CN-121985110-A - Optical target based on three-dimensional cavity type structure

Abstract

The invention relates to an optical target based on a three-dimensional cavity structure, which comprises a black box body and a white plate, wherein a round hole is formed in one side surface of the black box body, a light absorption cavity is formed in the box body, the white plate is connected with the black box body and is arranged in the round hole, and an annular area communicated with the light absorption cavity is formed between the white plate and the black box body. When light irradiates the optical target, a part of light is reflected by the white plate, a part of light enters an annular area around the white plate and then enters the light absorption cavity, and the light is gradually attenuated after being reflected for multiple times in the cavity, so that an extremely low gray value which is close to a theoretical black body is formed at the annular area, a light spot formed on the white plate and the annular area are clear in boundary, and a good gray difference is formed between the light spot and the annular area.

Inventors

• LI MINGPENG
• ZHAO YANGSEN
• ZHU LIANWANG
• ZHENG GUIPING
• ZHENG ZHIQIANG
• DING LING
• WU XIAOXUE

Assignees

• 武汉珈鹰智能科技有限公司

Dates

Publication Date

20260505

Application Date

20260108

Claims (10)

1. 1. An optical target based on a three-dimensional cavity structure, comprising: A round hole is formed on one side surface of the black box body, and a light absorption cavity is formed in the box body; The white board is connected with the black box body and is arranged in the round hole, an annular area which is communicated with the light absorption cavity is formed between the white board and the black box body, and light rays are incident into the light absorption cavity through the annular area and are attenuated gradually in the cavity so as to form gray level difference between the annular area and the white board.
2. 2. The stereoscopic cavity-based optical target according to claim 1, wherein the black box is a cube.
3. 3. The stereoscopic cavity-based structure optical target according to claim 1, wherein the white board is a circular plate, the circular hole is a circular hole, and the white board is concentric with the circular hole.
4. 4. The stereoscopic cavity-based structure optical target according to claim 1, wherein the white board is disposed at a center position on a side surface of the black case.
5. 5. The stereoscopic cavity-based structure optical target according to claim 1, further comprising a connecting post, wherein the connecting post is located in the black box, one end of the connecting post is fixedly connected with the inner wall of the black box, and the other end of the connecting post is fixedly connected with the white board.
6. 6. The stereoscopic cavity-based structure optical target according to claim 5, further comprising a connection, the connection post being connected with the black box via the connection.
7. 7. The stereoscopic cavity-based optical target according to claim 6, wherein the connecting member is a connecting screw, and a free end of the connecting screw penetrates through the black box body and is in fit connection with a threaded hole formed in the connecting post.
8. 8. The stereoscopic cavity-based optical target according to claim 1, further comprising a coating disposed on an inner wall of the black box for attenuating light.
9. 9. The stereoscopic cavity-based optical target according to claim 8, wherein the coating is a light absorbing layer.
10. 10. The stereoscopic cavity-based structure optical target according to claim 8, wherein the coating is a diffuse reflective layer.

Description

Optical target based on three-dimensional cavity type structure Technical Field The invention relates to the technical field of optical targets, in particular to an optical target based on a three-dimensional cavity structure. Background Industrial camera measurements are essentially quantitative analysis of grey scale images. Ideally, the pixel gray valueIntensity of illumination received therebyThe proportional relation is that: . Wherein. Is a scaling factor. This shows that the gray value directly reflects the number of photons received by the sensor during the exposure time, so that a sufficiently large gray difference between the target and the background is a prerequisite for achieving high accuracy edge positioning. However, in the conventional black-and-white targets, due to the physical characteristics of the materials, the intensity of the white background reflected light is difficult to infinitely increase, and the black region has non-negligible residual reflection due to limited absorbance (usually less than 95%), so that the contrast is limited in theory, is easy to be interfered by ambient stray light, and has a gentle gray gradient at the imaging edge. Disclosure of Invention In view of this, it is necessary to provide an optical target based on a three-dimensional cavity structure, so as to solve the problems that in the conventional black-and-white target, due to the physical characteristics of the material itself, the reflected light intensity of the white background is difficult to be infinitely increased, the black area has non-negligible residual reflection due to the limited absorbance (usually less than 95%), the contrast is limited, the interference of ambient stray light is easy to occur, and the gray gradient of the imaging edge is gentle. The embodiment of the invention provides an optical target based on a three-dimensional cavity type structure, which comprises a black box body and a white plate, wherein a light absorption cavity is formed in the black box body, a round hole is formed in one side surface of the black box body, the white plate is connected with the black box body and is arranged in the round hole, an annular area communicated with the light absorption cavity is formed between the white plate and the black box body, and light rays are incident into the light absorption cavity through the annular area and attenuated in the light absorption cavity so as to form gray level difference between the annular area and the white plate. Further, the black box body is a cube. Further, the white board is a circular board, the round hole is a round hole, and the white board and the round hole are concentrically arranged. Further, the white plate is disposed at a center position on a side surface of the black box. Further, still include the spliced pole, the spliced pole is located in the black box, just the one end of spliced pole with the inner wall fixed connection of black box, the other end of spliced pole with white board fixed connection. Further, the black box comprises a connecting piece, and the connecting column is connected with the black box body through the connecting piece. Further, the connecting piece is a connecting screw, and the free end of the connecting screw penetrates through the black box body and is connected with a threaded hole formed in the connecting column in a matched mode. Further, the black box comprises a coating arranged on the inner wall of the black box body for attenuating light. Further, the coating is a light absorbing layer. Further, the coating is a diffuse reflection layer. Compared with the prior art, light irradiates the optical target, wherein one part of the light irradiates the white board and is reflected, the other part of the light irradiates the side wall of the black box body and is absorbed, and the other part of the light enters the light absorption cavity through the annular area and is attenuated in the light absorption cavity, so that an extremely low gray value which is close to a theoretical black body is formed at the annular area, the boundary between a light spot formed on the white board and the annular area is clear, and a good gray difference is formed between the light spot and the annular area. Drawings Fig. 1 is a schematic structural diagram of an entire optical target based on a three-dimensional cavity structure according to an embodiment of the present invention; FIG. 2 is a cross-sectional view taken along the A-A plane in FIG. 1. Detailed Description The following detailed description of preferred embodiments of the application is made in connection with the accompanying drawings, which form a part hereof, and together with the description of the embodiments of the application, are used to explain the principles of the application and are not intended to limit the scope of the application. As shown in fig. 1, the optical target based on a three-dimensional cavity structure provided by the embodiment of