magnetic field distribution of positive and negative first order parts of diffraction, the diffraction efficiency of the combination of the spliced quarter wave plate and the spliced liquid crystal polarization grating is obtained through settlement, so that the result of subtraction of the diffraction efficiency of the positive and negative first order efficiency and addition of the positive and negative first order efficiency under different angle combination forms is obtained, and a normalized calculation formula of Q 'and U' is obtained through division of the fast axis direction and the fast axis direction of the spliced quarter wave plate and the spliced liquid crystal polarization grating:
Wherein η -1 represents the negative diffraction efficiency of the light beam after passing through the spliced quarter wave plate and the spliced liquid crystal polarization grating, η +1 represents the positive diffraction efficiency of the light beam after passing through the spliced quarter wave plate and the spliced liquid crystal polarization grating, and Q 'and U' represent normalized linear polarization components Q and U, respectively.
Therefore, based on the polarization demodulation mode of the design combination of the spliced quarter wave plate and the liquid crystal polarization grating, when the astronomical polarization spectrometer system is used, all linear Stokes polarization parameters Q and U of a target can be obtained without delay and optical offset through one exposure, and when the spectrum of circularly polarized light is measured, the spliced quarter wave plate can be rotated out (namely moved out), so that the measurement of a component V of circularly polarized light is directly realized, the measurement of all Stokes parameters is further carried out, and the detection efficiency is greatly improved.
Compared with the prior art, the astronomical polarization spectrometer system provided by the invention is based on the design scheme of the spliced quarter wave plate and the liquid crystal polarization grating (spliced QWP+LCPG combination), namely the snapshot type linear Stokes parametric polarization spectrometer, and has high observation efficiency. LCPG replaces polaroid and common grating, further reduces light loss, and the system has no mechanical rotation optical element, avoids measurement accuracy reduction caused by beam jitter and drift, and simultaneously obtains all linear Stokes polarization parameters Q and U of the target without delay and optical offset by one exposure, thereby greatly reducing the influence of atmospheric turbulence on actual observation data and effectively improving observation efficiency.
Meanwhile, the astronomical polarization spectrometer system does not adopt the traditional grating structure design, has small physical size of the instrument and simple system, reduces the research and development period and cost, can be used as an access instrument for observing in a butt joint way with a small caliber telescope or for carrying out spectrum polarization inspection or long-time polarization monitoring on certain special stars by forming Robot Spectropolarimeter with the small caliber telescope, is compact and has no mechanical movement characteristic, and is very suitable for polarized spectrum measurement of astronomical targets by a space astronomical instrument.
It should be understood that all combinations of the foregoing concepts, as well as additional concepts described in more detail below, may be considered a part of the inventive subject matter of the present disclosure as long as such concepts are not mutually inconsistent. In addition, all combinations of claimed subject matter are considered part of the disclosed inventive subject matter.
The foregoing and other aspects, embodiments, and features of the present teachings will be more fully understood from the following description, taken together with the accompanying drawings. Other additional aspects of the invention, such as features and/or advantages of the exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of the embodiments according to the teachings of the invention.
Drawings
The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
Fig. 1 is a schematic diagram of an astronomical polarization spectrometer system according to an example embodiment of the present invention.
Fig. 2 is a schematic diagram of QWP and LCPG according to an exemplary embodiment of the present invention.
Fig. 3 is a schematic illustration of a polarized spectral image obtained by a detector of an exemplary embodiment of the present invention.
The meaning of the individual reference numerals in the figures is as follows:
slit 1, collimating mirror 2, aperture diaphragm 3, spliced quarter wave plate 4, spliced liquid crystal polarization grating 5, imaging mirror 6 and detector 7.
Detailed Description
For a better understanding of the technical content of the present invention, specific examples are set forth below, along with the accompanying drawings.
Aspects of the invention are described in this disclosure with reference to the drawings, in which are shown a number of illustrative embodiments. The embodiments of the present disclosure are not necessarily intended to include all aspects of the invention. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, may be implemented in any of a number of ways, as the disclosed concepts and embodiments are not limited to any implementation. Additionally, some aspects of the disclosure may be used alone or in any suitable combination with other aspects of the disclosure.
The invention is one of the achievements of the project 'Snapshot type linear Stokes parameter polarization spectrometer key technical research' (12073056) on the national natural science foundation.
For a better understanding of the technical content of the present invention, specific examples are set forth below, along with the accompanying drawings.
With reference to fig. 1, the astronomical polarization spectrometer system according to the embodiment of the invention aims to realize spectrum measurement of an astronomical telescope observation beam and obtain linear polarization component Q, U of the spectrum, so that linear polarization degree information and polarization azimuth angle information of an observation target can be obtained according to Q, U component, and the astronomical polarization spectrometer system has very important scientific value for researching the characteristics of the target.
Theoretical analysis of the snapshot type linear Stokes parameter measuring method with different wavelengths under the condition of ensuring the compactness of the system and the simple optical structure, the snapshot type polarization measuring method has the technical difficulty that two linear parameters of Q, U are obtained at the same time through one exposure, and the other technical difficulty that the Stokes parameters with different wavelengths are also obtained.
The astronomical polarization spectrometer system design as shown in the example of fig. 1 comprises a telescope focal plane light passing slit 1 along the optical axis direction of the instrument, a collimating mirror 2, an aperture diaphragm 3, a spliced quarter wave plate 4, a spliced liquid crystal polarization grating 5, an imaging mirror 6 and a detector 7 which are sequentially arranged along the optical axis direction.
The collimator lens 2 is used for collimating the light beam from the telescope.
The aperture stop 3 is used to limit the aperture of the entrance pupil beam.
The spliced Quarter wave plate 4 (QWP for short) is formed by splicing half plates with fast axes forming an included angle of 45 degrees.
The spliced liquid crystal polarization grating 5 (Liquid crystal polarization prating, LCPG for short) is formed by splicing half pieces with an included angle of 90 degrees in the grating direction.
The combination of the spliced quarter wave plate 4 and the spliced liquid crystal polarization grating 5 realizes modulation and demodulation of polarization information in a split pupil mode.
Thus, the light beam from the telescope passes through the slit, is collimated by the collimator lens 2, is projected onto the split quarter wave plate 4 and the split liquid crystal polarization grating 5, and is then imaged by the imaging lens 7 to the detector 7 located at the focal plane position of the imaging lens 7.
According to the invention, the design of all linear Stokes polarization parameters is obtained based on one-time exposure, the optimal design selection is carried out, and the polarization spectrum measurement is realized by combining a scheme of a split pupil with a combination mode of a quarter wave plate and a liquid crystal polarization grating.
After the light beam from the slit is collimated by a collimating mirror 2, the size of the collimated light beam cannot exceed the clear aperture (50 mm) of the QWP, the collimated light enters a quarter wave plate after passing through a diaphragm, the quarter wave plate is formed by splicing wave plates with fast axes forming an angle of 45 degrees, one fast axis is parallel to the horizontal direction, and the other fast axis forms an angle of 45 degrees with the horizontal direction. Meanwhile, the working wave band range of the achromatic quarter wave plate is 325nm-1100nm, the phase delay precision is < lambda/100, the transmittance is >90%, and the surface shape RMS is < lambda/4@633nm.
After passing through QWP, the light enters a spliced Liquid Crystal Polarization Grating (LCPG) for polarization demodulation and color separation, and the liquid crystal polarization grating is formed by splicing two pieces of liquid crystal polarization grating with mutually perpendicular line directions.
As shown in fig. 2. Half of the liquid crystal polarization gratings are arranged at an angle of-45 degrees with the horizontal direction, the other half of the liquid crystal polarization gratings are arranged at an angle of 45 degrees with the horizontal direction, the substrates are made of N-BK7 glass, the liquid crystal polarization gratings are made of liquid crystal polymer birefringent materials, the aperture is 50mm, the working temperature is-20 ℃ to 80 ℃, the phase period is 5 mu m, the number of the lines is 200, and the diffraction efficiency is more than 98%.
The QWP+LCPG modulated light is finally converged on the detector by an imaging mirror, the split pupil design is such that the light in the lower left corner is split into linear polarizations in two directions of 0 DEG and 90 DEG, and the light in the upper right corner is split into linear polarizations in two directions of 45 DEG and 135 DEG, and since the polarization grating splits the pupil into two parts with the dispersion directions being perpendicular, each part is split into + -1 stage by the polarization grating, the light is dispersed into four quadrants on the detector target surface.
Further, the Q polarization component of the target can be obtained by subtracting the intensities of one three quadrants, and the U polarization component can be obtained by subtracting the intensities of two four quadrants.
In the astronomical polarization spectrometer system, based on the polarization modulation mode of QWP+LCPG, the arrangement direction of liquid crystal molecules in LCPG is linearly changed along with space coordinates, and in one grating period, the azimuth angle of the liquid crystal molecules is changed by 180 degrees. In further combination with the jones matrix analysis, each optical element has a jones matrix, and the LCPG jones matrix is represented as follows:
Wherein the method comprises the steps of For the rotation matrix, a=1, b=exp (iΓ), where Γ is the birefringence phase retardation of the liquid crystal, pi Δnd/λ, λ represents the wavelength, without energy loss of absorption and scattering.
Substituting parameters and a rotation matrix under the condition of no absorption and scattering energy loss according to a transmissivity matrix formula of LCPG, and obtaining after finishing:
When the incident beam passes through the LCPG, the incident beam is divided into three diffraction orders, namely a zero order and a positive and negative first order, wherein the diffraction efficiency of the zero order and the positive and negative first order can be calculated by (1.2), the polarization states of the positive and negative first order emergent light are right-handed and left-handed circularly polarized light, and the polarization states of the positive and negative first order emergent light are right-handed and left-handed circularly polarized light.
The basic principle of polarization modulation and demodulation of the qwp+lcpg combination is as follows, in conjunction with fig. 1:
Assuming that the electromagnetic fields of the incident light are E x and E y respectively, the electromagnetic field of the emergent light after passing through PG can be calculated, and the diffraction efficiencies of zero order and positive and negative orders can be obtained respectively according to the definition of Stokes parameters:
The normalized quantity of the Stokes circular polarized light, i.e., V' =v/I 0, can be obtained according to (1.4), and the circular polarized light component of the Stokes can be obtained by adding the light intensity of the positive and negative light intensity minus ratio, so that in the system design of the invention, the polarization spectrometer can directly measure the circular polarized light without adding QWP.
In the embodiment of the invention, in combination with the requirement of all measurement of one exposure of the linear polarization component Q, U shown in fig. 1, in order to realize the unique advantage of one exposure and simultaneously obtain all linear Stokes components, so as to reduce the influence of atmospheric turbulence on polarization spectrum measurement and improve the observation efficiency, the polarization spectrometer system of the invention proposes a design scheme based on a Split pupil (Split-pupil), wherein super achromatic QWP is introduced in front of the LCPG, namely two halves of QWP splice (PATTERNED QWP), the fast axis of which forms an included angle of 45 degrees, and the grating direction of the corresponding two halves of LCPG splice forms an included angle of 90 degrees, as shown in fig. 2.
In a polarization modulation mode formed by a spliced quarter wave plate 4 and a spliced liquid crystal polarization grating 5, an ultra-achromatic spliced quarter wave plate 4 is configured in front of the spliced liquid crystal polarization grating 5, when the fast axis direction of the spliced quarter wave plate 4 is placed in parallel with the line direction of the spliced liquid crystal polarization grating 5 and forms 45 degrees, based on a Jones matrix in polarization optics, when a light beam passes through the spliced quarter wave plate 4 and the spliced liquid crystal polarization grating 5, based on the magnetic field distribution of positive and negative first-order parts of diffraction, the diffraction efficiency of the combination of the spliced quarter wave plate 4 and the spliced liquid crystal polarization grating 5 is obtained through settlement, and therefore, the result of subtraction of the diffraction efficiency of the positive and negative first-order efficiency under different angle combination forms is obtained, and normalized Q 'and U' are obtained through division of the fast axis direction and the fast axis direction of the spliced quarter wave plate 4 and the line direction of the spliced liquid crystal polarization grating 5:
Wherein η -1 represents the negative diffraction efficiency of the light beam after passing through the spliced quarter wave plate 4 and the spliced liquid crystal polarization grating 5, η +1 represents the positive diffraction efficiency of the light beam after passing through the spliced quarter wave plate 4 and the spliced liquid crystal polarization grating 5, and Q 'and U' represent normalized linear polarization components Q and U, respectively.
Thus, from the Q, U component obtained, linear polarization degree information and polarization azimuth angle information of the observation target can be obtained.
In a specific embodiment, by introducing a super-achromatic QWP prior to LCPG:
when the fast axis direction of the spliced quarter wave plate 4 is placed in parallel with the scribing direction of the spliced liquid crystal polarization grating 5, the jones matrix thereof is expressed as:
when the light beam passes through the spliced quarter wave plate 4 and the spliced liquid crystal polarization grating 5, only the magnetic field distribution of the positive and negative first-order parts is calculated, and the expression is as follows:
according to equation 1.6, the combined diffraction efficiencies are obtained as:
when the fast axis direction of the spliced quarter wave plate 4 and the line direction of the spliced liquid crystal polarization grating 5 are 45 degrees, the diffraction efficiency of the combination is obtained as follows:
wherein E in represents the incident light intensity;
T represents the transmission matrix of the spliced liquid crystal polarization grating 5, and is expressed as:
Wherein, For the rotation matrix, a=1, b=exp (iΓ), where Γ is the birefringent phase retardation of the liquid crystal polymer birefringent material, pi Δnd/λ, λ represents the wavelength, ignoring the energy loss of absorption and scattering.
Based on formulas (1.7) and (1.8), normalized Q 'and U' can be obtained by subtracting the diffraction intensities of positive and negative orders and dividing the diffraction intensities by the diffraction intensity of positive and negative orders under different angle combination forms:
As described above, η -1 and η +1 represent the negative and positive diffraction efficiencies of the light beam after passing through the split quarter wave plate 4 and the split liquid crystal polarization grating 5, respectively.
From the obtained Q, U components, linear polarization degree information (Fraction of linear polarization) and polarization azimuth angle information (Polarization angle) of the observation target can be obtained.
Therefore, all linear Stokes polarization parameters Q and U of the target can be obtained without delay and optical offset through one-time exposure, so that quick astronomical spectrum polarization imaging is realized, the influence of atmospheric apparent degree on polarization measurement is effectively eliminated, and the measurement precision and efficiency are greatly improved. The measuring system is designed without mechanical moving parts, the optical-mechanical system is simple in structure and high in light transmission efficiency, the optical-mechanical system is suitable for being used as an access instrument (Visiting instrument) for being in butt joint observation with a telescope, especially for being in butt joint with a small-caliber telescope to carry out polarization spectrum inspection on astronomical monitoring (such as a Yao variant and the like) for a long time, namely Robot Spectropolarimeter, and meanwhile, the miniaturized instrument is very beneficial to being applied to space astronomical polarization spectrum measurement.
In an alternative embodiment, as shown in connection with fig. 1, a combination of a tiled quarter wave plate 4 and a tiled liquid crystal polarization grating 5 is mounted on an adjustable filter rotator wheel. Therefore, if the circularly polarized light needs to be measured, the spliced quarter wave plate 4 can be rotated out (moved out of the light path), so that the parameter V of the circularly polarized light can be measured, and all Stokes parameters can be measured.
Therefore, the astronomical polarization spectrometer provided by the invention can be configured into two working modes by a system, wherein one working mode is the combined use of QWP+LCPG, so that the measurement of linear polarization component QU is realized, and in the other working mode, the measurement of polarization component V of circularly polarized light can be realized by moving out the QWP.
While the invention has been described with reference to preferred embodiments, it is not intended to be limiting. Those skilled in the art will appreciate that various modifications and adaptations can be made without departing from the spirit and scope of the present invention. Accordingly, the scope of the invention is defined by the appended claims.
Claims (7)
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| CN111595442B (en) * | 2020-05-08 | 2025-02-11 | 中国科学院西安光学精密机械研究所 | Snapshot type polarization spectrum imaging method and device |
| CN112781728B (en) * | 2020-12-30 | 2024-03-19 | 北京理工大学重庆创新中心 | Full-polarization hyperspectral imaging method capable of accurately solving and combining compressed sensing |
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