Optical sensor device and mobile object
The optical sensor device with convex portions on its light-transmitting surface addresses the issue of foreign matter adhesion, ensuring effective light transmission and reducing complexity and costs.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2026-03-12
AI Technical Summary
The presence of foreign matter such as water droplets, snow, ice, mud, or sand on the light-transmitting portion of optical sensor devices causes reflection, scattering, or absorption of light, impairing device function, and existing prevention methods increase complexity and costs.
The optical sensor device incorporates a light-transmitting portion with a plurality of convex portions on its outer surface, where the distance between adjacent convex portions is equal to or less than the wavelength of emitted or received light, preventing foreign matter adhesion.
This design effectively prevents foreign matter from adhering to the light-transmitting portion without affecting light transmission, thereby maintaining device functionality and reducing complexity and costs.
Smart Images

Figure 2026043209000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to an optical sensor device and a moving object. [Background technology]
[0002] An optical sensor device generally contains a light-emitting element that emits light and a light-receiving element that receives light within a housing. For this reason, the housing is provided with a light-transmitting portion that transmits light emitted by the light-emitting element and transmits external light that is received by the light-receiving element. If foreign matter such as water droplets, snow, ice, mud, or sand adheres to this light-transmitting portion, the foreign matter may cause reflection, scattering, or absorption of light, which may impair the function of the optical sensor device.
[0003] For example, the on-vehicle sensor device disclosed in Patent Document 1 has a sensing surface 5a as a light-transmitting portion. The on-vehicle sensor device disclosed in Patent Document 1 is equipped with a foreign matter adhesion prevention device 1 that sprays gas from around the sensing surface 5a to prevent foreign matter from adhering to the sensing surface 5a. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-170964 Summary of the Invention [Problem to be solved by the invention]
[0005] However, when the foreign matter adhesion prevention device 1 is provided as in the on-vehicle sensor device disclosed in Patent Document 1, the configuration of the optical sensor device becomes complex, and the manufacturing and maintenance costs of the optical sensor device increase.
[0006] An object of the present invention is to prevent foreign matter from adhering to the light transmitting portion of an optical sensor device. [Means for solving the problem]
[0007] In order to solve the above problem, an optical sensor device according to one embodiment of the present invention comprises a light-emitting element, a light-receiving element, and a housing that houses the light-emitting element and the light-receiving element, wherein the housing has a light-transmitting portion that transmits light emitted by the light-emitting element to the outside and transmits light from the outside that is received by the light-receiving element, and at least a portion of the outer surface of the light-transmitting portion has a plurality of convex portions, and the distance between adjacent convex portions among the plurality of convex portions is equal to or less than the wavelength of the light emitted by the light-emitting element.
[0008] An optical sensor device according to one embodiment of the present invention comprises a light receiving element and a housing that houses the light receiving element, the housing having a light-transmitting portion for transmitting light from the outside that is received by the light receiving element, at least a portion of the outer surface of the light-transmitting portion having a plurality of convex portions, and the distance between adjacent convex portions among the plurality of convex portions is equal to or less than the wavelength of the light received by the light receiving element.
[0009] A moving body according to one embodiment of the present invention is a moving body on which an optical sensor device is installed, and the partial region faces downward or obliquely downward. [Effects of the Invention]
[0010] According to the present invention, it is possible to prevent foreign matter from adhering to the light transmitting portion of the optical sensor device. [Brief explanation of the drawings]
[0011] [Figure 1] 1 is a cross-sectional view of an optical sensor device 100 according to an embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged view of area A in FIG. [Figure 3] 1 is a diagram illustrating installation of an optical sensor device 100 on a moving body M. FIG. [Figure 4] 1 is a diagram illustrating installation of an optical sensor device 100 on a moving body M. FIG. [Figure 5] 1 is a diagram illustrating installation of an optical sensor device 100 on a moving body M. FIG. DETAILED DESCRIPTION OF THE INVENTION
[0012] <Optical sensor device 100> FIG. 1 is a cross-sectional view of an optical sensor device 100 according to one embodiment of the present invention. The optical sensor device 100 includes a light-emitting element 110, a light-receiving element 120, and a housing 130. The optical sensor device 100 is, for example, a sensor that measures an object to be measured by emitting light from the light-emitting element 110 and receiving the light reflected by the object to be measured with the light-receiving element 120, such as a distance measuring sensor. The optical sensor device 100 is installed, for example, on a moving object M (for example, a vehicle). The optical sensor device 100 may be a device (for example, a camera) that does not include the light-emitting element 110. In this case, the optical sensor device 100 includes the light-receiving element 120 and a housing 130.
[0013] The light emitting element 110 is an element that emits light. The light emitting element 110 emits, for example, infrared light (particularly, near-infrared light (780 nm to 3 μm)). That is, the emission wavelength range of the light emitting element 110 includes infrared light (particularly, near-infrared light (780 nm to 3 μm)).
[0014] The light receiving element 120 is an element that receives light. The light receiving element 120 receives light in the wavelength range of light emitted by the light emitting element 110, for example. In other words, the light receiving wavelength range of the light receiving element 120 includes the light emission wavelength range of the light emitting element 110. When the optical sensor device 100 is a device (for example, a camera), the light receiving wavelength range of the light receiving element 120 includes, for example, visible light and / or infrared light.
[0015] 1, the housing 130 accommodates the light emitting element 110 and the light receiving element 120. The light emitting element 110 and the light receiving element 120 may be mounted on an electronic board 140, and the housing 130 may accommodate the electronic board 140 on which the light emitting element 110 and the light receiving element 120 are mounted.
[0016] The housing 130 has a light-transmitting portion 131. The light-transmitting portion 131 is a portion that transmits light emitted from the light-emitting element 110 to the outside and transmits light from the outside that is received by the light-receiving element 120. The transmittance of the light-transmitting portion 131 is 70% or more in the wavelength region of the light emitted by the light-emitting element 110 (or the light-receiving wavelength region of the light-receiving element 120).
[0017] In this embodiment, at least a partial region (first region 1311) of the outer surface of light transmitting portion 131 has a plurality of convex portions 1312, as shown in Fig. 2. Fig. 2 is an enlarged view of region A in Fig. 1. Region A is a region within first region 1311.
[0018] In this embodiment, the plurality of protrusions prevent adhesion of water droplets, snow, ice, mud, sand, etc. Therefore, in this embodiment, it is possible to prevent adhesion of foreign matter such as water droplets, snow, ice, mud, sand, etc. to first region 1311 of light transmitting portion 131.
[0019] Furthermore, the distance D between adjacent convex portions of the plurality of convex portions 1312 (i.e., the distance between the tops of adjacent convex portions 1312 of the plurality of convex portions 1312) is equal to or less than the wavelength of light emitted by the light emitting element 110. For example, the distance D between adjacent convex portions of the plurality of convex portions 1312 is equal to or less than the wavelength of light with the longest wavelength of light emitted by the light emitting element 110.
[0020] Therefore, in this embodiment, light is not scattered by the multiple protrusions 1312 in the emission wavelength range of the light emitting element 110 or the light receiving wavelength range of the light receiving element 120. As a result, in this embodiment, it is possible to prevent foreign matter such as water droplets, snow, ice, mud, and sand from adhering to the optical sensor device 100 without affecting the measurement.
[0021] In this case, when the optical sensor device 100 is a device (for example, a camera), the distance D between adjacent convex portions of the plurality of convex portions 1312 is equal to or less than the wavelength of light received by the light receiving element 120. For example, the distance D between adjacent convex portions of the plurality of convex portions 1312 is equal to or less than the wavelength of light with the maximum wavelength in the light receiving wavelength range of the light receiving element 120.
[0022] Depending on the grain size, soil is classified into clay (1 μm to 5 μm), silt (5 μm to 75 μm), fine sand (75 μm to 450 μm), coarse sand (450 μm to 2 mm), and gravel (2 mm or more). Clay, which has the smallest grain size of soil, has a grain size of 1 μm to 5 μm. Therefore, it is preferable to set the wavelength of light emitted from the light emitting element 110 to 1 μm or less. By doing so, the distance D between adjacent convex portions 1312 among the multiple convex portions 1312 becomes 1 μm or less. Therefore, by doing so, it is possible to prevent the clay, which has the smallest grain size, from adhering to the surface without affecting the measurement of the optical sensor device 100.
[0023] The shape of the protrusions 1312 includes various shapes. For example, the shape of the protrusions 1312 is a mountain shape or a dome shape. The shape of the protrusions 1312 may be a shape in which the top portions of the protrusions 1312 extend in one direction (a wave shape). Furthermore, the shape of the protrusions 1312 may be a shape in which the top portions of the protrusions 1312 extend in two directions (a lattice shape).
[0024] The plurality of convex portions 1312 of the light transmitting portion 131 may be formed by processing the outer surface of the transparent resin substrate, or by attaching to the outer surface of the transparent resin substrate a sheet having the plurality of convex portions 1312. The plurality of convex portions 1312 of the light transmitting portion 131 may also be formed by coating, printing, vapor deposition, or mechanical surface treatment (roughening).
[0025] Furthermore, it is preferable that the first region 1311 includes a region through which the light emitted by the light-emitting element 110 passes and a region through which the light received by the light-receiving element passes. Generally, reflected light is scattered more than emitted light. Therefore, it is preferable that the first region 1311 be set based on the light-receiving area of the light-receiving element 120. This makes it possible to prevent foreign matter such as water droplets, snow, ice, mud, and sand from adhering to the region through which the light emitted by the light-emitting element 110 passes and the region through which the light received by the light-receiving element passes.
[0026] <Installation on moving object M> When the optical sensor device 100 is installed on a moving body M (for example, a vehicle), the first region 1311 of the light transmitting portion 131 may be oriented downward as shown in Fig. 3. Alternatively, the first region 1311 of the light transmitting portion 131 may be oriented obliquely downward as shown in Figs. 4 and 5. This makes it possible to more effectively prevent foreign matter from adhering to the first region 1311 of the light transmitting portion 131. This improves the ability of foreign matter to fall off from the first region 1311 of the light transmitting portion 131.
[0027] When the first region 1311 of the light-transmitting portion 131 faces diagonally downward, the optical sensor device 100 itself may be installed at an angle to the moving body M, as shown in FIG. 4, or only the light-transmitting portion 131 may be installed at an angle, as shown in FIG. 5.
[0028] The present invention has been described above in terms of preferred embodiments thereof. While the present invention has been described herein with reference to specific examples, various modifications and variations can be made to these examples without departing from the spirit and scope of the present invention as set forth in the claims. [Explanation of symbols]
[0029] 100 Optical sensor device 110 Light-emitting element 120 Photodetector 130 cabinet 131 Light transmitting part 1311 First Area 1312 Convex part
Claims
1. A light-emitting element; A light receiving element; a housing that houses the light emitting element and the light receiving element therein, the housing has a light-transmitting portion for transmitting light emitted by the light-emitting element to the outside and transmitting light from the outside to be received by the light-receiving element, At least a part of the outer surface of the light transmitting portion has a plurality of convex portions, a distance between adjacent ones of the plurality of protrusions is equal to or less than the wavelength of light emitted by the light-emitting element;
2. The optical sensor device according to claim 1 , wherein the light emitted by the light-emitting element is infrared light.
3. The optical sensor device according to claim 2 , wherein the light emitted by the light-emitting element is near-infrared light.
4. 4. The optical sensor device according to claim 3, wherein the wavelength of light emitted by said light emitting element is 1 [mu]m or less.
5. 2. The optical sensor device according to claim 1, wherein the transmittance of the light transmitting portion is 70% or more in the wavelength region of light emitted by the light emitting element.
6. The optical sensor device according to claim 1 , wherein the area of the partial region is set to include a region through which light emitted by the light-emitting element passes and a region through which light received by the light-receiving element passes.
7. The optical sensor device according to claim 6 , wherein the area of the partial region is set based on a light-receiving area of the light-receiving element.
8. A light receiving element; a housing that houses the light receiving element therein, the housing has a light-transmitting portion for transmitting external light received by the light-receiving element, At least a part of the outer surface of the light transmitting portion has a plurality of convex portions, an optical sensor device, wherein a distance between adjacent ones of the plurality of convex portions is equal to or less than a wavelength of light received by the light receiving element;
9. A moving body having the optical sensor device according to any one of claims 1 to 8 installed therein, The moving body, wherein the partial region faces diagonally downward.
Citation Information
Patent Citations
Foreign matter adhesion preventive device and on-vehicle sensor device
JP2015170964A