CN202793738U - Lens resolution detecting device - Google Patents

Abstract

A lens discrimination rate detection device, which consists of a base, an X-axis displacement platform, a Y-axis displacement platform, a supporting plate, an illuminating light source, a support structure, and a fixed fixed diffuser and a discrimination rate plate from bottom to top. Structure, lens to be detected, camera, bracket; the moving directions of the X-axis displacement platform and the Y-axis displacement platform are horizontal and perpendicular to each other, forming a two-dimensional mobile platform and fixed on the base; the supporting plate is fixed on the The Y-axis displacement table described above; the illumination source is fixed on the supporting plate; the fixing frame is fixed on the supporting plate through the support structure; the fixed structure is used to fix the scattering sheet and the identification rate plate, the scattering sheet is located under the identification rate plate, the frosted surface of the scattering sheet is placed upwards, and the side of the identification rate plate engraved with graphics is placed upwards; the lens to be detected and the camera are fixed on the bracket . The utility model has the advantages of easy construction, accurate and fine operation, objective evaluation and the like.

Description

Lens discrimination detection device

technical field

The utility model relates to a time optical lens, in particular to a lens discrimination rate detection device.

Background technique

With the development of science and the advancement of technology, people have higher and higher requirements for the quality of the acquired images; and the quality of the acquired images is closely related to the quality of the lens used, and devices that can effectively identify the imaging quality of the lens have a wide market.

At present, there are relatively mature lens inspection instruments on the market, but such instruments are only manufactured by a few foreign companies, and the price is high and the operation is cumbersome. They are only suitable for professional fields and are not conducive to popularization and application.

There are many standards for identifying lens quality, and measuring its identification rate is a widely used method. This method is simple and practical, and can effectively identify lens quality. In the prior art, there is a lens discrimination measurement device (utility model patent, application number 200920235085.6), which meets the requirements of economy and ease of use, but has the following disadvantages:

(1) It can only simply measure the imaging quality of the imaging field of view, and cannot form a fine evaluation of each field of view point in the entire field of view area;

(2) There is no discriminative rate board leveling structure, and the error of the measurement result is large;

(3) It is inconvenient to replace the light source, and it is impossible to evaluate different lenses;

(4) The light source directly illuminates the discrimination board, which is different from the real lighting situation.

Contents of the invention

The problem to be solved by the utility model is to overcome the deficiencies of the above-mentioned prior art and provide a lens discrimination rate detection device, which should be able to accurately, finely, objectively and systematically detect the imaging quality of the lens.

The technical solution of the utility model is as follows:

A lens discrimination rate detection device is characterized in that its composition includes a base, an X-axis displacement platform, a Y-axis displacement platform, a supporting plate, an illumination source, a supporting structure, and a fixed scattering sheet and a discrimination rate plate from bottom to top. The fixed structure, the lens to be tested, the camera, the bracket;

The moving directions of the X-axis displacement platform and the Y-axis displacement platform are horizontal and perpendicular to each other, forming a two-dimensional mobile platform and fixed on the base; the supporting plate is fixed on the Y-axis displacement platform; the The lighting source described above is fixed on the supporting plate; the fixing frame is fixed on the supporting plate through a support structure; the fixed structure is used to fix the scattering sheet and the identification rate plate, and the scattering sheet is located under the identification rate plate , the matte side of the scattering sheet is placed upwards, and the side of the identification rate plate engraved with graphics is placed upwards; the lens and camera to be tested are fixed on the bracket.

The wavelength of the illumination light source matches the working wavelength range of the lens to be tested.

The effect and design basis of each part of the utility model are as follows:

The two-dimensional mobile platform is used to adjust the horizontal relative position between the discrimination rate plate fixed by the fixed structure and the camera, and is used for testing different field of view points in the full field of view;

The function of the supporting plate is to provide middleware, reduce the dependence of other components on the installation holes of the two-dimensional mobile platform, and enhance the replaceability of system components;

The illumination light source is any light source that meets the measurement requirements, and its selection basis is the working wavelength range of the lens to be tested;

The function of the support structure is to support the fixed structure and adjust the pitch and height of the identification rate board fixed by the fixed structure;

The scattering sheet fixed by the fixed structure is replaced according to the lens to be tested, and the effect is to make the light output of the discrimination rate plate close to the actual light emission or illumination of the sample;

The discrimination rate board fixed by the fixed structure is one of a commercial discrimination rate board (also known as a resolution board) and a self-made discrimination rate board, which is selected according to the measurement requirements;

The relative horizontal position of the illumination source and the discrimination rate board fixed by the fixed structure can be adjusted, that is, the illumination source can illuminate the discrimination rate graphs of different line pairs of the discrimination rate board;

The above-mentioned camera is a kind of commercial digital camera, and its photos are required to be easily observed by human eyes and can be stored and analyzed by computer;

The mechanical components such as the supporting plate, supporting structure and fixing structure, adopt a simple design under the condition of meeting the requirements, to maximize the system reconfigurability and ease of construction;

The advantages of the utility model are reflected in the lens detection process, and the complete detection process of the utility model includes the following steps:

1. First, select the lighting source and identification rate board that meet the testing requirements;

2. Install and adjust the device so that the discriminant board has the level of the side where the graphics are written;

3. Adjust the device so that the optical axis of the lens is vertical, the image plane coincides with the imaging plane of the camera, and the object plane coincides with the side with the pattern engraved on the discriminative rate plate;

4. Turn on the lighting source and illuminate the identification rate board;

5. The camera takes pictures of the identification rate board;

6. Analyze the camera photos of the identification rate board to obtain the resolution of the lens;

7. Repeat steps 1-6 several times to process test results and reduce errors;

8. Adjust the two-dimensional translation platform according to certain rules, repeat steps 1-7, and measure several points in the field of view according to requirements;

9. According to the target to be tested, replace the light source and repeat steps 1-8;

10. After the test is over, summarize and analyze the test results and generate a test report.

The technical effect of the utility model is as follows:

The utility model fully considers the principle of reconstruction, is beneficial to installation and replacement of components, and is convenient for debugging.

The testing system of the utility model is placed on a two-dimensional translation platform, and by manually or electrically adjusting the two-dimensional translation platform, the fine evaluation of the imaging quality of different viewing field positions of the lens to be tested can be realized.

The pitch of the discriminant rate board of the utility model can be adjusted, and the surface of the discriminant rate board is adjusted to be perpendicular to the optical axis of the lens, so that measurement errors can be reduced.

The relative horizontal position of the illuminating light source and the identification rate board of the utility model can be adjusted, and the identification rate patterns of different line pairs can be used for measurement.

The light source of the utility model is easy to replace, so that the utility model can test the imaging quality of the lens under the illumination of different wavelength light sources.

In the utility model, a scattering sheet is installed between the lighting source and the identification rate board, which can simulate the actual lighting or lighting conditions of samples.

By using the utility model to evaluate the lens to be tested, the imaging quality of the lens can be known; the invention can not only accurately judge the identification rate of the lens, but also finely evaluate the imaging quality of the entire field of view of the lens, and the different light sources of the lens The following image quality is judged.

Popularizing and using the utility model will provide accurate, fine and objective lens detection device and method for identifying lenses.

Description of drawings

Fig. 1 is a schematic diagram of the lens discrimination rate detection device of the present invention.

Fig. 2 is a schematic diagram of a discriminative rate board in an embodiment of the present invention.

Fig. 3 is a schematic diagram of the test flow of the embodiment of the utility model.

Fig. 4 is a schematic diagram of selecting an object plane position according to an embodiment of the present invention.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model will be further described, but should not limit the protection scope of the utility model with this.

Referring to Fig. 1, Fig. 1 is a diagram of the lens discrimination rate detection device of the present invention, and it can be seen from the figure that the lens discrimination rate detection device of the present invention comprises a base 1, an X-axis displacement table 2, and a Y-axis from bottom to top. Directional displacement stage 3, supporting plate 4, illumination source 5, support structure 6, fixed structure 7 with scattering sheet and discrimination rate plate fixed, lens to be detected 8, camera 9, bracket 10;

The moving directions of the X-axis displacement platform 2 and the Y-axis displacement platform 3 are horizontal and perpendicular to each other, forming a two-dimensional mobile platform and fixed on the base 1; the supporting plate 4 is fixed on the Y-axis displacement platform. on the platform 3; the illumination source 5 is fixed on the supporting plate 4; the fixing frame 7 is fixed on the supporting plate 4 through the supporting structure 6; the fixing structure 7 is used for fixing the scattering sheet and identifying rate plate, the scattering sheet is located under the identification rate plate, the frosted surface of the scattering sheet is placed upwards, and the side of the identification rate plate engraved with graphics is placed upwards; the lens 8 to be detected and the camera 9 are fixed on the on the bracket 10.

The two-dimensional mobile platform is used to adjust the horizontal relative position of the discrimination rate plate fixed by the fixed structure 7 and the camera 9, and is used for testing different field of view points in the full field of view;

The function of the supporting plate 4 is to provide middleware, reduce the dependence of other components on the installation holes of the two-dimensional mobile platform, and enhance the replaceability of system components;

The illumination light source 5 is any light source that meets the measurement requirements, and its selection basis is the working wavelength range of the lens to be tested;

The function of the support structure 6 is to support the fixed structure 7 and adjust the pitch and height of the identification rate plate fixed by the fixed structure 7;

The scattering sheet fixed by the fixed structure 7 is replaced according to the lens to be tested, and is used to adjust the illumination of the discrimination rate board, so that the light emission of the discrimination rate board is close to the actual lighting or lighting conditions of the sample;

The discrimination rate board fixed by the fixed structure 7 is one of a commercial discrimination rate board (also known as a resolution board) and a self-made discrimination rate board, which is selected according to the measurement requirements;

The relative horizontal position of the identification rate board fixed by the illumination source 5 and the fixed structure 7 can be adjusted, that is, the illumination source 5 can illuminate the identification rate graphs of different line pairs of the identification rate board;

The camera 9 is a kind of commercial digital camera, and its photos are required to be convenient for human eyes to observe and can be stored and analyzed by a computer;

Below is the structure parameter of a concrete embodiment:

In this embodiment, the described two-dimensional mobile platform adopts a commercial two-dimensional manual mobile platform with a stroke of 120mm×120mm;

In this embodiment, it is required to measure the imaging quality of the lens under the light of 410nm~420nm. The illumination source 5 adopts a narrow-band light-emitting diode with a dominant wavelength of 410nm) for illumination, and a special-shaped drive circuit board is designed for this purpose. The circuit board has grooves , when fixed on the supporting plate 4 with screws, it can drive the light-emitting diode to move in the horizontal direction, and realize the translation adjustment without adding additional devices, which simplifies the complexity of the device; in order to enhance the adaptability of the system, the light-emitting diode Strong can be adjusted;

In this embodiment, the support structure 6 adopts a simple design, which simplifies the system to the greatest extent; it adopts a three-point support structure, one of which includes a screw with threads at both ends, a spring and two nuts, and there are respectively brackets between the two nuts and the spring. The plate 4 and the fixed structure 7, wherein the lower nut fixes the screw on the supporting plate 4, the upper nut and the spring form a push-pull structure, the adjustment of the upper nut can adjust the height of the fixed structure 7 at the corresponding support point, through the mutual cooperation of the three support points , to realize the pitch adjustment and height adjustment of the discrimination rate board fixed by the fixed structure 7;

In this embodiment, the fixed structure 7 is fixed with a scattering sheet and a discriminator board, and three grooves are designed to cooperate with the supporting structure 6. Drive the fixed discrimination rate board to move horizontally;

In this embodiment, the illumination light source 5 and the discrimination rate board can both move horizontally relative to the supporting plate 4, and the moving directions are perpendicular to each other, and the relative horizontal position of the illumination source 5 and the discrimination rate board fixed by the fixed structure 7 can be adjusted. ;

In this embodiment, the discrimination rate board adopts the 1951USAF type discrimination rate board, referring to accompanying drawing 2;

In this embodiment, the diffuser adopts ordinary frosted glass, and it is required that the illuminating light of the diffuser can illuminate the line-pair pattern of the required discriminative rate board, and can make the required discriminative rate board graphic be imaged on the camera 9;

In this embodiment, the camera 9 chooses a digital camera with a charge-coupled device (CCD) as the core, and chooses a digital camera. The photos are conveniently stored, which is beneficial to subsequent verification and analysis, and can use the powerful processing capabilities of computers to obtain more detailed evaluations;

For the test flow of this embodiment, refer to FIG. 3 .

During the test, first select the discrimination rate board and the lighting source according to the lens test requirements. As mentioned above, this embodiment uses a narrow-band light-emitting diode (LED) and a 1951USAF discrimination rate board; then, adjust the device to level the discrimination rate board , place the lens to be tested and adjust its posture, and adjust the illumination source to an appropriate brightness; finally, collect and analyze the camera photos of the identification rate board to obtain the identification rate of the lens.

In order to increase the universality of this system and reduce the difficulty of system construction, this embodiment uses visual inspection to analyze camera photos; if you want to obtain more objective results, you can use a computer to process the camera photos, and through computer processing, you can also get more detailed evaluation.

Repeat the measurement three times, and analyze and summarize the test results.

Adjust the two-dimensional translation stage to obtain the consistency of the discrimination rate of different field of view points in the field of view of the lens. The selection of the position should be representative. The selection of the position in this embodiment refers to FIG. 4 .

In this embodiment, since the light source used is determined by the purpose of the test, there is no need to replace the light source. If you need to measure the quality of white light lens, you can test with three light sources of red, green and blue respectively, and analyze the three components of red, green and blue in the camera photo respectively, so as to obtain the imaging quality of the lens for different primary color light sources.

Claims (2)

1. A lens discrimination rate detection device, characterized in that it consists of a base (1), an X-axis displacement table (2), a Y-axis displacement table (3), a supporting plate (4), Illumination light source (5), support structure (6), fixed structure (7) fixing the scattering sheet and discrimination rate plate, lens to be detected (8), camera (9), bracket (10); The moving directions of the X-axis translation platform (2) and the Y-axis translation platform (3) are horizontal and perpendicular to each other, forming a two-dimensional mobile platform and fixed on the base (1); the supporting plate (4) is fixed On the Y-axis displacement table (3); the illumination light source (5) is fixed on the supporting plate (4); the fixing frame (7) is fixed on the support structure (6) on the supporting plate (4); the fixed structure (7) is used to fix the scattering sheet and the identification rate board, the scattering sheet is located under the identification rate board, the frosted surface of the scattering sheet is placed upwards, and the identification rate board is engraved with One side of the graphics is placed upward; the lens (8) to be detected and the camera (9) are fixed on the bracket (10). 2. The lens discrimination rate detection device according to claim 1, characterized in that the wavelength of the illumination light source (5) matches the working wavelength range of the lens to be tested.

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