A high weather-resistant reflective film for use in lidar rotating mirrors

Abstract

This utility model relates to the field of reflective film technology, specifically to a high weather-resistant reflective film for use in a lidar rotating mirror. It includes a Cr film layer for deposition on the rotating mirror, upon which a first Y₂O₃ film layer, an Ag film layer, a second Y₂O₃ film layer, a first SiO₂ film layer, a first TiO₂ film layer, a second SiO₂ film layer, a second TiO₂ film layer, a third SiO₂ film layer, and an anti-fingerprint (AF) film layer are sequentially deposited. This utility model has a simple structure, ultra-high reflectivity and high corrosion resistance, achieving a reflectivity of >99% at 905nm wavelength, and passing a 120-hour accelerated aging test under constant humidity and heat (85℃, 85%RH).

Description

Technical Field

[0001] This utility model relates to the field of reflective film technology, specifically to a high weather-resistant reflective film applied to a rotating reflector of a lidar system. Background Technology

[0002] LiDAR determines distance by measuring the time and phase differences of laser signals and uses Doppler imaging technology to create a clear 3D image of the target. LiDAR emits and receives laser beams, analyzes the time it takes for the laser to return after encountering a target object, calculates the relative distance to the target, and uses the 3D coordinates, reflectivity, and texture information of numerous dense points on the target object's surface collected during this process to derive a 3D model of the target and related data, creating a 3D point cloud map and drawing an environmental map to achieve environmental perception. The rotating mirror in a LiDAR system is mainly used to achieve the scanning function of the laser beam. By rotating the mirror surface at high speed, the laser is directionally reflected in different directions, thus covering an all-around perception of the target area. The optical surface of the rotating mirror needs to achieve high reflectivity to the LiDAR's operating wavelength of 905nm to enhance signal strength and improve the LiDAR's sensing capability.

[0003] In the industry, the rotating reflector of lidar is made of PC injection molding, and then a vacuum-plated silver reflective film is applied to the optical surface. The silver reflective film typically has a reflectivity exceeding 97%. However, moisture can easily penetrate the PC and enter the reflective film layer, oxidizing and corroding the metallic silver. This makes it impossible to meet the requirements of conventional constant humidity and heat (85℃, 85%RH, 48H) accelerated aging tests. The oxidation and corrosion of the metallic silver leads to a significant decrease in the reflectivity of the rotating reflector, affecting its service life. Therefore, improving the reflectivity and corrosion resistance of the rotating reflector film is of great significance to the performance of lidar. Utility Model Content

[0004] The purpose of this invention is to provide a highly weather-resistant reflective film for use in LiDAR rotating mirrors.

[0005] This utility model provides the following technical solution:

[0006] This invention proposes a high weather-resistant reflective film for use in a lidar rotating mirror, comprising a Cr film layer for depositing on the rotating mirror, wherein a first Y2O3 film layer, an Ag film layer, a second Y2O3 film layer, a first SiO2 film layer, a first TiO2 film layer, a second SiO2 film layer, a second TiO2 film layer, a third SiO2 film layer, and an anti-fingerprint AF film layer are sequentially deposited on the Cr film layer.

[0007] Furthermore, the thickness of the Cr film is 20±0.3nm, the thickness of the first Y2O3 film is 30±0.3nm, the thickness of the Ag film is 100±0.3nm, the thickness of the second Y2O3 film is 30±0.3nm, the thickness of the first SiO2 film is 100.34±0.3nm, the thickness of the first TiO2 film is 95.78±0.3nm, the thickness of the second SiO2 film is 155.71±0.3nm, the thickness of the second TiO2 film is 95.79±0.3nm, the thickness of the third SiO2 film is 30±0.3nm, and the thickness of the anti-fingerprint AF film is 10±0.3nm.

[0008] Furthermore, at a test wavelength of 905nm and a light incident angle of 0°, the refractive indices of the first and second Y2O3 films are both 1.75-1.85; the refractive indices of the first and second TiO2 films are both 2.2-2.59; the refractive indices of the first, second, and third SiO2 films are all 1.43-1.47; and the refractive index of the anti-fingerprint AF film is 1.48-1.5.

[0009] Furthermore, at a test wavelength of 905nm and a light incident angle of 0°, the refractive indices of the first Y2O3 film and the second Y2O3 film are both 1.79; the refractive indices of the first TiO2 film and the second TiO2 film are both 2.39; the refractive indices of the first SiO2 film, the second SiO2 film, and the third SiO2 film are all 1.46; and the refractive index of the anti-fingerprint AF film is 1.49.

[0010] Compared with the prior art, this utility model has a simple structure, ultra-high reflectivity and high corrosion resistance, and can achieve a reflectivity of >99% at a wavelength of 905nm. It also passes the 120H test of constant damp heat (85℃, 85%RH) accelerated aging test. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the connection relationship between the various membrane layers of this utility model (the thickness of the membrane layers is not shown in this diagram).

[0012] Figure 2 This is a diagram illustrating the reflective effect of this utility model.

[0013] 00-Rotating reflector; 1-Cr film; 2-First Y2O3 film; 3-Ag film; 4-Second Y2O3 film; 5-First SiO2 film; 6-First TiO2 film; 7-Second SiO2 film; 8-Second TiO2 film; 9-Third SiO2 film; 10-Anti-fingerprint AF film. Detailed Implementation

[0014] The following is in conjunction with the appendix Figure 1 The present invention will be further described below.

[0015] In one embodiment of this utility model, a high weather-resistant reflective film for use in a lidar rotating mirror is proposed, comprising a Cr film layer 1 for depositing on the rotating mirror 00, wherein a first Y2O3 film layer 2, an Ag film layer 3, a second Y2O3 film layer 4, a first SiO2 film layer 5, a first TiO2 film layer 6, a second SiO2 film layer 7, a second TiO2 film layer 8, a third SiO2 film layer 9, and an anti-fingerprint AF film layer 10 are sequentially deposited on the Cr film layer 1; wherein the Cr film layer is reinforced The bonding force between the reflective film and the rotating mirror 00 is enhanced. The Y2O3 film layer improves the corrosion resistance of the silver layer and prevents water vapor intrusion and corrosion. The Ag film layer achieves high reflectivity of the rotating mirror. The SiO2 and TiO2 film layers further enhance the reflectivity of the Ag film layer. The anti-fingerprint AF film layer improves scratch resistance. In practical applications, this invention can achieve a reflectivity of >99% at a wavelength of 905nm and improve corrosion resistance. It can pass the 120H test in the constant damp heat (85℃, 85%RH) accelerated aging test.

[0016] In one embodiment of this utility model, the thickness of the Cr film layer 1 is 20±0.3nm, the thickness of the first Y2O3 film layer 2 is 30±0.3nm, the thickness of the Ag film layer 3 is 100±0.3nm, the thickness of the second Y2O3 film layer 4 is 30±0.3nm, the thickness of the first SiO2 film layer 5 is 100.34±0.3nm, the thickness of the first TiO2 film layer 6 is 95.78±0.3nm, the thickness of the second SiO2 film layer 7 is 155.71±0.3nm, the thickness of the second TiO2 film layer 8 is 95.79±0.3nm, the thickness of the third SiO2 film layer 9 is 30±0.3nm, and the thickness of the anti-fingerprint AF film layer 10 is 10±0.3nm.

[0017] In one embodiment of this utility model, at a test wavelength of 905nm and a light incident angle of 0°, the refractive indices of the first Y2O3 film layer 3 and the second Y2O3 film layer 4 are both 1.75-1.85; the refractive indices of the first TiO2 film layer 6 and the second TiO2 film layer 8 are both 2.2-2.59; the refractive indices of the first SiO2 film layer 5, the second SiO2 film layer 7, and the third SiO2 film layer 9 are all 1.43-1.47; and the refractive index of the anti-fingerprint AF film layer 10 is 1.48-1.5.

[0018] In one embodiment of this utility model, at a test wavelength of 905nm and a light incident angle of 0°, the refractive indices of the first Y2O3 film layer 3 and the second Y2O3 film layer 4 are both 1.79; the refractive indices of the first TiO2 film layer 6 and the second TiO2 film layer 8 are both 2.39; the refractive indices of the first SiO2 film layer 5, the second SiO2 film layer 7, and the third SiO2 film layer 9 are all 1.46; and the refractive index of the anti-fingerprint AF film layer is 1.49.

[0019] In practical applications, the rotating mirror is cleaned using an ultrasonic cleaner, then baked at 80±5℃ for 1 hour. Afterward, the rotating mirror is placed in a vacuum electron beam evaporation coating machine (vacuum degree 3×10⁻⁶ during film deposition). -3 (Pa, vacuum chamber ambient heating temperature 100℃), a Cr film layer (deposition rate 0.3nm / s), a first Y2O3 film layer (deposition rate 0.3nm / s), an Ag film layer (deposition rate 2nm / s), a second Y2O3 film layer (deposition rate 0.3nm / s), a first SiO2 film layer (deposition rate 0.8nm / s), a first TiO2 film layer (deposition rate 0.4nm / s), a second SiO2 film layer (deposition rate 0.8nm / s), a second TiO2 film layer (deposition rate 0.4nm / s), a third SiO2 film layer (deposition rate 0.8nm / s), and an anti-fingerprint AF film layer (deposition rate 0.8nm / s) are sequentially deposited on the surface of the rotating mirror. This invention can pass a 120-hour accelerated aging test under constant humidity and heat (85℃, 85%RH), improving the service life of the rotating mirror. Figure 2 The result shows that it can achieve an ultra-high reflectivity of >99% at a wavelength of 905nm, thus improving the sensing performance of lidar.

[0020] The embodiments of this utility model are given for the purpose of illustration and description. Although embodiments of this utility model have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this utility model. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this utility model.

Claims

1. A high weather-resistant reflective film for use in a rotating reflector of a lidar system, characterized in that: It includes a Cr film layer for depositing on the rotating mirror, wherein a first Y2O3 film layer, an Ag film layer, a second Y2O3 film layer, a first SiO2 film layer, a first TiO2 film layer, a second SiO2 film layer, a second TiO2 film layer, a third SiO2 film layer, and an anti-fingerprint AF film layer are sequentially deposited on the Cr film layer.

2. The high weather-resistant reflective film for use in a rotating reflector of a lidar system according to claim 1, characterized in that: The thickness of the Cr film is 20±0.3nm, the thickness of the first Y2O3 film is 30±0.3nm, the thickness of the Ag film is 100±0.3nm, the thickness of the second Y2O3 film is 30±0.3nm, the thickness of the first SiO2 film is 100.34±0.3nm, the thickness of the first TiO2 film is 95.78±0.3nm, the thickness of the second SiO2 film is 155.71±0.3nm, the thickness of the second TiO2 film is 95.79±0.3nm, the thickness of the third SiO2 film is 30±0.3nm, and the thickness of the anti-fingerprint AF film is 10±0.3nm.

3. The high weather-resistant reflective film for use in a rotating reflector of a lidar system according to claim 1, characterized in that: At a test wavelength of 905nm and a light incident angle of 0°, the refractive indices of the first and second Y2O3 films are both 1.75-1.85; the refractive indices of the first and second TiO2 films are both 2.2-2.59; the refractive indices of the first, second, and third SiO2 films are all 1.43-1.47; and the refractive index of the anti-fingerprint AF film is 1.48-1.

5.

4. The high weather-resistant reflective film for use in a rotating reflector of a lidar system according to claim 3, characterized in that: At a test wavelength of 905nm and a light incident angle of 0°, the refractive indices of the first and second Y2O3 films are both 1.79; the refractive indices of the first and second TiO2 films are both 2.39; the refractive indices of the first, second, and third SiO2 films are all 1.46; and the refractive index of the anti-fingerprint AF film is 1.49.

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