Calibration method and device for long-exit-pupil binocular near-to-eye display optical system

Abstract

The invention relates to the technical field of display, and discloses a calibration method and device for a long-exit-pupil binocular near-to-eye display optical system. Comprising an adjusting method and steps suitable for the long-exit-pupil binocular near-to-eye display optical system of the physiological protection augmented reality display helmet, and a set of binocular image combination testing and calibrating device designed based on the method and aiming at the binocular near-to-eye display optical system. The calibration device for the long-exit-pupil binocular near-to-eye display optical system is mainly composed of an optical calibration support table, a binocular simulation human eye camera set, anti-distortion calibration and image combination software and a PC processor. The adjustment and calibration problems of display consistency and personalized adaptation of a binocular near-to-eye display optical system of an existing physiological protection augmented reality display helmet are effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a calibration method and device for a long-exit-pupil binocular near-eye display optical system. Background Art

[0002] Near-eye display optical systems are widely used in fields such as augmented reality display and mixed reality. Based on the principle of binocular parallax, binocular near-eye display optical systems use two symmetrical optical paths, left and right, to provide independent images for each eye to achieve stereoscopic vision. The near-eye display optical system based on off-axis reflection is a type of near-eye display optical system, which is widely used in physiological protection augmented reality display helmets that require high-speed flight / ground driving environments. However, compared with other near-eye display optical systems, in order to meet the aerodynamic characteristics of high-speed flight, the final imaging optical surface of this optical system is a variable curved surface with a long exit pupil and large optical distortion. In addition, due to the manufacturing and installation errors of optical devices and optical path fixtures in the optical system and individual differences of users, this long exit pupil binocular near-eye display optical system is more prone to imaging errors during the adjustment process compared to other binocular near-eye display systems.

[0003] Based on the application characteristics of augmented reality display helmets in high-speed flight or ground driving environments, the present invention provides a calibration method and device for a long-exit-pupil binocular near-eye display optical system, which effectively solves the optical calibration problem of the near-eye optical display system and the physiological protection helmet structure. Summary of the invention

[0004] The purpose of the present invention is to provide a calibration method and device for a long exit pupil binocular near-eye display optical system, which effectively solves the display consistency and personalized adaptation calibration problems of the existing physiological protection augmented reality display helmet binocular near-eye display optical system through methods, steps and installation devices such as monocular machine optical axis adjustment test, monocular machine virtual image distance adjustment test, anti-distortion test and correction, binocular image combination and spatial consistency measurement.

[0005] The technical solution of the present invention is achieved in this way:

[0006] A calibration method for a long-exit-pupil binocular near-eye display optical system comprises the following steps:

[0007] The first step is to fix the standard projection reflection target surface on the optical calibration bracket, and measure the optical axis of the left and right optical machines respectively to ensure that the center of the left and right optical machine projection images can be collimated and projected on the imaging center of the test reflection target surface;

[0008] The second step is to conduct a consistency test of the virtual image distance of the single optical machine of the binocular near-eye display optical system through imaging measurement of the reflective target surface, so that the imaging focal length of the left and right optical machines is kept within a deviation of ±1% from the design value. If the index is not met, the virtual image distance is adjusted by adjusting the distance between the image source and the optical lens group of the optical machine and changing the object distance to meet the design requirements.

[0009] The third step is to adjust the relative position of the optical mask to be installed and the camera group simulating human eyes, so that the imaging centers of the left and right cameras of the camera group match the optically designed human eye pupil distance, and are aligned with the optical projection reflection center of the display mask to be installed;

[0010] The fourth step is to pre-install the bracket structure of the left and right optical machines on the optical calibration bracket based on the position of the camera group simulating the human eye and the optical design configuration, and adjust the posture of the left and right optical machines respectively through the axial and position fine-tuning functions of the optical calibration bracket, so that the imaging centers of the left and right optical machines are aligned with the structural center of the aspheric optical surface;

[0011] Step 5: Use the theoretical anti-distortion parameters obtained from optical design software such as code-V and z-max to generate the anti-distortion diagram of the optical machine display;

[0012] Step 6: The anti-distortion calibration software calculates the real distortion grid calibration data by analyzing the real optical and mechanical distortion distribution image obtained by the distortion-free camera, and generates a new anti-distortion image.

[0013] Step 7: Measure and calculate the real distortion distribution image of the single-lens machine again. If the center distortion and edge distortion values ​​cannot meet the distortion values ​​preset in the optical design, repeat step 6.

[0014] Step 8: Using the binocular parallax principle and the optical design parameters of the binocular near-eye display optical system, the left and right optical machine display images with parallax are generated in the anti-distortion calibration software.

[0015] In the ninth step, the distortion-free camera obtains the parallax display images of the left and right optical machines, and compares them with the theoretical parallax images through anti-distortion calibration and image combination software;

[0016] Step 10: Determine whether the image combination parameters need to be adjusted based on the actual image offset and twist obtained by the distortion calibration and image combination software;

[0017] Step 11: If the combined image does not reach the designed value, adjust the image generation parameters in the distortion calibration and combined image software, adjust the parallax image parameters for generating the left and right optical machines, and repeat step 9;

[0018] In the twelfth step, when the deviation between the actual disparity image generated by the left and right optical machines and the theoretical disparity image reaches the design value, the calibration of the binocular near-eye display optical system is completed.

[0019] A calibration device for a long-exit-pupil binocular near-eye display optical system, comprising:

[0020] Optical calibration bracket, a universal standard bracket constructed according to the long exit pupil characteristics of physiological protective helmets and the protective characteristics of imaging masks, used to fix and adjust the catadioptric binocular near-eye display optical system and binocular simulated human eye camera;

[0021] The binocular human eye simulation camera group is a left-right symmetrical zoom non-distortion camera that simulates the human eye to collect the projection display image of the binocular near-eye display optical system;

[0022] Anti-distortion calibration and image combination software, based on the image features obtained by the binocular simulated human eye camera group, the parameters of the human eye camera and the optical measurement calculation principle, calculates the optical indicators of the imaging center, virtual image distance and distortion distribution of the optical system, and compares and analyzes the theoretical and realized image combination effects based on the binocular parallax principle;

[0023] The PC processor is used to run the anti-distortion calibration and image combination software, and also serves as a hardware driver to provide display signals for the binocular near-eye display optical system.

[0024] As a further solution of the present invention: the optical calibration bracket consists of five modules: an optical adjustment substrate, an optical adjustment base, an optical display mask position adjustment platform, a left and right anti-distortion camera group position adjustment platform, and a left and right optical machine posture adjustment platform, which are used to fix and adjust the relative relationship between other modules of the device.

[0025] As a further solution of the present invention: the left and right anti-distortion camera group position adjustment platform is divided into left and right groups, which are respectively fixed on the optical adjustment substrate by fixing bolts. The front, rear, left and right relative positions of the left and right distortion-free zoom cameras can be changed by adjusting the stroke screw on the adjustment platform to match the pupil distance position of the optical design and align with the reflective display center of the optical display mask. The optical adjustment base is a bar-tooth structure fixed on the optical adjustment substrate as a base for vertical adjustment of the optical element; the left and right optical machine posture adjustment platform is divided into left and right symmetrical modules, one end of a single module is fixedly mounted on the optical adjustment base, and the other end is provided with a mounting screw hole for fixing and adjusting the posture of the optical machine.

[0026] As a further solution of the present invention: the posture adjustment platform of the left and right optical machines is a cantilever structure, which can provide horizontal and vertical position adjustment; the axial adjustment knob on the posture adjustment module at the end is used to provide optical structure fine-tuning in three axial rotation directions for the left and right optical machines.

[0027] As a further solution of the present invention: the optical display mask position adjustment platform is also installed on the optical adjustment base, and is also a multi-section cantilever structure, which is used for up and down adjustment and fixes the relative position of the optical display mask reflection imaging center relative to the simulated human eye camera group.

[0028] As a further solution of the present invention: the anti-distortion calibration and image combination software consists of a distortion camera image acquisition and processing module, a left and right optical-mechanical consistency rendering and display module, an optical axis center alignment analysis module, a virtual image distance measurement and analysis module, a distortion grid rendering and display module, a distortion measurement and analysis module, a binocular image combination rendering and display module, and a combination image comparison and analysis module.

[0029] As a further solution of the present invention: the binocular near-eye display optical system is composed of a left optical machine unit, a right optical machine unit, an optical display mask and a bracket for adjusting and curing the optical machine module bracket and the optical structure of the optical mask. Before adjustment and installation, the left optical machine unit, the right optical machine unit, the optical display mask and the bracket of the optical structure of the optical mask are all independent structural units whose posture relationships are not fully determined.

[0030] As a further solution of the present invention: after the optical posture structure and software parameters are confirmed, the optomechanical module bracket and the optical mask optical structure bracket are respectively connected through the left and right optomechanical connecting rods to fix the optical relationship between the optomechanical and the optical display mask, and the anti-distortion and image combination parameters of this adjustment are recorded.

[0031] Beneficial effects of the present invention:

[0032] 1. Aiming at the large optical distortion, long exit pupil binocular image formation and personalized spatial consistency display adjustment of the long exit pupil binocular near-eye display optical system of the physiological protection augmented reality display helmet in high-speed flight / driving environment, the present invention provides a set of standard and fast calibration methods, which can realize the fast adjustment and adaptation of the long exit pupil binocular near-eye display optical system, and greatly improve the work efficiency.

[0033] 2. The present invention is aimed at a long-exit-pupil binocular near-eye display optical system and provides an optical alignment and installation device that can realize single-optical machine virtual image distance adjustment test, anti-distortion test and correction, binocular image combination and spatial display consistency evaluation, thereby realizing the integration and high-precision installation of the long-exit-pupil binocular near-eye display optical system and achieving better spatial display effects.

[0034] 3. The present invention provides an optical adjustment method for different pupil distances, which greatly improves the personalized adaptation range of the fixed structure long exit pupil binocular near-eye display optical system.

[0035] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the execution flow of the calibration method of the long-exit-pupil binocular near-eye display optical system of the present invention;

[0037] Figure 2 A schematic diagram of the system composition of a binocular image combination test and calibration device for a long-exit-pupil near-eye display optical system of the present invention;

[0038] Figure 3 It is a schematic front view of the structure of the binocular image combination testing and calibration device of the present invention;

[0039] Figure 4 It is a schematic side view of the structure of the binocular image combination testing and calibration device of the present invention;

[0040] Figure 5 It is a schematic diagram of the module composition and calibration processing logic of the anti-distortion calibration and image combination software of the present invention;

[0041] Figure 6 It is a structural schematic diagram of the binocular near-eye display optical system of the present invention;

[0042] Figure 7 It is a schematic diagram of the binocular image combination testing and calibration device and the long exit pupil near-eye display optical system of the present invention.

[0043] The reference numerals in the figure are: left anti-distortion camera group 301a, right anti-distortion camera group 301b, optical adjustment substrate 302, left distortion-free zoom camera 303a, right distortion-free zoom camera 303b, optical adjustment base frame 304, posture adjustment platform 305, posture adjustment module 401, optical display mask position adjustment platform 402, left optical machine unit 601a, right optical machine unit 601b, optical display mask 602, adjustment and curing optical machine module bracket 603, optical mask optical structure bracket 604, optical machine connecting rod 701. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0045] See attached Figure 1-7 The present invention provides a calibration method and device for a long-exit-pupil binocular near-eye display optical system, which realizes the functions of optical-mechanical optical axis test, virtual image distance adjustment test, anti-distortion test and correction, binocular image combination and spatial display consistency evaluation of the long-exit-pupil binocular near-eye display optical system of a physiological protection augmented reality display helmet.

[0046] In the following embodiments, Embodiment 1 is the specific steps, processes, and the composition of each module of the corresponding device and the specific implementation case configuration of the invention, and Embodiment 2 is the specific implementation method of the method and device in a specific application scenario.

[0047] Embodiment 1

[0048] (1) The embodiments of the present invention include the following steps: Figure 1 As shown, in order to achieve the binocular combined image display effect of the long exit pupil binocular near-eye display optical system, the combined image adjustment of the binocular near-eye display optical system is divided into the following steps:

[0049] 1) The first step is to fix the standard projection reflective target surface on the optical calibration bracket, and measure the optical axis of the left and right optical machines respectively to ensure that the center of the left and right optical machine projection images can be collimated and projected on the imaging center of the test reflective target surface.

[0050] 2) The second step is to conduct a consistency test of the virtual image distance of the single optical machine of the binocular near-eye display optical system through imaging measurement of the reflective target surface, so that the imaging focal length of the left and right optical machines is kept within a deviation of ±1% from the design value. If the indicators are not met, the virtual image distance is adjusted by adjusting the distance between the image source and the optical lens group of the optical machine and changing the object distance to meet the design requirements.

[0051] 3) The third step is to adjust the relative position of the optical mask to be installed and the camera group simulating the human eye, so that the imaging centers of the left and right cameras of the camera group match the optically designed human eye pupil distance, and are aligned with the optical projection reflection center of the display mask to be installed.

[0052] 4) In the fourth step, based on the position of the camera group simulating the human eye and in accordance with the optical design configuration, the bracket structures of the left and right optical machines are pre-installed on the optical calibration bracket, and the axial and position fine-tuning functions of the optical calibration bracket are used to adjust the postures of the left and right optical machines respectively, so that the imaging centers of the left and right optical machines are aligned with the structural center of the aspheric optical surface.

[0053] 5) In the fifth step, the anti-distortion diagram of the optical machine display is generated using the theoretical anti-distortion parameters obtained by optical design software such as code-V and z-max.

[0054] 6) In the sixth step, the anti-distortion calibration software calculates the real distortion grid calibration data by analyzing the real optical and mechanical distortion distribution image obtained by the distortion-free camera, and generates a new anti-distortion image.

[0055] 7) In the seventh step, the real distortion distribution image of the single-lens machine is measured and calculated again. If the center distortion and edge distortion values ​​cannot meet the distortion values ​​preset in the optical design, repeat the sixth step.

[0056] 8) In the eighth step, using the binocular parallax principle and the optical design parameters of the binocular near-eye display optical system, the left and right optical machine display images with parallax are generated in the anti-distortion calibration software.

[0057] 9) In the ninth step, the distortion-free camera obtains the parallax display images of the left and right optical machines, and compares them with the theoretical parallax images through anti-distortion calibration and image combination software.

[0058] 10) In the tenth step, based on the actual image offset and twist obtained by the distortion calibration and image combination software, determine whether the image combination parameters need to be adjusted.

[0059] 11) In the eleventh step, if the combined image does not reach the designed value, adjust the image generation parameters in the distortion calibration and combined image software, adjust the parallax image parameters for generating the left and right optical machines, and repeat the ninth step.

[0060] 12) In the twelfth step, when the deviation between the actual disparity image generated by the left and right optical machines and the theoretical disparity image reaches the design value, the calibration of the binocular near-eye display optical system is completed.

[0061] (2) Figure 2 As shown in the system composition diagram, a calibration device for a long-exit-pupil binocular near-eye display optical system consists of an optical calibration bracket, a human eye simulation camera group, anti-distortion calibration and image synthesis software, and a PC processor for software operation and display hardware driver.

[0062] Among them, the optical calibration support platform is composed of five modules: an optical adjustment substrate, an optical adjustment base frame, an optical display mask position adjustment platform, a left and right anti-distortion camera group position adjustment platform, and a left and right optical machine posture adjustment platform, which are used to fix and adjust the relative relationship between other modules of the device. The simulated human eye camera group is composed of two left and right distortion-free zoom cameras, which are used to simulate the human eye and collect the display screen of the eye optical display system. The anti-distortion calibration and image combination software is configured on the PC processor to generate the imaging screen of the left and right optical machines of the optical system, and optically analyze the actual imaging screen of the left and right optical machines to obtain optical adjustment parameters, and according to the configuration adjustment parameters, optimize and generate new left and right optical machine anti-distortion and combination screens. The display interface of the PC processor is connected to the display driver board of the near-eye display optical system to realize the drive display of the binocular near-eye display optical system.

[0063] (3) Figure 3As shown in the structural schematic diagram, the left and right anti-distortion camera group position adjustment platform is divided into left and right groups 301a and 301b, which are fixed on the optical adjustment substrate 302 by fixing bolts respectively. By adjusting the travel screw on the adjustment platform, the front and rear left and right relative positions of the left and right distortion-free zoom cameras 303a and 303b can be changed to match the pupil distance position of the optical design and align with the reflective display center of the optical display mask. The optical adjustment base frame 304 is a bar-tooth structure, fixed on the optical adjustment substrate 302, and serves as a base for adjusting the optical element in the vertical direction. The left and right optical machine posture adjustment platform 305 is divided into left and right symmetrical modules, one end of a single module is fixedly mounted on the optical adjustment base 304, and the other end is provided with a mounting screw hole for fixing and adjusting the posture of the optical machine.

[0064] (4) Figure 4 As shown, the posture adjustment platform 305 of the left and right optical machines is a cantilever structure, which can provide horizontal and vertical position adjustment. In addition, through the posture adjustment module 401 at the end, the optical structure fine adjustment in three axial rotation directions can be provided for the left and right optical machines through the axial adjustment knob. The optical display mask position adjustment platform 402 is also installed on the optical adjustment base frame 304, and is also a multi-stage cantilever structure, which is used for up and down adjustment and fixes the relative position of the optical display mask reflection imaging center relative to the simulated human eye camera group.

[0065] (5) Figure 5 The software composition of the anti-distortion calibration and image combination software shown is mainly composed of a distortion camera image acquisition and processing module, a left and right optical-mechanical consistency rendering and display module, an optical axis center alignment analysis module, a virtual image distance measurement and analysis module, a distortion grid rendering and display module, a distortion measurement and analysis module, a binocular image combination rendering and display module, and a combination image comparison and analysis module.

[0066] (6) Figure 6 As shown, the composition and structural schematic diagram of the long exit pupil binocular near-eye display optical system for installation example is mainly composed of a left optical machine unit 601a, a right optical machine unit 601b, an optical display mask 602 and a bracket 604 for adjusting and curing the optical machine module bracket 603 and the optical structure of the optical mask. Before installation, the left and right optical machine units 601a and 601b, the optical display mask 602 and the bracket 604 of the optical structure of the optical mask are all independent structural units whose posture relationships are not fully determined.

[0067] (7) Figure 7As shown, it is a schematic diagram of the assembly of the long exit pupil near-eye display optical system in the binocular combination test and calibration device. According to the method provided above, the measurement cameras 303a and 303b of the binocular combination are used as the reference, the positions of the optical display mask 602 and the optical mask optical structure bracket 604 are fixed, and then the posture adjustment table 305 of the left and right optical machines is used in turn to adjust the posture of the left and right optical machine units 601a and 601b, perform image alignment, and realize the solidification of the optical position. Then, the test feedback parameters obtained by the left and right anti-distortion camera groups 303a and 303b and the anti-distortion correction and combination software are used to adjust the anti-distortion and combination parameters of the left optical machine unit 601a and the right optical machine unit 601b in turn. After confirming the combination effect, the solidification of the anti-distortion and combination parameters is completed. After the optical posture structure and software parameters are confirmed, the left and right optical machine connecting rods 701 are used to connect the optical machine module bracket 603 and the optical mask optical structure bracket 604 respectively, fix the optical relationship between the optical machine and the display mask, and record the anti-distortion and image combination parameters of this adjustment.

[0068] Embodiment 2

[0069] The schematic diagram of a specific embodiment of the binocular image combination test and calibration device and the long exit pupil near-eye display optical system of the present invention is shown in FIG. Figure 7 As shown, the specific implementation scheme is as follows:

[0070] Step 1: Follow the steps of Example 1. Figure 2 Perform hardware configuration and connection, then fix the reflective imaging target plate on the optical calibration bracket, adjust the travel screw, and change the left, right, and up and down distances of the distortion-free zoom camera so that its relative posture with the reflective imaging target plate is consistent with the optical design posture;

[0071] Step 2: Install the left and right optical machines on the optical calibration bracket, use the anti-distortion calibration and image combination software to measure the optical axis of the left optical machine, and confirm that the center of the projected image of the left and right optical machines is within the design error;

[0072] Step 3: Use anti-distortion calibration and image combination software to test the consistency of virtual image distance of the left and right optical machines, so that the imaging focal lengths of the left and right optical machines are kept within a deviation of ±1% from the design value. If the index is not met, adjust the distance between the image source and the optical lens group of the optical machine and change the object distance to adjust the virtual image distance to meet the design requirements;

[0073] Step 4: Disassemble the left and right optical machines, pre-install the optical display mask structure on the optical calibration bracket according to the optical design configuration, and adjust the relative position of the simulated human eye camera group to align it with the center distance of the lens plane of the optical display mask to match the optically designed human eye pupil distance;

[0074] Step 5: Re-install the left and right optical machines on the optical calibration bracket in turn, and adjust the postures of the left and right optical machines respectively through the axial and position fine-tuning functions of the optical frame calibration bracket, so that the imaging centers of the left and right optical machines are aligned with the structural center of the aspheric optical surface;

[0075] Step 6: Use the optical machine to fix the bracket, respectively connect the pre-adjustment brackets of the left and right optical machines with screws, and fill the gaps between the mounting interfaces with light-curing adhesive, so that the optical display mask 602 and the left optical machine unit 601a and the right optical machine unit 602b are cured into a stable optical structure;

[0076] Step 7: Dismantle the connection between the posture adjustment module 401 at the end of the posture adjustment platform of the left and right optical machines and the left and right optical machines;

[0077] Step 8: Use the theoretical anti-distortion parameters obtained from optical design software such as code-V and z-max to generate anti-distortion images of the left and right optical machine displays in the anti-distortion calibration and image combination software;

[0078] Step 9: The anti-distortion calibration software calculates the real distortion grid calibration data by analyzing the real optical-mechanical distortion distribution image obtained by the distortion-free camera, and generates a new anti-distortion image;

[0079] Step 10: Measure and calculate the real distortion distribution image of the single-lens machine again. If the center distortion and edge distortion values ​​cannot meet the distortion values ​​preset in the optical design, repeatedly adjust the distortion adjustment parameters to make the center distortion and edge distortion reach the designed values.

[0080] Step 11: Using the binocular parallax principle and the optical design parameters of the binocular near-eye display optical system, generate left and right optical machine display images with parallax in the anti-distortion calibration software;

[0081] Step 12: The distortion-free camera obtains the parallax display images of the left and right optical machines, and compares them with the theoretical parallax images through anti-distortion calibration and image combination software;

[0082] Step 13: Determine whether the image combination parameters need to be adjusted based on the actual image offset and twist obtained by the distortion calibration and image combination software;

[0083] Step 14: If the combined image does not reach the designed value, adjust the image generation parameters in the distortion calibration and combined image software, adjust the parallax image parameters for generating the left and right optical machines, and repeat step 11;

[0084] Step 15: When the deviation between the actual disparity image generated by the left and right optical machines and the theoretical disparity image reaches the design value, the calibration of the binocular near-eye display optical system is completed. At this time, it can be used for system assembly and wearing display testing of physiological protection helmets.

[0085] The present invention provides a calibration method and device for a long-exit-pupil binocular near-eye display optical system. Through methods, steps and adjustment devices such as monocular optical axis adjustment test, monocular virtual image distance adjustment test, anti-distortion test and correction, binocular image combination and spatial consistency measurement, the calibration problem of display consistency and personalized adaptation of the existing physiological protection augmented reality display helmet binocular near-eye display optical system is effectively solved. The device for the long-exit-pupil binocular near-eye display optical system consists of an optical calibration bracket, a human eye simulation camera group, anti-distortion calibration and image combination software, and a PC processor for software operation and display hardware drive.

[0086] In summary, the present invention provides an off-axis reflective binocular near-eye display optical system for high-speed protective helmets. Through all the system architectures, design principles, system structure diagrams and application examples in the abstract drawings, the device consistency measurement and optical binocular space adjustment are integrated into a process and mechanism device, realizing the integration and adjustment of the long exit pupil binocular near-eye display optical system, fundamentally solving the problems of unclear adjustment process, multiple equipment coordination, inconsistent optical benchmarks, etc. in the previous physiological protection augmented reality helmet optics, and effectively solving the optical calibration problem of the near-eye optical display system and the physiological protection helmet structure.

[0087] So far, the purpose of the present invention has been achieved.

[0088] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A calibration method for a long-exit-pupil binocular near-eye display optical system, characterized in that: The steps include: The first step is to fix the standard projection reflection target surface on the optical calibration bracket, and measure the optical axis of the left and right optical machines respectively to ensure that the center of the left and right optical machine projection images can be collimated and projected on the imaging center of the test reflection target surface; The second step is to conduct a consistency test of the virtual image distance of the single optical machine of the binocular near-eye display optical system through imaging measurement of the reflective target surface, so that the imaging focal length of the left and right optical machines is kept within a deviation of ±1% from the design value. If the index is not met, the virtual image distance is adjusted by adjusting the distance between the image source and the optical lens group of the optical machine and changing the object distance to meet the design requirements. The third step is to adjust the relative position of the optical mask to be installed and the camera group simulating human eyes, so that the imaging centers of the left and right cameras of the camera group match the optically designed human eye pupil distance, and are aligned with the optical projection reflection center of the display mask to be installed; The fourth step is to pre-install the bracket structure of the left and right optical machines on the optical calibration bracket based on the position of the camera group simulating the human eye and the optical design configuration, and adjust the posture of the left and right optical machines respectively through the axial and position fine-tuning functions of the optical calibration bracket, so that the imaging centers of the left and right optical machines are aligned with the structural center of the aspheric optical surface; Step 5: Use the theoretical anti-distortion parameters obtained from optical design software such as code-V and z-max to generate the anti-distortion diagram of the optical machine display; Step 6: The anti-distortion calibration software calculates the real distortion grid calibration data by analyzing the real optical and mechanical distortion distribution image obtained by the distortion-free camera, and generates a new anti-distortion image. Step 7: Measure and calculate the real distortion distribution image of the single-lens machine again. If the center distortion and edge distortion values ​​cannot meet the distortion values ​​preset in the optical design, repeat step 6. Step 8: Using the binocular parallax principle and the optical design parameters of the binocular near-eye display optical system, the left and right optical machine display images with parallax are generated in the anti-distortion calibration software. In the ninth step, the distortion-free camera obtains the parallax display images of the left and right optical machines, and compares them with the theoretical parallax images through anti-distortion calibration and image combination software; Step 10: Determine whether the image combination parameters need to be adjusted based on the actual image offset and twist obtained by the distortion calibration and image combination software; Step 11: If the combined image does not reach the designed value, adjust the image generation parameters in the distortion calibration and combined image software, adjust the parallax image parameters for generating the left and right optical machines, and repeat step 9; In the twelfth step, when the deviation between the actual disparity image generated by the left and right optical machines and the theoretical disparity image reaches the design value, the calibration of the binocular near-eye display optical system is completed.

2. A calibration device for a long-exit-pupil binocular near-eye display optical system, characterized in that: include: Optical calibration bracket, a universal standard bracket constructed according to the long exit pupil characteristics of physiological protective helmets and the protective characteristics of imaging masks, used to fix and adjust the catadioptric binocular near-eye display optical system and binocular simulated human eye camera; The binocular human eye simulation camera group is a left-right symmetrical zoom non-distortion camera that simulates the human eye to collect the projection display image of the binocular near-eye display optical system; Anti-distortion calibration and image combination software, based on the image features obtained by the binocular simulated human eye camera group, the parameters of the human eye camera and the optical measurement calculation principle, calculates the optical indicators of the imaging center, virtual image distance and distortion distribution of the optical system, and compares and analyzes the theoretical and realized image combination effects based on the binocular parallax principle; The PC processor is used to run the anti-distortion calibration and image combination software, and also serves as a hardware driver to provide display signals for the binocular near-eye display optical system.

3. The calibration method for a long-exit-pupil binocular near-eye display optical system according to claim 2, characterized in that: The optical calibration bracket consists of five modules: an optical adjustment substrate, an optical adjustment base, an optical display mask position adjustment platform, a left and right anti-distortion camera group position adjustment platform, and a left and right optical machine posture adjustment platform, and is used to fix and adjust the relative relationship between other modules of the device.

4. The calibration method for a long-exit-pupil binocular near-eye display optical system according to claim 3, characterized in that: The left and right anti-distortion camera group position adjustment platform is divided into left and right groups, which are respectively fixed on the optical adjustment substrate by fixing bolts. The front, rear, left and right relative positions of the left and right distortion-free zoom cameras can be changed by adjusting the stroke screw on the adjustment platform to match the pupil distance position of the optical design and align with the reflective display center of the optical display mask. The optical adjustment base is a bar-tooth structure fixed on the optical adjustment substrate as a base for vertical adjustment of the optical element; the left and right optical machine posture adjustment platform is divided into left and right symmetrical modules, one end of a single module is fixedly mounted on the optical adjustment base, and the other end is provided with a mounting screw hole for fixing and adjusting the posture of the optical machine.

5. The calibration method for a long-exit-pupil binocular near-eye display optical system according to claim 4, characterized in that: The posture adjustment platform of the left and right optical machines is a cantilever structure, which can provide horizontal and vertical position adjustment; the axial adjustment knob on the posture adjustment module at the end is used to provide optical structure fine-tuning in three axial rotation directions for the left and right optical machines.

6. The calibration method for a long-exit-pupil binocular near-eye display optical system according to claim 4, characterized in that: The optical display mask position adjustment platform is also installed on the optical adjustment base frame and is also a multi-section cantilever structure, which is used for up and down adjustment and fixes the relative position of the optical display mask reflection imaging center relative to the simulated human eye camera group.

7. The calibration method for a long-exit-pupil binocular near-eye display optical system according to claim 2, characterized in that: The anti-distortion calibration and image combination software consists of a distortion camera image acquisition and processing module, a left and right optical-mechanical consistency rendering and display module, an optical axis center alignment analysis module, a virtual image distance measurement and analysis module, a distortion grid rendering and display module, a distortion measurement and analysis module, a binocular image combination rendering and display module, and a combination image comparison and analysis module.

8. A calibration method for a long-exit-pupil binocular near-eye display optical system according to any one of claims 2 to 7, characterized in that: The binocular near-eye display optical system consists of a left optical machine unit, a right optical machine unit, an optical display mask, and a bracket for adjusting and curing the optical machine module bracket and the optical structure of the optical mask. Before adjustment and installation, the left optical machine unit, the right optical machine unit, the optical display mask, and the bracket of the optical structure of the optical mask are all independent structural units whose posture relationships are not fully determined.

9. The calibration method for a long-exit-pupil binocular near-eye display optical system according to claim 8, characterized in that: After the optical posture structure and software parameters are confirmed, the left and right optomechanical connecting rods are used to connect the optomechanical module bracket and the optical structure bracket of the optical mask respectively, fix the optical relationship between the optomechanical and the optical display mask, and record the anti-distortion and image combination parameters of this adjustment.

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