Prism dispersion type spectrometer and spatial attitude adjustment device and method thereof

Abstract

The invention relates to a prism dispersion type spectrometer and a spatial attitude adjustment device and method thereof, belongs to the technical field of optical instrument adjustment, and solves the technical problem of low spatial attitude adjustment precision of a hyperspectral imaging system. The spatial attitude adjustment method of the prism dispersion type spectrometer comprises the steps of curved prism positioning, reflector positioning and coaxial lens group positioning. The space attitude adjusting device comprises an air floating platform, an interferometer, an optical theodolite, a flexible joint arm, a laser tracker, a shearing table, a five-dimensional adjusting frame and a target ball. The prism dispersion type spectrometer optical system comprises a coaxial lens group, a curved prism and a reflector which are sequentially arranged along an optical path. The prism dispersion type spectrometer comprises the prism dispersion type spectrometer optical system. The invention is used for a hyperspectral imaging system.

Description

Technical Field

[0001] The invention belongs to the technical field of optical instrument adjustment, and in particular relates to a prism dispersion spectrometer and a spatial posture adjustment device and method thereof. Background Art

[0002] With the rapid development of modern optical technology, the application of high-precision spatial attitude adjustment in optical systems has become increasingly important. Especially in prism dispersion spectrometers, the curved prism is a key optical element, and even a slight change in its spatial attitude may have a significant impact on the imaging quality. Therefore, studying a method that can achieve high-precision spatial attitude adjustment of prism dispersion is of great significance for improving the performance of prism dispersion spectrometers. Traditional spatial attitude adjustment methods mainly rely on mechanical adjustment devices. Although this method can achieve a certain degree of adjustment, it is often difficult to meet the needs of high-precision adjustment due to the limitations of mechanical accuracy and stability. In addition, traditional adjustment methods usually require manual operation, which is not only inefficient, but also difficult to ensure the accuracy and consistency of the adjustment. In recent years, with the continuous advancement of high-precision measurement technology, such as optical theodolite measurement technology, laser tracker network measurement and flexible joint arm measurement, interferometer measurement technology, etc., new solutions have been provided for spatial attitude adjustment. These technologies can achieve precise control of the spatial attitude of the target object through high-precision measurement and positioning. Summary of the invention

[0003] In order to overcome the shortcoming of low precision in spatial attitude adjustment of a hyperspectral imaging system, the present invention proposes a prism dispersion spectrometer and a spatial attitude adjustment device and method thereof.

[0004] The technical solution adopted by the present invention to solve the technical problem is:

[0005] A method for adjusting the spatial attitude of a prism dispersion spectrometer comprises the following steps:

[0006] Step S1: Positioning the curved prism

[0007] The first step is to establish a spatial coordinate system

[0008] The prism dispersion spectrometer to be installed and adjusted is placed on an air-floating platform supported by a shearing table. An optical theodolite is used to adjust the prism dispersion spectrometer to be installed and adjusted to be horizontal. The mechanical reference is taken as the X and Y planes, the bracket mounting surface is taken as the Z plane, and the flexible joint arm is used to collect points for fitting to establish a spatial coordinate system.

[0009] Step 2: Install the curved prism lens bracket

[0010] The flexible joint arm is used to adjust the spatial position of the curved prism lens bracket so that the spatial position of the curved prism lens bracket reaches a theoretical position.

[0011] Step 3: Install the interferometer

[0012] Install the interferometer; install and remove the curved prism; use a five-dimensional adjustment frame and laser tracker to make the curved prism lens bracket, interferometer, and target ball center form a straight line with the optical axis centered.

[0013] Step 4: Install the curved prism

[0014] Install the curved prism to reflect the convex image point of the curved prism; adjust the image point of the curved prism, rotate the curved prism to return the image point, and adjust it to coincide with the center of the interferometer image point; adjust the phase position of the curved prism to the theoretical position.

[0015] Step S2, reflector positioning

[0016] The first step is to install the reflector bracket

[0017] The space coordinate system of the reflector bracket is established by sampling points through the flexible joint arm, and the reflector bracket is fitted into the mounting end surface of the reflector bracket. The reflector bracket is installed according to the position of the mounting end surface of the reflector bracket.

[0018] Step 2: Fine-tune the reflector bracket

[0019] Measure the angle between the reflector mounting end face and the X, Y, and Z planes, and adjust the pitch angle and azimuth angle of the reflector bracket so that the angle is within the error range with the theoretical angle.

[0020] Step S3, coaxial mirror group positioning

[0021] The first step is to install the coaxial mirror bracket

[0022] Use the flexible joint arm to collect points, fit them into the coaxial mirror group installation end face, and install the coaxial mirror group bracket according to the position of the coaxial mirror group installation end face.

[0023] Step 2: Fine-tune the coaxial mirror bracket

[0024] Measure the angles between the mounting end face of the coaxial mirror group and the X, Y, and Z planes, and adjust the pitch angle and azimuth angle of the coaxial mirror group bracket to make their angles within the theoretical error range.

[0025] The above-mentioned spatial posture adjustment method, the third step of step S1, installing the interferometer, further comprises:

[0026] Install the interferometer so that the prism-adjustable dispersion spectrometer to be installed is located between the interferometer and the target sphere.

[0027] Install the curved prism on the lens bracket, adjust the convex image point and the focal distance of the interferometer standard lens, so that the interferometer receives clear interference fringes, and locate the reference position of the dispersion spectrometer to be installed with the prism.

[0028] A laser tracker is used to establish the parts coordinate system of the dispersive spectrometer with adjustable prisms to be installed according to the reference position.

[0029] According to the reference position of the dispersion spectrometer to be installed with the adjustable prism, the spatial position of the center point of the convex sphere is located, the target sphere is placed on the five-dimensional adjustment frame, and the position of the target sphere is adjusted to the theoretical coordinates in space.

[0030] Remove the curved prism, the interferometer laser spot passes through the center of the lens bracket, and the focus of the standard spherical mirror converges on the surface of the target ball, that is, the optical axes are consistent.

[0031] According to the position of the optical axis, adjust the posture of the base plate so that the curved prism lens holder, interferometer and target ball center are in a straight line, that is, the optical axis is centered.

[0032] In the above-mentioned spatial posture adjustment method, the focal length of the interferometer standard lens is obtained by calculating the F number of the interferometer standard lens according to the curvature radius of the convex surface of the curved prism.

[0033] In the above-mentioned spatial posture adjustment method, in the step S1 of positioning the curved prism, the phase position of the curved prism is adjusted to the theoretical position, that is, the pitch and azimuth position relationship of the curved prism is adjusted so that its interference fringes are zero fringes.

[0034] In the above-mentioned spatial posture adjustment method, in the step S2 of reflector positioning, the pitch angle between the reflector bracket and the reference plane is adjusted by grinding the trimming pad at the bottom of the reflector, and the azimuth angle between the reflector bracket and the reference plane is adjusted by micro-rotating the reflector bracket.

[0035] In the above-mentioned spatial posture adjustment method, in step S3, during the coaxial mirror group positioning, the pitch angle between the coaxial mirror group bracket and the reference plane is adjusted by grinding the trimming pad at the bottom of the reflector, and the azimuth angle between the coaxial mirror group bracket and the reference plane is adjusted by micro-rotating the reflector bracket.

[0036] A space attitude adjustment device for a prism dispersion spectrometer comprises an air floating platform, an interferometer, an optical theodolite, a flexible joint arm, a laser tracker, a shearing table, a five-dimensional adjustment frame and a target ball.

[0037] The prism dispersive spectrometer to be installed is located on an air-floating platform, which is supported by a shearing platform. The air-floating platform, the shearing platform and the optical theodolite are used to adjust the level of the prism dispersive spectrometer to be installed.

[0038] The interferometer is located at a position of the curved prism support relative to the convex surface and is used for positioning the curved prism lens support.

[0039] The target ball is located on a five-dimensional adjustment frame, and the five-dimensional adjustment frame is used to adjust the target ball to be located at a theoretical spatial coordinate.

[0040] The laser tracker is used to establish a part coordinate system according to the reference of the dispersion spectrometer of the prism to be installed.

[0041] The flexible joint arm is used to collect points and establish a spatial coordinate system.

[0042] A prism dispersion spectrometer optical system comprises a coaxial lens group, a curved prism and a reflector which are sequentially arranged along an optical path.

[0043] The coaxial lens group, the curved prism and the reflector are supported by a coaxial lens group bracket, a curved prism lens bracket and a reflector bracket respectively.

[0044] The coaxial lens group includes lens 1, lens 2, lens 3, lens 4 and lens 5 which are sequentially arranged along the optical path.

[0045] A prism dispersion spectrometer comprises the prism dispersion spectrometer optical system.

[0046] The beneficial effects of the present invention are:

[0047] A spatial attitude adjustment device for a prism dispersion spectrometer realizes data quantification through precise benchmark measurement, has high positioning accuracy and strong operability.

[0048] A spatial posture adjustment method for a prism dispersion spectrometer uses a laser tracker with an accuracy of 0.01mm, a flexible joint arm with an accuracy of 0.02mm, and a self-collimating optical theodolite with an accuracy of 0.5" to perform high-precision spatial posture positioning and precision measurement of each optical component in an off-axis reentrant optical system, with a comprehensive measurement accuracy better than 0.03mm.

[0049] A spatial posture adjustment method for a prism dispersion spectrometer uses a flexible joint arm to establish a unified spatial coordinate system with a mechanical reference, and obtains quantitative data for spatial posture measurement by sampling and fitting the mounting end faces of each mirror group, thereby reducing the difficulty of assembly and integration.

[0050] A spatial attitude adjustment method for a prism dispersion spectrometer can, firstly, realize high-precision spatial attitude measurement and adjustment of a lens holder to meet the high requirements of a hyperspectral imaging system for imaging quality; secondly, realize quantitative data adjustment to improve adjustment efficiency and accuracy; and thirdly, can adapt to the needs of different optical systems and has good versatility and scalability. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a schematic diagram of the structure of the optical system of the prism dispersion spectrometer according to an embodiment of the present invention.

[0052] Markings in the figure: 1. curved prism, 2. reflector, 3. coaxial mirror group. DETAILED DESCRIPTION

[0053] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] Embodiment 1

[0055] The present invention proposes a high-precision spatial attitude phase adjustment method based on a prism dispersion spectrometer. Based on a prism dispersion hyperspectral imaging system and high-precision measurement technology, the method utilizes high-precision instrument equipment for network measurement, and realizes precise adjustment of the spatial attitude of a curved prism by quantifying relevant data. Specifically, the present invention uses an optical system as the core, combines high-precision measurement technologies such as laser tracker measurement technology, theodolite measurement technology, and interferometer measurement technology, and constructs a high-precision measurement network. By collecting and analyzing the spatial position information of the lens in different attitudes, combined with the high-precision spatial positioning information provided by the measurement network, it is possible to achieve precise measurement and adjustment of the spatial attitude of each lens in the optical system.

[0056] The optical path specifically constructed in the present invention includes devices such as the adjusted product component, the air floating platform, the interferometer, the theodolite, the flexible joint arm, the laser tracker, the shearing table, and the five-dimensional adjustment frame.

[0057] A spatial attitude adjustment method based on a prism dispersion spectrometer, wherein the optical system of the prism dispersion spectrometer is sequentially arranged along the optical path as follows: (lens one, lens two, lens three, lens four, lens five) coaxial lens group, curved prism, reflector (such as Figure 1 The specific method includes the following steps:

[0058] 1. Accurately position the curved prism;

[0059] 2. Place the product on an air-floating platform, supported by a shearing table, and use an optical theodolite to adjust it to ground level;

[0060] 3. With the mechanical reference as the X and Y planes, the bracket installation surface as the Z plane, and the flexible joint arm sampling points to fit and establish a spatial coordinate system;

[0061] 4. According to the optical system design, pre-plan the initial installation position of the visible curved prism;

[0062] 5. Install the curved prism lens bracket and use the flexible joint arm to adjust the spatial position of the curved prism lens mounting bracket to achieve the theoretical position deviation (based on the side of the product bottom plate);

[0063] 6. Place the interferometer in the curved prism frame relative to the convex surface;

[0064] 7. Select a suitable standard lens according to the curvature radius of the convex surface of the curved prism;

[0065] 8. Install the standard lens on the interferometer, determine the spatial position of the product according to the focal position of the standard lens, and place the product between the interferometer and the target sphere;

[0066] 9. Install the curved prism on the lens bracket, adjust the convex image point and the standard lens focal distance to ensure that the interferometer can receive clear interference fringes (0 fringes), and locate the front and rear distance of the product at this position;

[0067] 10. Establish the part coordinate system according to the product benchmark on the laser tracker;

[0068] 11. According to the product position reference, locate the spatial position of the convex sphere center point, place the target ball on the five-dimensional adjustment frame, and adjust the spatial posture position of the target ball to the theoretical spatial coordinates;

[0069] 12. Remove the curved prism, and the interferometer laser spot passes through the center of the lens bracket;

[0070] 13. The focus of the standard spherical mirror converges on the surface of the target ball to ensure that the optical axis is consistent;

[0071] 14. According to the position of the optical axis, adjust the spectrometer base plate again so that the curved prism lens bracket, interferometer, and target ball center are in a straight line and the optical axis is centered;

[0072] 15. Install the curved prism to reflect the convex image point of the curved prism, rotate the curved prism to adjust the image point of the curved prism, return the image point, and adjust it to coincide with the center of the interferometer image point;

[0073] 16. (By adjusting the pitch and azimuth position relationship of the curved prism, the interference fringes are adjusted to the best state, the 0 fringe is the best, and its phase direction is considered to coincide with the position of the back spherical center image point) It is considered that the phase position of the curved prism is adjusted to the theoretical position;

[0074] 17. Accurately position the reflector;

[0075] 18. According to the design requirements of the optical system, the space coordinate system is established by sampling points through the flexible joint arm;

[0076] 19. Install the reflector bracket according to the pre-planned reflector installation position, use the flexible joint arm to measure the reflector installation end surface, and fit the measurement points into a surface;

[0077] 20. Measure the angle between the reflector mounting end face and the X, Y, and Z reference planes, and adjust the pitch angle of the reflector bracket to ensure that it is within the error range with the theoretical angle;

[0078] 21. The pitch angle between the reflector bracket and the reference surface is adjusted by grinding the trimming pad at the bottom of the reflector, and the azimuth angle is adjusted by micro-rotating the reflector bracket;

[0079] 22. Accurately position the coaxial mirror group;

[0080] 23. Install the coaxial mirror bracket according to the pre-planned coaxial mirror position, use the flexible joint arm to measure the coaxial mirror installation end surface, and fit the measuring points into a surface;

[0081] 24. Measure the angle between the mounting end face of the coaxial mirror group and the X, Y, and Z reference planes, and adjust the pitch angle of the coaxial mirror group bracket to ensure that the angle is within the theoretical error range;

[0082] The pitch angle between the coaxial mirror assembly bracket and the reference plane is adjusted by grinding the trimming pad at the bottom of the reflector, and the azimuth angle is adjusted by micro-rotating the reflector bracket.

[0083] A spatial posture adjustment method for a prism dispersion spectrometer uses a laser tracker (accuracy 0.01mm), a flexible joint arm (accuracy 0.02mm), and a self-collimating optical theodolite (0.5") to perform high-precision spatial posture positioning and precision measurement of each optical component in an off-axis reentrant optical system, with a comprehensive measurement accuracy better than 0.03mm.

Claims

1. A method for adjusting the spatial attitude of a prism dispersion spectrometer, characterized in that: The following steps are involved: Step S1, curved prism positioning: The first step is to establish a spatial coordinate system: place the prism dispersion spectrometer to be installed and adjusted on an air-floating platform supported by a shearing table, and use an optical theodolite to adjust the prism dispersion spectrometer to be installed and adjusted to a horizontal level; take the mechanical reference as the X and Y planes, the bracket installation surface as the Z plane, and use the flexible joint arm to collect points for fitting to establish a spatial coordinate system; The second step is to install the curved prism lens bracket: use the flexible joint arm to adjust the spatial position of the curved prism lens bracket so that the spatial position of the curved prism lens bracket reaches the theoretical position; The third step is to install the interferometer: install the interferometer; install and remove the curved prism; use a five-dimensional adjustment frame and a laser tracker to make the curved prism lens bracket, the interferometer, and the target ball center in a straight line with the optical axis in the center; Step 4: Install the curved prism: Install the curved prism to reflect the convex image point of the curved prism; adjust the image point of the curved prism, rotate the curved prism to return the image point, and adjust it to coincide with the center of the interferometer image point; adjust the phase position of the curved prism to the theoretical position; Step S2, reflector positioning: The first step is to install the reflector bracket: use the flexible joint arm to collect points and establish the spatial coordinate system of the reflector bracket. Fitting the reflector bracket to form a mounting end face; installing the reflector bracket according to the position of the mounting end face of the reflector bracket; The second step is to fine-tune the reflector bracket: measure the angle between the reflector mounting end face and the X, Y, and Z planes, and adjust the pitch angle and azimuth angle of the reflector bracket so that the angle is within the error range with the theoretical angle; Step S3, coaxial mirror group positioning: The first step is to install the coaxial mirror bracket: use the flexible joint arm to collect points, fit them into the coaxial mirror installation end face, and install the coaxial mirror bracket according to the position of the coaxial mirror installation end face; The second step is to fine-tune the coaxial mirror bracket: measure the angle between the coaxial mirror mounting end face and the X, Y, and Z planes, and adjust the pitch angle and azimuth angle of the coaxial mirror bracket to make its angle within the theoretical error range.

2. The spatial posture adjustment method according to claim 1, characterized in that: The third step of step S1, installing the interferometer, further comprises: Install the interferometer so that the prism-adjustable dispersion spectrometer to be installed is located between the interferometer and the target sphere; Install the curved prism on the lens bracket, adjust the distance between the convex image point and the focal point of the interferometer standard lens, so that the interferometer receives clear interference fringes, and locate the reference position of the dispersion spectrometer to be installed with the prism; A laser tracker is used to establish the parts coordinate system of the prism dispersion spectrometer to be installed according to the reference position; According to the reference position of the dispersion spectrometer to be installed with the prism adjustment, locate the spatial position of the center point of the convex sphere, place the target sphere on the five-dimensional adjustment frame, and adjust the position of the target sphere to the theoretical spatial coordinates; Remove the curved prism, the interferometer laser spot passes through the center of the lens bracket, and the focus of the standard spherical mirror converges on the surface of the target ball, that is, the optical axes are consistent; According to the position of the optical axis, adjust the posture of the base plate so that the curved prism lens holder, the interferometer, and the center of the target ball are in a straight line, that is, the optical axis is centered.

3. The spatial posture adjustment method according to claim 2, characterized in that: The focal length of the interferometer standard lens is obtained by calculating the F number of the interferometer standard lens according to the curvature radius of the convex surface of the curved prism.

4. The spatial posture adjustment method according to claim 1, characterized in that: In the step S1 of positioning the curved prism, the phase position of the curved prism is adjusted to a theoretical position, that is, the pitch and azimuth position relationship of the curved prism is adjusted so that its interference fringes are zero fringes.

5. The spatial posture adjustment method according to claim 1, characterized in that: In the step S2 of positioning the reflector, the pitch angle between the reflector bracket and the reference plane is adjusted by grinding the trimming pad at the bottom of the reflector, and the azimuth angle between the reflector bracket and the reference plane is adjusted by micro-rotating the reflector bracket.

6. The spatial posture adjustment method according to claim 1, characterized in that: In the step S3, during the coaxial mirror group positioning, the pitch angle between the coaxial mirror group bracket and the reference plane is adjusted by grinding the trimming pad at the bottom of the reflector, and the azimuth angle between the coaxial mirror group bracket and the reference plane is adjusted by micro-rotating the reflector bracket.

7. A device for implementing any one of the methods of claims 1 to 6, characterized in that: Including air floating platform, interferometer, Optical theodolite, flexible joint arm, laser tracker, shearing table, five-dimensional adjustment frame, target ball; The prism dispersive spectrometer to be installed is located on an air-floating platform; the air-floating platform is supported by a shearing platform, and the air-floating platform, the shearing platform, and the optical theodolite are used to adjust the level of the prism dispersive spectrometer to be installed; The interferometer is located at a position of the curved prism support relative to the convex surface and is used for positioning the curved prism lens support; The target ball is located on a five-dimensional adjustment frame, and the five-dimensional adjustment frame is used to adjust the target ball to the theoretical coordinates of the space; The laser tracker is used to establish a part coordinate system according to the reference of the dispersive spectrometer with adjustable prism to be installed; The flexible joint arm is used to collect points and establish a spatial coordinate system.

8. A prism dispersion spectrometer optical system, characterized in that: It comprises a coaxial lens group (2), a curved prism (1), and a reflector (3) which are sequentially arranged along the optical path; The coaxial lens group (2), the curved prism (1), and the reflector (3) are supported by a coaxial lens group bracket, a curved prism lens bracket, and a reflector bracket, respectively; The coaxial lens group (2) comprises a lens 1, a lens 2, a lens 3, a lens 4 and a lens 5 which are arranged in sequence along the optical path.

9. A prism dispersion spectrometer, characterized in that: The invention comprises the prism dispersion spectrometer optical system as described in claim 8.

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