CN117490847A - High-flux high-resolution static Fourier transform spectrum measurement method - Google Patents
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/28—Investigating the spectrum
- G01J3/45—Interferometric spectrometry
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/02—Details
- G01J3/0205—Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows
- G01J3/0208—Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/45—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods
Abstract
The invention relates to a high-flux high-resolution static Fourier transform spectrum measurement method, which comprises the following steps: step S1: introducing light to be measured into a static Fourier transform spectrum measurement system through a collimating lens; step S2: the output interference fringes of the static Fourier transform spectrum measurement system are led out to an area array detector; step S3: the image processing system is used for guiding the pictures obtained by the area array detector into the Fourier transform system; step S4: and calculating target spectrogram information through Fourier transformation. The invention removes the slit to improve the luminous flux of the system, and the focal length of the rear lens can be smaller by matching with virtual-real conversion, thereby reducing the distance from the rear lens and the area array detector to the beam splitter, further reducing the occupied volume of the system, enabling the area-limited area array detector to receive more interference fringes, improving the spectral resolution of the system and solving the problems of small luminous flux and low resolution of the traditional static Fourier transform spectral measurement method.
Description
Technical Field
The invention relates to the field of Fourier transform spectrum measurement methods, in particular to a high-flux high-resolution static Fourier transform spectrum measurement method.
Background
The Fourier transform spectrum measurement technology is currently applied to the fields of military investigation, space remote sensing, geological exploration, biomedicine and the like, has the advantages of high flux, high resolution and high stability, and is an effective means for detecting and analyzing the components of the target substances. The high-resolution spectrum analysis is utilized to accurately measure the target, and the method has important application value for cosmic substance analysis, food safety detection and biomedical detection. The static Fourier transform spectrometer is improved in motion performance, so that the static Fourier transform spectrometer can work independently in a working environment with more complex detection conditions. By detecting the interference phenomenon through the area array detector, different spatial positions can be detected at the same time, and the detection degree of interference information is perfected.
The fourier transform spectrometer based on spatial modulation is also called a Static Fourier Transform Spectrometer (SFTS), and can acquire interference information of a target spectrum in a two-dimensional space, and is more perfect in terms of interference information than the time modulation fourier transform spectrometer. With the advent and intensive research of Michelson type, mach-zehnder type, sagnac type and SFTS based on the birefringence characteristics of crystals, the development of static fourier transform spectrometers is gradually perfected. In the early years, the manufacturing of multi-stage stepped micro-mirrors is limited due to insufficient technological level, and most researchers choose to simulate the system; in recent years, with the development of micro-optical electro-mechanical system (MOEMS) technology, the stepped reflector can reach the millimeter-level transverse dimension and the submicron height precision, and the development of a spectrometer is promoted; at present, the Michelson SFTS working in the infrared band has the resolution of 194cm -1 But it limits the adjustment of the shearing distance so that the resolution is not adjustable and the working resolution is relatively single. The Sagnac SFTS structure is the simplest, and the current resolution can reach 30cm -1 The working principle is that a dove prism is added between two plane mirrors to realize the shearing distanceAdjustability, thereby effecting a change in resolution by controlling movement of the mirrors to change the shearing distance. Mach-zehnder SFTS uses plane mirrors to emit light rays after beam splitting into parallel light rays with a certain interval distance so as to meet interference conditions, wherein the plane mirrors are arranged at 45 degrees, the requirements on angle precision are high, the operation is complex, the spectral bandwidth which can be realized by the currently proposed on-chip Fourier transform spectrometer array structure is above 150nm, and the spectral resolution is at least 40cm -1 . For SFTS based on the crystal birefringence characteristics, researchers have proposed an ultra-compact SFTS based on the development of birefringent retarder arrays, with a spectral resolution of about 25cm -1 . However, such SFTS is complex in structure and operation, involves complex devices such as polarizers, analyzers, birefringent crystals, etc., and slits in the structure can limit the luminous flux. Meanwhile, the detection accuracy cannot be further improved due to the limitation of the volume of the system and the area of the detector.
Most of the existing structures are complex in design, working principle and the like, the compactness and the resolution are difficult to reach higher level, and the spectrum measuring instrument is required to have higher flexible portability, sensitivity and resolution for occasions such as marine shipborne experiments, aerospace measurement, material detection and the like. Thus, increasing resolution, increasing luminous flux, reducing operational complexity, and increasing system compactness have become a direction of development for static fourier transform spectral measurements.
Disclosure of Invention
The invention aims to solve the problems, and provides a high-flux high-resolution static Fourier transform spectrum measuring method which solves the problems of small luminous flux and low resolution of the existing static Fourier transform spectrum measuring method.
A high-throughput high-resolution static fourier transform spectroscopy method comprising the steps of:
step S1: introducing light to be measured into a static Fourier transform spectrum measurement system through a collimating lens;
step S2: the output interference fringes of the static Fourier transform spectrum measurement system are led out to an area array detector;
step S3: the image processing system is used for guiding the pictures obtained by the area array detector into the Fourier transform system;
step S4: and calculating target spectrogram information through Fourier transformation.
On the basis of the technical scheme, the static Fourier transform spectrum measurement system comprises a front lens, a first pyramid, a second pyramid, a beam splitter, a rear lens and an area array detector, wherein the collimating lens, the front lens and the beam splitter are sequentially arranged from left to right, the centers of the collimating lens, the front lens and the beam splitter are all located on a first main optical axis, the first pyramid and the second pyramid are respectively located on the upper side and the right side of the beam splitter, the rear lens is located on the lower side of the beam splitter, and the area array detector is located on the lower side of the rear lens.
On the basis of the technical scheme, the optical splitter further comprises a cylindrical lens, the cylindrical lens is located between the rear lens and the area array detector, and the centers of the beam splitter, the rear lens, the cylindrical lens and the area array detector are located on the second main optical axis.
On the basis of the technical scheme, the pyramid pair of beam splitting mirrors move in the left-right direction, and the pyramid pair of beam splitting mirrors move in the up-down direction.
On the basis of the technical scheme, the step S2 comprises the following steps:
step S21: collimating the light to be detected through a collimating lens to obtain parallel light, converging the parallel light in a front lens, splitting the parallel light by a beam splitter, and then respectively entering a first pyramid and a second pyramid, and respectively forming a converging point I and a converging point II at the lower side of the pyramid and the left side of the second pyramid;
step S22: carrying out ray tracing on two beams of light split by a beam splitter, moving the first pyramid in the left-right direction and the second pyramid in the up-down direction until a converging point after the light passes through the first pyramid coincides with a virtual object point corresponding to a converging point after the light passes through the second pyramid;
step S23: moving the pyramid to the left side of the second main optical axis and the pyramid to the upper side of the first main optical axis, wherein the distance of the first pyramid moving leftwards and the distance of the second pyramid moving upwards are bothAt this time, the light emitted by the first convergence point and the second convergence point passes through the beam splitter and the rear lens to form two parallel light beams with a certain included angle, and the two parallel light beams are projected to the area array detector. Namely, a first convergence point and a second convergence point are two phase-interference light source points;
and placing virtual object points corresponding to the first convergence point and the second convergence point on a front focal plane of the rear lens, wherein the first convergence point and the second convergence point are in mirror symmetry relative to a second main optical axis, and light passing through the first convergence point and light passing through the second convergence point are subjected to collimation action of the rear lens to form interference fringes at an area array detector, wherein the area array detector is positioned on the rear focal plane of the rear lens.
On the basis of the technical scheme, the first converging point of the front lens is located between the first pyramid and the beam splitter, and the second converging point of the front lens is located between the second pyramid and the beam splitter. The static Fourier transform spectrum measuring system has no luminous flux loss caused by a slit, and virtual object points of the first converging point and the second converging point are positioned on the front focal plane of the rear lens, and the focal length of the rear lens is reduced due to the characteristics of the positions of the two points, so that the whole volume of the system is reduced.
On the basis of the technical scheme, the front lens plays a role in converging, the rear lens plays a role in collimating to generate two parallel light beams with a certain included angle, the transmission and reflection beam splitting ratio of the beam splitting lens is 1:1, and the included angle between the beam splitting lens and the main optical axis is 45 degrees.
On the basis of the technical scheme, the step S3 comprises the following steps:
step S31: the area array detector acquires a two-dimensional picture comprising interference fringes;
step S32: and (3) intercepting the two-dimensional picture, respectively averaging the columns in the two-dimensional picture, and replacing column values with the obtained average value. Steps S31 and S32 may be repeated to perform the result averaging process in order to improve the signal-to-noise ratio.
Based on the above technical solution, the step S4 includes:
when two pyramids each moveThe incident and the outgoing light of each pyramid will be separated +>I.e. when the pyramids are moved by the same distance +.>Time shear distance->。
Arbitrary position coordinates of area array detectorThe optical path difference is->And->Final optical path difference and arbitrary position coordinates +.>The relation of->Wherein->Focal length of the rear lens;
maximum optical path difference variation:wherein->N is the number of pixels in the transverse direction on the detector, and s is the pixel spacing (size) for the included angle between the connecting line of the virtual object point of the second convergence point and the center of the rear lens and the second main optical axis;
the information listing several key parameters in the present invention is as follows:
spectral resolutionThe rate is as follows:；
for wavelengthMaximum interference order: />；
Maximum spatial frequency:；
sampling frequency of detector:；
sampling interval:；
pixel spacing:；
the interferogram light intensity expression is as follows:wherein->The beam is represented as a beam,a spectral density function representing the light intensity, since only +.>It is only practical, so the integral lower limit is 0, and the spectrum curve and the interferogram curve are a pair of Fourier transformation pairs;
finally through the formulaObtaining the light to be measuredIn (2), whereinThe position coordinates on the area array detector corresponding to the maximum optical path difference.
On the basis of the technical scheme, the method further comprises a step S24, wherein the step S24 is positioned after the step S23; the step S24: a fixed wavelength laser is used for shear-distance correction to determine the current shear-distance magnitude and the resolution that can be achieved. And determining the required optimal resolution by the test environment, and repeatedly adjusting the shearing distance to achieve the optimal resolution under the test environment so as to achieve the optimal sensitivity of measurement. The invention has the following advantages:
1. the spectrum measuring method is suitable for weak light signal measurement with higher resolution and sensitivity requirements, has the advantages of simple operation, stable performance, good repeatability and the like, and is suitable for substance analysis and environment monitoring under complex conditions;
2. the SFTS has the advantages of high signal-to-noise ratio, high luminous flux, miniaturization and the like, is simple to calculate and debug, does not need moving parts in independent operation, is convenient to carry, and has higher precision and stability compared with the traditional static Fourier transform spectrum static measurement method;
3. the resolution of the spectrum measuring system is continuously adjustable, the shearing distance and the resolution are changed by moving the first pyramid and the second pyramid, the spectrum measuring system can adapt to the optimal resolution required by different measuring occasions, and the spectrum measuring system has high flexibility;
4. compared with the traditional SFTS and a beam-splitting spectrometer, the system improves the luminous flux by removing the slit, and the focal length of the rear lens can be smaller by matching with virtual-real conversion, so that the distance from the rear lens to the area array detector to the beam splitter is reduced, the occupied volume of the system is further reduced, more interference fringes can be received by the area-limited area array detector, and the spectral resolution of the system is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It is apparent that the drawings in the following description are only one embodiment of the present invention, and that other embodiments of the drawings may be derived from the drawings provided without inventive effort for a person skilled in the art.
Fig. 1: the structure of the invention is schematically shown;
fig. 2: the invention discloses an equivalent model schematic diagram of a part of light paths.
Detailed Description
The invention is further illustrated by the following figures and examples:
embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
Embodiment one:
as shown in fig. 1 and 2, the present embodiment provides a high-flux high-resolution static fourier transform spectrum measurement method, and the light path-extending structure thereof sequentially includes a collimating lens 2, a front lens 3, a first pyramid 4, a second pyramid 5, a beam splitter 6, a rear lens 7, a cylindrical lens 8, and an area array detector 9.
Referring to fig. 1, the arrow direction in fig. 1 indicates the ray tracing direction, the horizontal dotted line in fig. 1 indicates the primary optical axis one, and the vertical dotted line indicates the primary optical axis two.
Referring to fig. 1, as can be seen from the optical path difference between the two light beams after the light beam tracking, the first convergence point 10 and the second convergence point 11 of the light beam passing through the front lens 3 and the beam splitter 6 are respectively the light emitting points of the two-phase light source, and the interference fringes will be generated when the light emitted from the two points is projected onto the area array detector 9 through the beam splitter 6 and the rear lens 7.
The experiment firstly collimates the light beam 1 to be detected through the collimating lens 2 to obtain parallel light, the parallel light enters the front lens 3 to be converged, the converged light beam enters the first pyramid 4 and the second pyramid 5 after being split by the beam splitter 6, and a converging point I10 and a converging point II 11 are formed on the lower side and the left side of the first pyramid 4 and the second pyramid 5 respectively. The distance between the first pyramid 4 and the second pyramid 5 and the beam splitter 6 is equal, and the vertexes of the first pyramid 4 and the second pyramid 5 are respectively positioned on the first main optical axis and the second main optical axis. At this time, the virtual object points 12 of the first convergence point 10 and the second convergence point 11 overlap. Then, the first pyramid 4 and the second pyramid 5 are respectively moved leftwards and upwards by the same distance, and virtual object points 12 of the first convergence point 10 and the second convergence point 11 are positioned on the front focal plane of the rear lens 7 and are positioned symmetrically on two sides of the main optical axis. The light emitted by the first convergence point 10 is emitted out through a beam splitter 6 and a rear lens 7 to form parallel light beams; similarly, the light emitted by the second convergence point 11 also forms a parallel light beam to exit through the beam splitter 6 and the rear lens 7. At this time, two parallel light beams having a certain angle form interference fringes at an area array detector 9 (a CCD may be used) through a rear lens 7, wherein the area array detector 9 is located on a rear focal plane of the rear lens 7.
Referring to fig. 2, the first point 13 and the second point 14 are the front focus and the back focus of the rear lens 7, respectively, the lateral dashed line is the front focal plane, and the lateral solid line below the rear lens 7 is the back focal plane. The third point 17 and the fourth point 18 are the intersection points of the light ray and the back focal plane as shown in fig. 2, and the distance from the second point 14 to the fourth point 18 is equal to the distance from the second point 14 to the third point 17, the first wavefront 15 and the second wavefront 16 are two wavefronts of the parallel light beam formed by the converging point 10 passing through the back lens 7, and the third point 17 and the fourth point 18 are respectively located on the first wavefront 15 and the second wavefront 16.
Referring to fig. 2, the distance between the convergence point 10 and the virtual object point 12 is referred to as the shearing distanceThe method comprises the steps of carrying out a first treatment on the surface of the The included angle between the connecting line of the virtual object point 12 and the center of the rear lens and the second main optical axis is marked as +.>From shearing distance->And focal length determination of the rear lens 7; the distance between the second spot 14 and the third spot 17 is denoted +.>Is the arbitrary position coordinates of the detector. The first convergence point 10 and the second convergence point 11 represent the positions of the convergence coherent light source points. The virtual object point 12 and the convergence point two 11 are symmetrical to the beam splitter 6.
Referring to fig. 1 and 2, the principles of the present invention require an optical path differenceCoordinates of any position with the detector->Is a linear relationship. When two pyramids are each moved +>The incident and the outgoing light of each pyramid will be separated +>I.e. when the pyramids are moved by the same distance +.>Time shear distance->. Arbitrary position coordinates of detector->The optical path difference is->WhileFinal optical path difference and arbitrary position coordinates +.>The relation of->Wherein->Focal length for the rear lens 7. Maximum optical path difference variation: />Wherein->In order to form an included angle between the connecting line of the virtual object point 12 of the second convergence point 11 and the center of the rear lens 7 and the second main optical axis, N is the number of pixels in the transverse direction on the area array detector 9, and s is the pixel interval (size).
The information listing several key parameters in the present invention is as follows:
spectral resolution:；
for wavelengthMaximum interference order: />；
Maximum spatial frequency:；
sampling frequency of detector:；
sampling interval:；
pixel spacing:；
the key condition that the optical path difference and the coordinate position of the detector are in linear relation is that the equal interval sampling is satisfied. The interferogram light intensity expression is as follows:wherein->Representing beam->A spectral density function representing the light intensity, since only +.>It is practical and therefore the integral lower bound here is 0, and it can be seen that the spectral curve and the interferogram curve are a pair of fourier transform pairs. Finally through the formulaObtaining a spectral curve of the light to be measured, wherein +.>The position coordinates on the area array detector corresponding to the maximum optical path difference.
Referring to fig. 1, in the system resolution determination process, a laser with a certain fixed wavelength is used to perform shearing distance correction to determine the current shearing distance and the achievable resolution, and the correction method can be applied to monochromatic light incidence with any determined wavelength.
Referring to fig. 1 and 2, the conventional slit is omitted to realize virtual-to-actual conversion of the coherent light source point (i.e., the converging point two 11 is converted into the virtual object point 12), which has the advantages that the luminous flux of the light 1 to be measured entering the system is increased and the measurement is more convenient, the weak light signal can be measured under the condition of no cylindrical lens 8, the measurement technique and the complexity in the measurement of the system are greatly simplified, and the cylindrical lens 8 can be increased to compress interference fringes to complete the spectrum measurement when the weak light signal is measured.
When the interference data is used for recovering the spectrum, the interference image is acquired for a plurality of times, and the spectrum data after recovery is subjected to the averaging processing of the acquisition times, so that the electronic noise and the system micro vibration error are reduced to a lower level.
Compared with the common restoration process, the CZT conversion can realize spectrum refinement on the premise of not changing the maximum optical path difference, and solves the problem of larger spectrum error caused by lower spectrum resolution of the Fast Fourier Transform (FFT). The application of the method can more meet the visualization of the peak value details of the spectrum data, and the accuracy of the spectrum calibration can be improved.
In this embodiment, the method of the present invention is specifically implemented as follows: after the light 1 to be measured, which is led in by the incident optical fiber, is collimated by the collimating lens 2, the light is converged by the front lens 3 in front of the beam splitter 6, and the incident light is converged at the focal point (namely the converging point I10 and the converging point II 11) of the front lens 3. The front lens 3 with the focal length of 50mm is selected, two converging points are respectively positioned on the upper side and the right side of the beam splitter, namely, light rays are converged after passing through the beam splitter 6 (beam splitting ratio is 1:1), when the light rays are emitted from the beam splitter 6, the light rays pass through a pyramid, tertiary reflection is carried out on the light rays in the pyramid, and the emitting direction is parallel and opposite to the incident direction.
If the pyramid vertex is placed on the corresponding principal optical axis, the split light rays are emergent in the same direction, the two light rays keep the same optical path difference, the light rays are not separated, and no interference condition exists. The transverse distance between the first convergence point 10 and the virtual object point 12 of the second convergence point 11 is called a shearing distance, and the first pyramid 4 moves to the left side of the second main optical axis and the second pyramid 5 moves to the upper side of the first main optical axis. As shown in the ray trace of fig. 1, the incident pyramid rays will exit in the same direction, and after passing through the beam splitter 6 and the rear lens 7, two parallel rays with a certain included angle are formed. According to the model ray trace, when the pyramid one 4 and the pyramid two 5 move by the same distance, the transverse shearing distance is four times of the distance of the moving pyramid, namely, when the moving distance is 1mm, the shearing distance is 4mm. At this time, the two coherent light beams will pass through the rear lens 7, and the virtual object points 12 corresponding to the first convergence point 10 and the second convergence point 11 must be located on the front focal plane of the rear lens 7, as shown in fig. 2. When the two pyramids move by the same distance, the first convergence point 10 and the second convergence point 11 are positioned at symmetrical positions of the second main optical axis. Through the convergence of the rear lens 7, the two coherent light beams will interfere at the rear focal plane of the rear lens 7, and the optical path difference of each coherent light beam and any position coordinate on the area array detector 9 are linearly distributed. When the invention is used for measuring the multi-color light, two coherent lights can be compressed through the cylindrical lens 8, a line with light and shade alternation is displayed on the area array detector 9 after the compression, and the brightness on a line with light and shade stripes is compressed on one line at the moment, so that the invention has an important function for improving the intensity of weak light signal measurement. At this time, the interference modulation information received by the area array detector 9 is sent to a fourier transform system (a computer cooperates with corresponding computing software) in a picture form, and the measured interference information is subjected to fitting, smoothing, apodization and other operations, so that the extraction of the measured light information is finally realized, and the whole spectrum measurement work is completed. Theoretically, when the number N of pixels is 5472, the size s of the pixels is2.4 μm rear lensAt 75mm, the maximum shearing distance is 6.25mm, and the spectral resolution can reach 9.137cm -1 . When the data in the maximum interference range is completely detected, the ideal maximum resolution can reach 6.266cm -1 。
The present invention has been described above by way of example, but the present invention is not limited to the above-described embodiments, and any modifications or variations based on the present invention fall within the scope of the present invention.
Claims (10)
1. A high-throughput high-resolution static fourier transform spectroscopy method, comprising the steps of:
step S1: introducing light (1) to be measured into a static Fourier transform spectrum measurement system through a collimating lens (2);
step S2: the output interference fringes of the static Fourier transform spectrum measurement system are led out to an area array detector (9);
step S3: the image processing system is used for guiding the picture obtained by the area array detector (9) into the Fourier transform system;
step S4: and calculating target spectrogram information through Fourier transformation.
2. A high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 1, wherein: the static Fourier transform spectrum measurement system comprises a front lens (3), a pyramid I (4), a pyramid II (5), a beam splitter (6), a rear lens (7) and an area array detector (9), wherein the collimating lens (2), the front lens (3) and the beam splitter (6) are sequentially arranged from left to right, the centers of the collimating lens (2), the front lens (3) and the beam splitter (6) are located on a primary optical axis I, the pyramid I (4) and the pyramid II (5) are respectively located on the upper side and the right side of the beam splitter (6), the rear lens (7) is located on the lower side of the beam splitter (6), and the area array detector (9) is located on the lower side of the rear lens (7).
3. A high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 2, wherein: the optical fiber lens further comprises a cylindrical lens (8), wherein the cylindrical lens (8) is positioned between the rear lens (7) and the area array detector (9), and the centers of the beam splitter (6), the rear lens (7), the cylindrical lens (8) and the area array detector (9) are all positioned on the second main optical axis.
4. A high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 2, wherein: the pyramid I (4) moves relative to the beam splitting mirror (6) in the left-right direction, and the pyramid II (5) moves relative to the beam splitting mirror (6) in the up-down direction.
5. A high-throughput high-resolution static fourier transform spectrometry method according to any of claims 2-4, wherein step S2 comprises the steps of:
step S21: the light to be detected (1) is collimated through the collimating lens (2) to obtain parallel light, the parallel light enters the front lens (3) to be converged, and the converged light enters the first pyramid (4) and the second pyramid (5) after being split by the beam splitter (6) and forms a converging point I (10) and a converging point II (11) on the lower side of the first pyramid (4) and the left side of the second pyramid (5) respectively;
step S22: carrying out ray tracing on two beams of light split by a beam splitter (6), moving a pyramid I (4) in the left-right direction and a pyramid II (5) in the up-down direction until a converging point I (10) of the light after passing through the pyramid I (4) coincides with a virtual object point (12) corresponding to a converging point II (11) of the light after passing through the pyramid II (5);
step S23: moving the first pyramid (4) to the left side of the second main optical axis and the second pyramid (5) to the upper side of the first main optical axis, wherein the distance of the leftward movement of the first pyramid (4) and the distance of the upward movement of the second pyramid (5) are respectivelyAt the moment, light emitted by the first convergence point (10) and the second convergence point (11) passes through the beam splitter (6) and the rear lens (7) to form two parallel light beams with a certain included angle, and the two parallel light beams are projected to the area array detector (9).
6. The high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 5, wherein: the converging point I (10) converged by the front lens (3) is located between the pyramid I (4) and the beam splitter (6), and the converging point II (11) converged by the front lens (3) is located between the pyramid II (5) and the beam splitter (6).
7. A high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 2, wherein: the front lens (3) plays a role in converging, the rear lens (7) plays a role in collimating to generate two parallel light beams with a certain included angle, the transmission and reflection beam splitting ratio of the beam splitting lens (6) is 1:1, and the beam splitting lens (6) forms an included angle of 45 degrees with a main optical axis.
8. The high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 1, wherein the step S3 comprises the steps of:
step S31: the area array detector (9) acquires a two-dimensional picture comprising interference fringes;
step S32: and (3) intercepting the two-dimensional picture, respectively averaging the columns in the two-dimensional picture, and replacing column values with the obtained average value.
9. The method of high-throughput high-resolution static fourier transform spectroscopy as recited in claim 1, wherein step S4 comprises:
when two pyramids each moveEach pyramidIs divided into incident and emergent light>I.e. when the pyramids are moved by the same distance +.>Time shear distance->；
Arbitrary position coordinates of area array detector (9)The optical path difference is->And->Final optical path difference and arbitrary position coordinates +.>The relation of->Wherein->Focal length of the rear lens;
maximum optical path difference variation:wherein->An included angle between a connecting line of a virtual object point (12) of the second convergence point (11) and the center of the rear lens (7) and the second main optical axis is formed, N is the number of pixels in the transverse direction on the detector, and s is the pixel spacing;
the information listing several key parameters in the present invention is as follows:
spectral resolution:；
for wavelengthMaximum interference order: /> ；
Maximum spatial frequency:；
sampling frequency of detector:；
sampling interval:；
pixel spacing:；
the interferogram light intensity expression is as follows:wherein->Representing beam->A spectral density function representing light intensity, the spectral curve and the interferogram curve being a pair of fourier transform pairs;
finally through the formulaObtaining a spectral curve of the light (1) to be measured, whereinThe position coordinates on the area array detector corresponding to the maximum optical path difference.
10. The high-throughput high-resolution static fourier transform spectroscopy method as recited in claim 5, wherein: further comprising a step S24, said step S24 being located after step S23; the step S24: a fixed wavelength laser is used for shear-distance correction to determine the current shear-distance size and the resolution that can be achieved.
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