A high-precision imaging device high-low temperature optical axis stability testing device and method

Abstract

The application discloses a high-precision imaging device high-low temperature optical axis stability testing device and method, and is applied to the field of imaging device optical axis stability testing. The existing optical axis stability testing method has the problems of poor vibration isolation effect and prominent window refraction, thereby leading to low optical axis stability testing precision. The application improves the vibration isolation effect of the measured imaging device by means of the temperature box vibration isolation treatment and the turntable suitable for high-low temperature performance, improves the mechanical positioning precision by means of the three-dimensional high-precision rotation of the long-focus large-aperture self-collimation system, and replaces the traditional germanium glass window with the nitrogen-filled film window suitable for simulating the air environment to reduce the window refraction, so as to improve the optical axis stability testing precision of the system on the imaging device.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of imaging device optical axis stability test, and particularly relates to a high-precision imaging device high-low temperature optical axis stability test device and method. BACKGROUND

[0002] The environment in which the imaging device is actually used is complex, especially the change of environmental temperature has a series of influences on the equipment itself, the lens, the detector and the like, and in addition, the application of the thermal imager in the civil and military fields is continuously expanded, and the observation is gradually changed from the human eye observation to the machine observation, and the accuracy of the observation result directly influences the accuracy and reliability of the machine identification and aiming, and the optical axis stability suitable for different environments is particularly important in the observation.

[0003] Therefore, how to scientifically, objectively and accurately detect the optical axis stability of the thermal imager under different environmental temperatures has been a difficult problem in the test field.

[0004] The current domestic and foreign methods are all indirect measurement methods of rotating the measured device to measure the optical axis, and the optical axis stability test almost all follows this method, and the basic test principle of the method is that: first, the optical path of the system is calibrated by using an optical autocollimator and the like, then the measured device is placed in an environmental temperature test box and the system is started, different environmental temperatures are set, the optical axis change of the measured device in the environmental temperature test box with the change of the temperature is obtained by adjusting the rotary table, and the optical axis stability of the measured device is measured. The indirect test method of rotating the thermal imager has many problems that cannot be solved:

[0005] (1) In order to observe the target, a glass window is usually used, and there is obvious refraction and its own transfer function, and the real performance of the window of the measured device cannot be truly reflected.

[0006] (2) The workpiece, the rotary table and the like in the temperature box change with the change of the environmental temperature, and there is a slight deformation, which is fatal to the optical axis stability test, and the error directly exceeds the optical axis deviation of the measured device when the error is serious.

[0007] (3) The rotary table and the measured device are placed in the temperature box at the same time, and the large rotary table is used to rotate the temperature box, which can alleviate the influence caused by (1)

[0008] , but it also leads to that the vibration isolation of the temperature box is almost difficult to realize, and the vibration still causes a large system error, and the optical axis deviation of the measured device with the change of the temperature cannot be truly reflected. SUMMARY

[0009] In order to solve the above technical problems, the present application provides an accurate and reliable, general-purpose, high-precision imaging device optical axis stability test device and method.

[0010] The technical scheme of the present application is as follows: a high-precision imaging device high-low temperature optical axis stability testing device, comprising: a collimator system, an environmental temperature test box, a photoelectric autocollimator, an optical platform and a control processing computer; the collimator system, the environmental temperature test box and the photoelectric autocollimator are arranged on the optical platform; the collimator system, the environmental temperature test box, the measured device and the photoelectric autocollimator are connected with the control processing computer through cables;

[0011] The collimator system comprises: a collimator, a variable temperature target system and a three-dimensional adjustment displacement device; the variable temperature target system is used for providing a target at a set temperature; light with the target is emitted from the front end of the collimator; the front end of the collimator is connected to the optical platform through a support column; the position of the tail end of the collimator in the three-dimensional space is controlled by the three-dimensional adjustment displacement device to adjust the position of the target;

[0012] The environmental temperature test box is provided with nitrogen-filled films in front and back; the measured imaging device is arranged in the environmental temperature test box; the light with the target emitted from the front end of the collimator enters the measured imaging device through the nitrogen-filled film in front of the environmental temperature test box;

[0013] The photoelectric autocollimator is located behind the environmental temperature test box; the light path is monitored and calibrated through the nitrogen-filled film behind the environmental temperature test box.

[0014] The support column comprises an upper half and a lower half; the upper half of the support column is movably connected with the front end of the collimator; the lower half of the support column is fixedly connected with the optical platform; the upper half of the support column is movably connected with the lower half of the support column.

[0015] The three-dimensional adjustment displacement device comprises: a three-dimensional adjustment mechanical structure part and a three-dimensional rotation driving and closed-loop control part;

[0016] The three-dimensional adjustment mechanical structure part comprises: two vertical circular arc guide rails, a horizontal circular arc guide rail, a horizontal bearing and a vertical thrust bearing; the horizontal circular arc guide rail is installed on the optical platform; the two vertical circular arc guide rails are slidably connected with the horizontal circular arc guide rail through a first sliding rail; the tail end of the collimator is slidably connected with the two vertical circular arc guide rails through a second sliding rail.

[0017] The three-dimensional rotation driving and closed-loop control part comprises: a circular arc guide rail driving, a grating ruler feedback device and a three-dimensional rotation control system; the circular arc guide rail driving and the grating ruler feedback device are connected with the three-dimensional rotation control system; the first sliding rail and the second sliding rail are controlled to slide by the three-dimensional rotation control system; the rotation angle of the collimator in the horizontal direction and the vertical direction is obtained by the grating ruler feedback device.

[0018] The grating ruler feedback device specifically comprises a first grating ruler and a second grating ruler; specifically, the upper half of the support column is connected with the front end of the parallel light pipe through the first grating ruler arranged vertically, and the upper half of the support column is connected with the lower half of the support column through the second grating ruler arranged horizontally.

[0019] The environmental temperature test box is further provided with a two-dimensional rotary table and a vibration isolation table, and the measured imaging device is installed on the two-dimensional rotary table through a tool, and the two-dimensional rotary table is arranged on the vibration isolation table.

[0020] The second technical solution of the present application is a high-precision imaging device high-low temperature optical axis stability test method, comprising:

[0021] S1, system optical axis calibration, specifically: using a collimator to calibrate the optical axis of the collimated light source and the window of the environmental temperature test box;

[0022] S2, start the test system, specifically: turn on the three-dimensional adjustment displacement device, the two-dimensional rotary table, the environmental temperature test box, the photoelectric autocollimator and the control processing computer;

[0023] S3, set the initial state of the measured imaging device, specifically: fix the measured imaging device on the two-dimensional rotary table in the test box through a tool, connect the image output port of the measured imaging device to the acquisition card of the control processing computer, open the software to observe the image, and set the temperature of the environmental temperature test box to T1;

[0024] S4, adjust the black body to make the imaging device clearly distinguish, specifically: select a suitable cross target, and adjust the black body temperature to make the image clearly distinguish the target;

[0025] S5, obtain the initial position of the measured imaging device, specifically: control the three-dimensional adjustment displacement device to move the parallel light pipe, so that the cross center of the measured imaging device coincides with the cross of the target, read the reading of the grating ruler feedback device of the three-dimensional adjustment displacement device, and obtain the initial horizontal position x o and the vertical position y o of the measured imaging device;

[0026] S6, obtain the final position of the measured device, specifically: set the temperature of the environmental temperature test box to T2, and after the temperature of the environmental temperature test box is stable for a period of time, control the three-dimensional adjustment displacement device again to make the cross center of the measured imaging device in the image coincide with the cross of the target, and read the horizontal position x1 and the vertical position y1 of the measured imaging device at this time through the grating ruler feedback device of the three-dimensional adjustment displacement device;

[0027] S7, acquire system error, specifically: fix the working temperature of the measured imaging device tooling, two-dimensional turntable, vibration isolation table to T2, use the photoelectric autocollimator to measure the offset through the process mirror pasted on the measured imaging device, the deviation is the horizontal error δx and the vertical error δy of the measured imaging device after experiencing temperature change from T1 to T2;

[0028] S8, calculate the optical axis deviation of the imaging device, specifically: through the initial horizontal position x o and vertical position y o of the measured imaging device, horizontal position x1 and vertical position y1 and horizontal error δx and vertical error δy after experiencing temperature change from T1 to T2, calculate the horizontal optical axis deviation Δx = x1-x0-δx and the vertical optical axis deviation Δy = y1-y0-δy of the measured imaging device after experiencing temperature change from T1 to T2;

[0029] S9, repeat steps S3 to S8 three times to obtain the optical axis stability data of the imaging device under T1 to T2 temperature change.

[0030] The beneficial effects of the present application: the device and method of the present application, through three-dimensional high-precision rotating collimator, use nitrogen-filled film as the window of the environmental temperature test box, increase the shock isolation treatment of the environmental temperature test box, and obviously improve the test precision of the system. On the three-dimensional rotation of the collimator, an electric horizontal and vertical circular arc guide rail is designed to drive the movement of the collimator, and a high-precision grating ruler is installed on the rotating shaft as a position feedback, so that the high-precision movement of the collimator becomes a reality. Combined with the high-precision movement of the collimator, the nitrogen-filled film and the vibration isolation treatment of the oven, the order of magnitude of the optical axis stability test result of the system on the measured device is improved by the order of magnitude, which meets the high-precision test requirements of the optical axis stability of the imaging device. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is the system block diagram of the present application;

[0032] Figure 2 It is the system block diagram of the present application;

[0033] Figure 3 It is the support column structure diagram of the present application;

[0034] Figure 4 It is the optical axis stability test method flow chart;

[0035] Wherein, 1 is a collimator, 2 is a vertical circular arc guide rail, 3 is a horizontal circular arc guide rail, 4 is a horizontal bearing (grating ruler feedback), 5 is a vertical thrust shaft (grating ruler feedback), 6 is an optical platform, 7 is an environmental temperature test box, 8 is a two-dimensional rotary table, 9 is a measured device, 10 is a nitrogen-filled film window, 11 is a photoelectric autocollimator, 12 is a vibration isolation table, 13 is a control processing computer, 14 is a target, 15 is a black body, 16 is a mirror, 17 is a high surface shape off-axis parabolic mirror, 18 is a high surface shape plane mirror, and 19 is a support column. DETAILED DESCRIPTION

[0036] In order to facilitate those skilled in the art to understand the technical content of the present application, the content of the present application is further explained below in combination with the drawings.

[0037] As shown in Figure 1 , Figure 2 , a high-precision imaging device high-low temperature optical axis stability testing device and method, the device includes a collimator 1, two vertical circular arc guide rails 2, a horizontal circular arc guide rail 3, a horizontal bearing (grating ruler feedback) 4, a vertical thrust shaft (grating ruler feedback) 5, an optical platform 6, an environmental temperature test box 7, a two-dimensional rotary table 8, a measured device 9, a nitrogen-filled film window 10, a photoelectric autocollimator 11, a vibration isolation table 12, a control processing computer 13, a target 14, a black body 15, a mirror 16, a high surface shape off-axis parabolic mirror 17, a high surface shape plane mirror 18, and a support column 19.

[0038] The two vertical circular arc guide rails 2 are installed on the horizontal circular arc guide rail 3 through a first sliding rail, and the tail of the collimator 1 is installed on the two vertical circular arc guide rails 2 through a second sliding rail; specifically, the tail of the collimator 1 is bolted to the second sliding rail.

[0039] As shown in Figure 3 , a support column 19 structure schematic view, the support column 19 includes an upper half and a lower half; the front part of the collimator is fixedly connected with the horizontal bearing 4, the horizontal bearing 4 is movably connected with the upper half of the support column 19, the upper half of the support column 19 is fixedly connected with the vertical thrust shaft 5, the vertical thrust shaft 5 is movably connected with the lower half of the support column 19, and the lower half of the support column 19 is fixed on the optical platform.

[0040] The movement of the tail of the collimator 1 on the vertical circular arc guide rail 2 and the horizontal circular arc guide rail 3 is specifically realized by a three-dimensional rotary drive and closed-loop control system, so as to simulate the high-precision movement of the target; the three-dimensional rotary drive and closed-loop control system comprises a circular arc guide rail drive, a grating ruler feedback and a three-dimensional rotary control system, the circular arc guide rail drive and the grating ruler feedback are connected with the three-dimensional rotary control system, the circular arc guide rail drive is controlled by the three-dimensional rotary control system, so as to drive the sliders of the first slide rail and the second slide rail to slide respectively; the rotation angle of the collimator in the horizontal direction and the vertical direction is obtained by the grating ruler feedback.

[0041] As shown in Figure 3 The grating ruler feedback part specifically comprises a first grating ruler vertically arranged on the upper half of the support column 19 and a second grating ruler horizontally arranged on the lower half of the support column 19, the horizontal bearing 4 is movably connected with the first grating ruler, and the vertical thrust shaft 5 is movably connected with the second grating ruler.

[0042] The angle of the collimator rotating in the vertical direction is obtained by the first grating ruler vertically arranged on the upper half of the support column 19, and the angle of the collimator rotating in the horizontal direction is obtained by the second grating ruler horizontally arranged on the lower half of the support column 19.

[0043] The grating ruler feedback device is connected with the three-dimensional rotary control system, the three-dimensional rotary control system reads the value of the grating ruler feedback device, combines the closed-loop control of the two vertical circular arc guide rails and the horizontal circular arc guide rail set by the user, and forms the three-dimensional rotary drive and closed-loop control system with the collimator.

[0044] The environment temperature test box is provided with a nitrogen-filled film at the front and the back, the measured imaging device is arranged in the environment temperature test box, and the light with the target emitted from the front end of the collimator enters the measured imaging device through the nitrogen-filled film in front of the environment temperature test box; the environment temperature test box further comprises a two-dimensional turntable 8 and a vibration isolation table 12, the measured imaging device 9 is mounted on the two-dimensional turntable 8 through a tool, and the two-dimensional turntable 8 is arranged on the vibration isolation table 12; the two-dimensional turntable 8 is specifically a macro step two-dimensional turntable.

[0045] The photoelectric autocollimator 11 is located on the other side of the environment temperature test box, and functions as monitoring and adjusting the light path.

[0046] The variable-temperature target system is used for simulating the infinite target, and specifically comprises a high-emissivity surface source blackbody 15 and a high-emissivity target 14.

[0047] The testing device also comprises a large-aperture long-focus high-surface-shaped off-axis parabolic mirror and a high-surface-shaped plane mirror; the high-surface-shaped off-axis parabolic mirror 17 is arranged at the tail of the collimator 1, and the target provided by the variable-temperature target system reaches the high-surface-shaped off-axis parabolic mirror 17 after being reflected by the high-surface-shaped plane mirror 18 arranged at the front end of the collimator, and then reaches the imaging device to be tested from the nitrogen-filled film in front of the environmental temperature test chamber after being focused by the high-surface-shaped off-axis parabolic mirror 17.

[0048] The device also comprises a control processing computer, a three-dimensional rotation driving and closed-loop control system, an environmental temperature test chamber, a device to be tested and an autocollimator, which are linked with the control processing computer through a cable to form a high-precision imaging device high-low temperature optical axis stability testing system device.

[0049] The device of the present application is different from the prior art, and a long-focus large-aperture light source collimation system capable of three-dimensional adjustment is proposed, which improves the traditional testing method that can only realize optical axis reference calibration, optical axis deviation and optical axis stability testing by moving the thermal imager, and has the following advantages:

[0050] The nitrogen-filled film window is used to replace the traditional germanium mirror, the optical refractive index of the nitrogen-filled film window is extremely low and the optical transfer function is negligible, while the high refractive index of the traditional germanium glass window will cause refraction of the light path, so that the window needs to be vertically calibrated, and the introduction of the high optical transfer function cannot reflect the actual optical performance of the thermal imager lens;

[0051] The system of the present application fully considers the vibration isolation treatment caused by the compressor of the temperature chamber and reduces other influencing conditions of the optical axis stability testing to a very low level;

[0052] A high-collimation three-dimensional adjustment autocollimator is used as the calibration of the system optical axis reference;

[0053] Based on the sub-pixel algorithm, the high-precision optical axis deviation, field angle, zero walking and installation reference surface testing have a testing precision improved from the traditional 1 pixel to 0.01 pixel, so as to fully ensure the testing reliability, accuracy and repeatability of the optical axis deviation, field angle, zero walking and installation reference surface;

[0054] The optical axis stability detection device of the present application has the functions of three-dimensional adjustment of the light source collimation system, high-precision high-low temperature and humidity experiment, three-dimensional adjustment of the testing product, product data acquisition and analysis, and infrared collimation system calibration, and is a device necessary for optical axis stability detection of imaging device research and development, production, debugging and testing.

[0055] As shown in Figure 4 The flowchart of testing multiple refrigeration-type infrared detectors is shown in the present application, and the specific testing method comprises the following steps:

[0056] Step 1: optical axis calibration of the system

[0057] Calibration of collimated light source, environmental temperature test chamber window system using collimator, to ensure the accuracy of the initial optical axis of the test system.

[0058] Step 2: Start the test system

[0059] Open the three-dimensional adjustment device of the long focal length large aperture self-collimation system, the macro step two-dimensional turntable, the special environmental temperature test chamber, the photoelectric autocollimator and the test system software.

[0060] Step 3: Set the initial state of the measured imager

[0061] Fix the measured imaging device on the fixture of the micro step two-dimensional turntable in the test chamber, connect the image output port to the acquisition card of the computer, open the software to observe the image, and set the temperature of the environmental temperature test chamber to T1.

[0062] Step 4: Adjust the black body to clearly distinguish the imager

[0063] Select a suitable cross target, and adjust the black body temperature to clearly distinguish the target.

[0064] Step 5: Obtain the initial position of the measured device

[0065] Control the three-dimensional adjustment device to move the collimator, so that the cross center of the measured imaging device coincides with the cross of the target, read the reading of the controller of the three-dimensional adjustment device, and obtain the initial horizontal position x o and the vertical position y o of the optical axis of the measured imaging device.

[0066] Step 6: Obtain the final position of the measured device

[0067] Set the temperature of the temperature chamber to T2, and after the temperature of the temperature chamber is stable for a period of time, control the three-dimensional adjustment device again to make the cross center of the measured imaging device in the image coincide with the cross of the target, and read the horizontal position x1 and the vertical position y1 of the measured imaging device at this time through the controller of the three-dimensional adjustment device. T2≠T1. The specific time of the temperature stable for a period of time is set according to the actual test needs.

[0068] Step 7: Obtain the system error

[0069] Measure the error of the thermal imager fixture, two-dimensional turntable and vibration isolation table, reach the temperature (T2) to be tested, and use the photoelectric autocollimator to measure the offset through the process mirror pasted on the product. The deviation is the horizontal error δx and the vertical error δy of the system after experiencing temperature change.

[0070] Step 8: Calculate the optical axis deviation of the imager

[0071] By the initial position, the final position and the deformation error, the horizontal optical axis deviation Δx = x1 - x0 - δx and the vertical optical axis deviation Δy = y1 - y0 - δy of the measured imaging device from temperature T1 to T2 can be calculated. This method has the advantages of good repeatability, high precision and strong reliability.

[0072] Step 9: Repeat steps 3 to 8 three times to calculate the average of the optical axis deviation direction angle of the imaging device to evaluate the optical axis stability of the imaging device at high and low temperatures. Those skilled in the art should know that the optical axis stability of the imaging device at high and low temperatures in step 9 here refers to the horizontal optical axis deviation Δx and the vertical optical axis deviation Δy of the measured imaging device from temperature T1 to T2.

[0073] Those skilled in the art will realize that the embodiments described herein are for the purpose of helping the reader understand the principles of the present application and should be understood as not limiting the scope of protection of the present application to such specific statements and embodiments. The present application can have various modifications and changes for those skilled in the art. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the claims of the present application.

Claims

1. A high-precision imaging device high-low temperature optical axis stability testing device, characterized in that, The application relates to a collimator system, an environmental temperature test box, a photoelectric autocollimator, an optical platform and a control processing computer; the collimator system, the environmental temperature test box and the photoelectric autocollimator are arranged on the optical platform; the collimator system, the environmental temperature test box, the measured imaging device and the photoelectric autocollimator are connected with the control processing computer through cables. The collimator system comprises a collimator, a variable-temperature target system and a three-dimensional adjusting displacement device; the variable-temperature target system is used for providing a target; light with the target is emitted from the front end of the collimator; the front end of the collimator is connected to the optical platform through a support column; the position of the tail end of the collimator in the three-dimensional space is controlled through the three-dimensional adjusting displacement device to adjust the position of the target emitted from the front end of the collimator. The three-dimensional adjusting displacement device comprises a three-dimensional adjusting mechanical structure part and a three-dimensional rotating driving and closed-loop control part. The three-dimensional adjusting mechanical structure part comprises two vertical circular arc guide rails, a horizontal circular arc guide rail, a horizontal bearing and a vertical thrust bearing; the horizontal circular arc guide rail is arranged on the optical platform; the two vertical circular arc guide rails are slidably connected with the horizontal circular arc guide rail through a first sliding rail; the tail end of the collimator is slidably connected with the two vertical circular arc guide rails through a second sliding rail. The three-dimensional rotating driving and closed-loop control part comprises a circular arc guide rail driving, a grating ruler feedback device and a three-dimensional rotating control system; the circular arc guide rail driving and the grating ruler feedback device are connected with the three-dimensional rotating control system; the first sliding rail and the second sliding rail are controlled to slide through the three-dimensional rotating control system; the rotating angle of the collimator in the horizontal direction and the vertical direction is obtained through the grating ruler feedback device. The variable-temperature target system comprises a high-emissivity surface source blackbody and a high-emissivity target. Nitrogen-filled films are arranged in front of and behind the environmental temperature test box; the measured imaging device is arranged in the environmental temperature test box; the light with the target emitted from the front end of the collimator enters the measured imaging device through the nitrogen-filled film in front of the environmental temperature test box; a two-dimensional turntable and a vibration isolation table are arranged in the environmental temperature test box; the measured imaging device is arranged on the two-dimensional turntable through a tooling; the two-dimensional turntable is arranged on the vibration isolation table. The photoelectric autocollimator is arranged behind the environmental temperature test box; the light path is monitored and calibrated through the nitrogen-filled film behind the environmental temperature test box. The support column comprises an upper half and a lower half; the upper half of the support column is movably connected with the front end of the collimator; the lower half of the support column is fixedly connected with the optical platform; the upper half of the support column is movably connected with the lower half of the support column. 2.The high-precision imaging device high-low temperature optical axis stability testing device according to claim 1, wherein The grating ruler feedback device comprises a first grating ruler and a second grating ruler; specifically, the upper half of the support column is connected with the front end of the collimator through the vertically arranged first grating ruler; the upper half of the support column is connected with the lower half of the support column through the horizontally arranged second grating ruler.

3. The high-precision imaging device high-low temperature optical axis stability testing device according to claim 2, characterized in that, ​ 4. The high-precision imaging device high-low temperature optical axis stability testing device according to claim 3, characterized in that, The testing device further comprises a large-aperture long-focus high-surface-form off-axis parabolic mirror and a high-surface-form plane mirror; the high-surface-form off-axis parabolic mirror is arranged at the tail of the collimating tube, and the high-surface-form plane mirror is arranged at the front end of the collimating tube; the target provided by the variable-temperature target system is reflected by the high-surface-form plane mirror and then reaches the high-surface-form off-axis parabolic mirror (17), and after being focused by the high-surface-form off-axis parabolic mirror (17), the target enters the measured imaging device from the nitrogen-filled film in front of the environmental temperature test box.

5. A high-precision imaging device high-low temperature optical axis stability testing method, which is based on the testing device of any one of claims 1-3 and is used for testing the high-low temperature optical axis stability of the measured imaging device, and specifically comprises the following steps: S1, optical axis calibration of the testing device: using the photoelectric autocollimator to calibrate the optical axis of the collimating light source and the window of the environmental temperature test box; S2, starting the testing device: turning on the three-dimensional adjusting displacement device, the two-dimensional turntable, the environmental temperature test box, the photoelectric autocollimator and the control processing computer; S3, setting the initial state of the measured imaging device: fixing the measured imaging device on the two-dimensional turntable in the test box through a tool, connecting the image output port of the measured imaging device to the acquisition card of the control processing computer, opening the software to observe the image, and setting the temperature of the environmental temperature test box to T1; S4, adjusting the high-emissivity surface source black body to make the measured imaging device clearly distinguish: selecting a suitable cross target and adjusting the temperature of the high-emissivity surface source black body to make the image clearly distinguish the target; S5. Obtain the initial position of the imaging device under test: Control the three-dimensional adjustment displacement device to move the collimator so that the crosshair of the imaging device under test coincides with the crosshair of the target. Read the reading of the grating ruler feedback device of the three-dimensional adjustment displacement device to obtain the initial horizontal position x of the imaging device under test. o and vertical position y o ; S6, acquiring the final position of the measured imaging device: setting the temperature of the environmental temperature test box to T2, and after the temperature of the environmental temperature test box is stable, controlling the three-dimensional adjusting displacement device again to make the cross center of the measured imaging device in the image coincide with the cross of the target, and reading the horizontal position x1 and the vertical position y1 of the measured imaging device at this time through the grating ruler feedback device of the three-dimensional adjusting displacement device; S7, acquiring the system error: fixing the temperature of the tool, the two-dimensional turntable and the vibration isolation table of the measured imaging device to T2, and measuring the deviation amount through the process mirror pasted on the measured imaging device by using the photoelectric autocollimator, wherein the deviation amount is the horizontal error δx and the vertical error δy of the measured imaging device after the temperature changes from T1 to T2; S8, calculating the imaging device optical axis deviation: through the measured imaging device initial horizontal position x o and vertical position y o , horizontal position x1and vertical position y1and horizontal error δx and vertical error δy after experiencing temperature change from T1 to T2, the horizontal optical axis deviation ∆x=x1-x0-δx of the measured imaging device after experiencing temperature change from T1 to T2, the vertical optical axis deviation ∆y=y1-y0-δy; S9, repeating steps S3 to S8 three times to acquire the optical axis stability data of the measured imaging device under the temperature change from T1 to T2.

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