Video imaging spectrometer and optical system

Abstract

The utility model relates to a video imaging spectrometer and an optical system. The video imaging spectrometer comprises a first convergent lens; the collimating lens and the first convergent lens are coaxially arranged at an interval; the high-speed galvanometer, the first convergent lens and the collimating lens are arranged at intervals along the same straight line; the dispersion type imaging spectrometer is arranged on one side of the high-speed galvanometer and corresponds to the high-speed galvanometer in position; and the detector is arranged at the output end of the dispersion type imaging spectrometer. According to the video imaging spectrometer, the imaging mode that strip imaging is combined with low-speed scanning of an existing spectrometer is changed, a traditional large-size scanning mirror is changed into the high-speed galvanometer, a strip type linear field of view is broadened into an area array field of view through back-and-forth scanning of the high-speed galvanometer, and due to the fact that the high-speed galvanometer is located in the middle of an imaging light path, the imaging efficiency is greatly improved. Therefore, the size can be reduced, the scanning vibration frequency is improved, high-frame-rate video imaging can be realized, and the real-time performance of hyperspectral imaging is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of spectrometers, in particular to a video imaging spectrometer and an optical system. Background Art

[0002] Hyperspectral imaging spectrometers can obtain both the image information and spectral information of a target simultaneously, and are widely used in observation systems such as aircraft and spacecraft. With the development of technology, hyperspectral imaging technology has gradually penetrated into civilian fields such as biomedicine, anti-counterfeiting identification of artworks, food safety monitoring, disease control and treatment, etc., and has obtained more and more extensive research and application.

[0003] Spectral imaging technology is divided into several types in principle. Among them, the dispersive imaging spectrometer is the earliest proposed and practical imaging spectrometer, which has the advantages of simple principle and easy implementation. However, for the dispersive imaging spectrometer, each spectral imaging is for one ground object, and the entire field of view can be seen only after a set of spectral imaging processes are completed, and the field of view is selected, which greatly increases the time for imaging area selection and reduces the efficiency of the imaging spectrometer system.

[0004] Currently, the area array spectral imaging of the imaging spectrometer is mostly realized by setting a turntable or a swing mirror at the front of the spectrometer to improve the working efficiency of the spectrometer; however, the imaging method of turntable scanning realized by the turntable generally can only achieve low-frame-rate imaging of strips, with poor real-time performance; and the scanning mirror has problems such as too large size, low scanning frequency, and inability to achieve high-frame-rate video-level hyperspectral imaging. Content of the Utility Model

[0005] Therefore, the technical problem to be solved by the utility model is to overcome the problem that in the prior art, the area array spectral imaging of the imaging spectrometer is mostly realized by setting a turntable or a swing mirror at the front of the spectrometer to improve the working efficiency of the spectrometer; however, the imaging method of turntable scanning realized by the turntable generally can only achieve low-frame-rate imaging of strips, with poor real-time performance; and the scanning mirror has problems such as too large size, low scanning frequency, and inability to achieve high-frame-rate video-level hyperspectral imaging.

[0006] To solve the above technical problems, the utility model provides a video imaging spectrometer, including,

[0007] A first converging lens;

[0008] A collimating lens, the collimating lens is coaxially arranged with and spaced from the first converging lens;

[0009] A high-speed galvanometer, the high-speed galvanometer is spaced along the same straight line from the first converging lens and the collimating lens, and the high-speed galvanometer is located on the side of the collimating lens away from the first converging lens;

[0010] A dispersive imaging spectrometer is disposed on one side of the high-speed galvanometer, and the input end of the dispersive imaging spectrometer corresponds to the position of the high-speed galvanometer.

[0011] A detector is disposed at the output end of the dispersive imaging spectrometer.

[0012] In an embodiment of the present utility model, a second converging lens is further included, and the second converging lens is disposed between the input end of the dispersive imaging spectrometer and the high-speed galvanometer.

[0013] In an embodiment of the present utility model, the input end of the dispersive imaging spectrometer corresponds to the focal plane position of the second converging lens.

[0014] In an embodiment of the present utility model, a mounting base is further included, and the first converging lens, the collimating lens, the high-speed galvanometer, the second converging lens, the dispersive imaging spectrometer and the detector are respectively disposed on the mounting base.

[0015] In an embodiment of the present utility model, the detector is a area array detector.

[0016] In an embodiment of the present utility model, a galvanometer controller is further included, and the galvanometer controller is connected to the high-speed galvanometer.

[0017] In an embodiment of the present utility model, the working wavelength range of the dispersive imaging spectrometer is within 400nm - 1000nm.

[0018] In an embodiment of the present utility model, the working wavelength range of the dispersive imaging spectrometer is within 400nm - 2500nm, 3000nm - 5000nm or 8000nm - 12500nm.

[0019] An optical system includes the imaging spectrometer described in any one of the above.

[0020] The above technical solution of the present utility model has the following advantages compared with the prior art:

[0021] A video imaging spectrometer and an optical system according to the present utility model include a first converging lens, a collimating lens, a high-speed galvanometer, a dispersive imaging spectrometer, and a detector; the collimating lens is coaxially arranged with the first converging lens and spaced apart from each other; the high-speed galvanometer is spaced apart from the first converging lens and the collimating lens along the same straight line, and the high-speed galvanometer is located on the side of the collimating lens away from the first converging lens; the dispersive imaging spectrometer is arranged on one side of the high-speed galvanometer, and the input end of the dispersive imaging spectrometer corresponds to the position of the high-speed galvanometer; the detector is arranged at the output end of the dispersive imaging spectrometer. A video imaging spectrometer of the present utility model changes the existing imaging method of combining strip imaging and low-speed scanning of the dispersive imaging spectrometer. By innovating the composition and structure of the imaging spectrometer, the traditional large-size scanning mirror is changed to an intermediate parallel optical path scanning mirror (i.e., a high-speed galvanometer). The strip-shaped line array field of view of the imaging spectrometer is widened into a matrix field of view by the back-and-forth scanning of the high-speed galvanometer. And because the high-speed galvanometer is located in the middle position of the imaging optical path, the volume of the high-speed galvanometer can be reduced, which is beneficial to increasing the reciprocating scanning vibration frequency of the scanning mirror, enabling high-frame-rate video imaging of the imager, greatly improving the real-time performance of hyperspectral imaging, and expanding the application range of the original imaging spectrometer from only being applicable to low-speed and slow imaging to high-speed imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to make the content of the present utility model easier to be clearly understood, the following further details the present utility model according to the specific embodiments of the present utility model in conjunction with the drawings, where

[0023] Figure 1 is a schematic diagram of the overall structure of the video imaging spectrometer of the preferred embodiment of the present utility model.

[0024] Description of the reference numerals in the drawings: 1. First converging lens; 2. Collimating lens; 3. High-speed galvanometer; 4. Dispersive imaging spectrometer; 5. Detector; 6. Second converging lens; 7. Galvanometer controller. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following further describes the present utility model in conjunction with the drawings and specific embodiments, so that those skilled in the art can better understand the present utility model and be able to implement it, but the embodiments cited do not limit the present utility model.

[0026] Embodiment 1

[0027] Referring to Figure 1 as shown, a video imaging spectrometer of the present utility model includes

[0028] a first converging lens 1;

[0029] A collimating lens 2, wherein the collimating lens 2 and the first converging lens 1 are coaxially arranged and spaced from each other;

[0030] A high-speed galvanometer 3, wherein the high-speed galvanometer 3, the first converging lens 1 and the collimating lens 2 are arranged along the same straight line and spaced apart from each other, and the high-speed galvanometer 3 is located on a side of the collimating lens 2 away from the first converging lens 1;

[0031] A dispersive imaging spectrometer 4, which is disposed on one side of the high-speed galvanometer 3, and an input end of the dispersive imaging spectrometer 4 corresponds to a position of the high-speed galvanometer 3;

[0032] The detector 5 is arranged at the output end of the dispersive imaging spectrometer 4 .

[0033] Specifically, the first converging lens 1 is used to converge the light from the target object, and the collimating lens 2 is used to collimate the converged light into parallel light (it can be imagined that the collimating lens 2 and the first converging lens 1 are combined with each other to compress the aperture of the entire optical mechanism); the high-speed galvanometer 3 is located in the parallel light path, and the high-speed galvanometer 3 can perform reciprocating, high-speed scanning and swinging within a certain range. There is a linear region for a certain period of time during the swinging process of the high-speed galvanometer 3, and the field of view scanning of the imaging spectrometer can be completed in the linear region (the video output frame rate of the video imaging spectrometer is equal to the frequency of the high-speed galvanometer 3); the second converging lens 6 can converge the light path after passing through the high-speed galvanometer 3 again, so that the light path converges at the focal plane position of the dispersive imaging spectrometer 4.

[0034] The utility model discloses a video imaging spectrometer, which changes the existing imaging mode of strip imaging combined with low-speed scanning of the dispersion-type imaging spectrometer 4, and innovates the composition and structure of the imaging spectrometer, thereby changing the traditional large-size scanning mirror into an intermediate parallel light path scanning mirror (i.e., the high-speed galvanometer 3), and widens the strip-type linear array field of view of the imaging spectrometer into a planar array field of view through the back-and-forth scanning of the high-speed galvanometer 3. In addition, since the high-speed galvanometer 3 is located in the middle of the imaging light path, the volume of the high-speed galvanometer 3 can be reduced, which is beneficial to increase the reciprocating scanning vibration frequency of the scanning mirror, and can realize high-frame rate video imaging of the imaging instrument, greatly improve the real-time performance of hyperspectral imaging, and expand the application range of the original imaging spectrometer, which is only suitable for low-speed and slow imaging, to the application range of high-speed imaging.

[0035] Furthermore, a second converging lens 6 is included, which is arranged between the input end of the dispersive imaging spectrometer 4 and the high-speed galvanometer 3. The second converging lens 6 can perform secondary converging on the light path after passing through the high-speed galvanometer 3, so that the light path converges at the focal plane position of the dispersive imaging spectrometer 4.

[0036] Furthermore, the input end of the dispersive imaging spectrometer 4 corresponds to the focal plane position of the second converging lens 6. The dispersive imaging spectrometer 4 is a device that performs spectral imaging by means of a grating, a prism, or a prism-grating-prism, etc. Its slit is located at the focal plane position of the second converging lens 6.

[0037] Furthermore, the detector 5 is a high-frequency area array detector, and its frame rate is related to the frame rate of the output video, the number of spectral bands, and the imaging field of view.

[0038] Furthermore, it further includes a galvanometer controller 7. The galvanometer controller 7 is connected to the high-speed galvanometer 3, and the galvanometer controller 7 is used to drive and control the high-speed galvanometer 3.

[0039] Furthermore, the working wavelength band of the dispersive imaging spectrometer 4 is in the range of 400 nm - 1000 nm.

[0040] Furthermore, the working wavelength band of the dispersive imaging spectrometer 4 is in the range of 400 nm - 2500 nm, 3000 nm - 5000 nm, or 8000 nm - 12500 nm. The dispersive imaging spectrometer 4 can be selected according to different usage requirements.

[0041] Furthermore, it further includes a mounting base. The first converging lens 1, the collimating lens 2, the high-speed galvanometer 3, the second converging lens 6, the dispersive imaging spectrometer 4, the detector 5, and the galvanometer controller 7 are respectively connected to the mounting base. More preferably, multiple mounting bases capable of adjusting positions in the X-axis, Y-axis, and Z-axis directions can be provided on the mounting base, and each component of the video imaging spectrometer can be respectively arranged on one mounting base, which is convenient for the staff to adjust the relative positions between the components.

[0042] Embodiment 2

[0043] The present utility model also discloses an optical system, including the imaging spectrometer as in Embodiment 1.

[0044] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present utility model.

Claims

1. A video imaging spectrometer, characterized in that: include: a first converging lens; a collimating lens, the collimating lens and the first converging lens are coaxially arranged and spaced from each other; A high-speed galvanometer, wherein the high-speed galvanometer, the first converging lens and the collimating lens are arranged along the same straight line at intervals, and the high-speed galvanometer is located on a side of the collimating lens away from the first converging lens; A dispersive imaging spectrometer, wherein the dispersive imaging spectrometer is arranged on one side of the high-speed galvanometer, and an input end of the dispersive imaging spectrometer corresponds to a position of the high-speed galvanometer; A detector is arranged at the output end of the dispersive imaging spectrometer.

2. The imaging spectrometer according to claim 1, characterized in that: It also includes a second converging lens, which is arranged between the input end of the dispersive imaging spectrometer and the high-speed galvanometer.

3. The imaging spectrometer according to claim 2, characterized in that: The input end of the dispersive imaging spectrometer corresponds to the focal plane position of the second converging lens.

4. The imaging spectrometer according to claim 2, characterized in that: It also includes a mounting seat, on which the first converging lens, the collimating lens, the high-speed galvanometer, the second converging lens, the dispersive imaging spectrometer and the detector are respectively arranged.

5. The imaging spectrometer according to claim 1, characterized in that: The detector is a planar array detector.

6. The imaging spectrometer according to claim 1, characterized in that: It also includes a galvanometer controller, which is connected to the high-speed galvanometer.

7. The imaging spectrometer according to claim 1, characterized in that: The working band of the dispersive imaging spectrometer is within the range of 400nm-1000nm.

8. The imaging spectrometer according to claim 1, characterized in that: The operating band of the dispersive imaging spectrometer is within the range of 400nm-2500nm, 3000nm-5000nm or 8000nm-12500nm.

9. An optical system, characterized in that: Comprising an imaging spectrometer as described in any one of claims 1-8.

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