A micro optical module resolution detection device

Abstract

A resolution testing device for miniature optical modules comprises a resolution plate and its illumination assembly, an optical module under test and its adjustment mechanism, and a microscopic observation system and its adjustment mechanism arranged sequentially along the beam transmission direction. The microscopic observation system observes the resolution plate through the optical module under test and evaluates the optical performance of the optical module under test by observing the line group on the resolution plate. This testing device can perform resolution observation on structurally complex miniature optical modules, especially optical modules whose working main beam deviates from its mechanical axis, and obtain quantitative resolution test results, meeting the testing needs of miniature optical modules in fields such as AR / VR, endoscopes, and aerospace.

Description

Technical Field

[0001] This utility model relates to the field of optical lens processing, specifically a detection device for detecting the resolution of micro optical modules. Background Technology

[0002] Testing the resolution of optical lenses or optical modules is a routine task in the optical processing industry. The usual method is to use a collimator to form an object at infinity (resolution plate or crosshair plate), and observe the image from behind the part under test through a front mirror or other means to analyze the resolution of the lens.

[0003] However, in modern AR / VR, endoscopes, and aerospace equipment, many optical systems are small and complex. For example, in CN202323123689, the near-eye display optical module 42 is the core of the optical system. Its main working beam deviates from its mechanical axis, forming a folded telescope system with a deflected optical path. To test the resolution of such a deflected optical path microlens or optical module, a special testing device needs to be built. Utility Model Content

[0004] To address the problems mentioned in the background section, this utility model provides the following technical solution: A resolution testing device for a miniature optical module is characterized by the following: a resolution plate 2, an optical module under test 5, and a microscopic observation system 6 are arranged sequentially along the beam transmission direction. The line connecting the resolution plate 2 and the optical module under test 5 is the incident beam axis A, and the line connecting the optical module under test 5 and the microscopic observation system 6 is the outgoing beam axis B. The optical module under test 5 has a mechanical axis C. The incident beam axis A, the outgoing beam axis B, and the mechanical axis C are not collinear at the same time. The resolution of the optical module under test 5 is evaluated by observing the pattern on the resolution plate 2 through the microscopic observation system 6.

[0005] Furthermore, the incident beam axis A, the exit beam axis B, and the mechanical axis C are arranged horizontally.

[0006] Furthermore, the resolution plate 2 is illuminated by a diffuse light source 1, and the microscopic observation system 6 includes a zoom microscope lens 62, a CMOS camera 63, and a display screen 64.

[0007] Furthermore, the optical module 5 under test is mounted at the center of the rotating platform 3 and can rotate and be raised and lowered.

[0008] Furthermore, the resolution plate 2 is mounted on the resolution plate adjustment frame 21, which allows the resolution plate 2 to translate along axis A and in a plane perpendicular to axis A. The microscopic observation system 6 is mounted on the observation system adjustment frame 61, which allows the microscopic observation system 6 to translate along axis B and in a plane perpendicular to axis B, and also allows the microscopic observation system 6 to pitch relative to the horizontal plane.

[0009] Based on the above settings, the micro-optical module resolution detection device of this application has the following beneficial effects: it can perform resolution microscopic observation on micro-optical modules with complex structures, especially optical modules whose working main beam deviates from its mechanical axis, and obtain quantitative resolution detection results. Attached Figure Description

[0010] Figure 1 This is a diagram showing the observation setup when the B-axis deviates from the A-axis and C-axis. Figure 2 This is a diagram showing the observation setup when the C-axis deviates from the A-axis and B-axis. Figure 3 This is a schematic diagram of the resolution lines observed on the monitor screen.

[0011] In the figure: 1. Diffuse light source; 2. Resolution plate; 21. Resolution plate adjustment frame; 22. Resolution line; 3. Rotary lifting platform; 4. Base; 5. Optical module; 6. Microscopic observation system; 61. Observation system adjustment frame; 62. Zoom microscope lens; 63. CMOS camera; 64. Display screen. Detailed Implementation

[0012] The technical solutions in the embodiments of this utility model will be described below with reference to the accompanying drawings. It should be noted that the accompanying drawings are only used to explain the technical solutions of this application and are not drawn to scale. In fact, the inspected area of ​​the optical module 5 is smaller than a sesame seed, while the total length of the microscopic observation system 6 exceeds 300mm.

[0013] See Figure 1 and Figure 2 The optical module under test is the near-eye display optical module in CN202323123689, which has four working zones: the AR spot area at the center of the convex surface and the surrounding HR ring area, the HR spot area at the center of the concave surface and the surrounding AR ring area, as shown by the direction of the beam arrow in the figure. Its main working beam is deviated from the mechanical axis C of the optical module 5.

[0014] A resolution plate 2, an optical module under test 5, and a microscopic observation system 6 are arranged sequentially along the beam propagation direction. The line connecting the resolution plate 2 and the optical module under test 5 is the incident light axis A, the line connecting the optical module under test 5 and the microscopic observation system 6 is the outgoing light axis B, and the optical module under test 5 has a mechanical axis C. The three axes are arranged horizontally.

[0015] Figure 1 This is the observation layout diagram when the B-axis deviates from the A-axis and C-axis, and Figure 2 This is the observation layout diagram when the C-axis deviates from the A-axis and B-axis. The resolution plate 2 is illuminated by the diffuse light source 1. The microscopic observation system 6 is equipped with a display screen 64. The microscopic observation system 6 observes the resolution plate 2 through the optical module under test 5 and quantitatively evaluates the resolution of the optical module under test 5 by observing the line group of the resolution plate 2.

[0016] The optical module 5 is placed at the center of the rotating lifting platform 3, allowing it to rotate and rise. Since the optical module 5 is very small, the rotating lifting platform 3 can also be placed on the base 4. The resolution plate 2 is mounted on the resolution plate adjustment frame 21, which allows the resolution plate 2 to be moved along the A-axis and in a plane perpendicular to the A-axis. The microscopic observation system 6 is mounted on the observation system adjustment frame 61, which allows the microscopic observation system 6 to be moved along the B-axis and in a plane perpendicular to the B-axis, as well as to be tilted relative to the horizontal plane.

[0017] The microscopic observation system 6 includes a zoom microscope head 62, a CMOS camera 63, and a display screen 64. The zoom microscope head is, for example, a monocular microscope head with a zoom of 0.7 to 4.5 times, and the CMOS camera is, for example, a 2-megapixel global shutter industrial camera.

[0018] Based on the above arrangement, the image of resolution lines 22 can be seen on display screen 64, such as... Figure 3 Here, the resolution plate 2 is the national standard JBT 9328-1999_resolution plate, size A7. By observing the image of the lines, the resolution index of the optical module can be quantitatively obtained.

[0019] It should be noted that in the overall setup, the microscopic observation system 6 is relatively large, while the resolution plate 2 and optical module 5 are relatively small. Typically, the former is fixed in place first, and then the latter two are precisely fine-tuned. Figure 3 The imaging quality of the left and right areas can be clearly seen, but the upper and lower areas cannot be seen completely or well. There are two solutions: one is to rotate the mechanical axis of the optical module under test by 90° and then measure it; the other is to make appropriate pitch adjustments to the microscopic observation system 6. Due to its "large" size, this pitch angle can usually only be no more than ±15°.

[0020] It should be noted that, in order to reduce stray light interference and improve observation quality, a light shield (not shown in the figure) can be installed around the optical module 5, leaving light passages for the A and B axes. Alternatively, the light shield can be made larger to cover the entire detection device.

[0021] The embodiments of this utility model have been described above. Those skilled in the art can make modifications, substitutions, and variations to the embodiments without departing from the principles and spirit of this utility model, as long as they are within the scope of the claims of this utility model, they are protected by patent law.

Claims

1. A resolution detection device for a miniature optical module, characterized in that: A resolution plate (2), an optical module under test (5), and a microscopic observation system (6) are arranged sequentially along the beam propagation direction. The line connecting the resolution plate (2) and the optical module under test (5) is the incident beam axis A, and the line connecting the optical module under test (5) and the microscopic observation system (6) is the outgoing beam axis B. The optical module under test (5) has a mechanical axis C. The incident beam axis A, the outgoing beam axis B, and the mechanical axis C are not collinear at the same time. The resolution of the optical module under test (5) is evaluated by observing the pattern on the resolution plate (2) through the microscopic observation system (6).

2. The micro-optical module resolution detection device according to claim 1, characterized in that: The incident beam axis A, the exit beam axis B, and the mechanical axis C are arranged horizontally.

3. The micro-optical module resolution detection device according to claim 1, characterized in that: The resolution plate (2) is illuminated by a diffuse light source (1), and the microscopic observation system (6) includes a zoom microscope lens (62), a CMOS camera (63), and a display screen (64).

4. The micro-optical module resolution detection device according to claim 1, characterized in that: The optical module under test (5) is installed at the center of the rotating lifting platform (3) and can rotate and lift.

5. The micro-optical module resolution detection device according to claim 1, characterized in that: The resolution plate (2) is mounted on the resolution plate adjustment frame (21), which allows the resolution plate (2) to translate along axis A and in a plane perpendicular to axis A. The microscopic observation system (6) is mounted on the observation system adjustment frame (61), which allows the microscopic observation system (6) to translate along axis B and in a plane perpendicular to axis B, and allows the microscopic observation system (6) to pitch relative to the horizontal plane.

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