Reflection element, optical collimation assembly, manufacturing method thereof, and structured light projection device

Abstract

The present invention provides a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device. The reflection element includes a reflection main body and a molded body. The reflection main body is made of a solid light-transmitting medium. The reflection element has at least one reflection surface, an incident surface, and an exit surface. The molded body is molded outside the reflection surface so that a light beam enters the reflection element from the incident surface, is reflected at least once by the reflection surface, and then exits from the exit surface.

Description

Technical Field

[0001] The present invention relates to a structured light projection device, and more particularly to a reflection element, an optical collimation component, a manufacturing method thereof, and a structured light projection device, so as to reduce process requirements and improve the yield rate. Background Art

[0002] There are many technical solutions for realizing depth imaging. The mainstream solutions include the binocular solution, the TOF solution, and the structured light solution. The binocular solution has a relatively low cost, but the biggest problem is that the implementation algorithm requires high computing resources, resulting in poor real-time performance, and it is basically related to the resolution and detection accuracy. That is to say, the higher the resolution and the higher the required accuracy, the more complex the calculation. At the same time, the pure binocular solution is affected by light and the texture properties of objects.

[0003] The structured light solution is proposed to solve the complexity and robustness problems of the binocular matching algorithm. The structured light method does not depend on the color and texture of the object itself. It uses the method of actively projecting a known pattern to achieve fast and robust matching of feature points, which can achieve relatively high accuracy and greatly expand the applicable range. With the gradual development and improvement of the structured light technology, structured light depth imaging is becoming more and more popular in the market. In particular, its application in mobile terminals has attracted the attention of many mobile manufacturers. For example, the front camera module of the IphoneX adopts the speckle structured light technology for face recognition and unlocking.

[0004] The basic working process of a structured light depth camera is that the structured light is projected onto the surface of the object to be measured and then modulated by the height of the object to be measured. The modulated structured light is collected by the imaging system and transmitted to a computer for analysis and calculation, and then the three-dimensional surface shape data of the object to be measured can be obtained. The projection device used in the existing structured light depth camera includes a light emitter, a collimating mirror, and an optical diffraction element, wherein the collimating mirror is disposed between the light emitter and the optical diffraction element. The light emitted by the light emitter is collimated by the collimating mirror and then projected onto the surface of the spatial target after being diffracted or replicated by the optical diffraction element.

[0005] However, as the terminal becomes thinner and thinner, the demand for cameras is gradually developing towards miniaturization. Among them, how to reduce the height dimension of the camera has become an inevitable problem. Since it is necessary to ensure the back focal length or focal length during the module design or operation, reducing the height has become a difficult problem. To solve this problem, in many modules, an optical reflection element is added to reduce the module size while keeping the optical path unchanged.

[0006] For example, in the patent with the publication number US20170075205A1 and the title "Integrated Lightpipe for Optical Projection", an integrated lightpipe is disclosed. A reflection space is formed by two relatively parallel light-transmitting substrates and two relatively parallel reflecting plates. The opposite surfaces of the two reflecting plates are provided with reflecting surfaces that are parallel to each other and can reflect light, and each reflecting surface is inclined with respect to the light-transmitting substrate. Each light-transmitting substrate is provided with opposite optical lenses on both sides of a preset area. Light enters from the two optical lenses on the incident side, is reflected by the opposite and parallel reflecting surfaces, and then exits from the two optical lenses on the exit side to achieve the purpose of being collimated.

[0007] In this solution, the two reflecting plates need to be parallel to ensure that the opposite reflecting surfaces are parallel, so that the light after reflection is parallel to the light before reflection and there is no scattering during the reflection process. However, ensuring the parallelism of the two reflecting plates and the two reflecting surfaces requires high manufacturing precision. Once the reflecting surfaces are not parallel, the sensitive light will deflect. In the patent with the publication number US20170075205A1, a solution of using spacer elements to space the two reflecting plates is disclosed. However, even if the two surfaces of the spacer elements that are in contact with the two reflecting plates respectively are parallel, the two reflecting plates are prone to errors during the assembly process with the spacer elements, resulting in non-parallelism of the two reflecting plates. For example, the fixing glue between the spacer element and the reflecting plate is uneven, or the surface of the reflecting plate in contact with the spacer element is not flat, etc. That is to say, this solution has high requirements for manufacturing technology, is likely to cause the product to not meet the requirements, has a low product yield, and is not suitable for mass production. Especially for equipment with high requirements for optical precision, this production solution is not appropriate.

[0008] In addition, since the center of this integrated lightpipe is a cavity, the overall stability can only be maintained by the connection between the two light-transmitting substrates and the two reflecting plates, and the parallelism between the reflecting plates. Once it is impacted or subjected to an impact force, the connection between the light-transmitting substrate and the reflecting plate is easily damaged. Not only is the whole likely to fall apart, but the reflecting plates are also prone to move and generate errors, and the whole may even fall apart. Summary of the Invention

[0009] An object of the present invention is to provide a reflecting element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device. The optical collimation assembly utilizes the invariant optical path of the reflecting element and has a relatively small size, especially a relatively small height dimension, which is suitable for the current development of miniaturization requirements.

[0010] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the optical collimation assembly is a solid structure with high structural strength and is not easily disassembled when subjected to an impact force.

[0011] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the optical collimation assembly has high structural strength, and in particular, the possibility that two opposite and parallel reflecting surfaces do not move or deform due to an impact is reduced, ensuring accuracy.

[0012] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the optical collimation assembly is structurally compact and suitable for devices with high optical precision requirements.

[0013] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the manufacturing method of the optical collimation assembly has low requirements for manufacturing processes and a high yield rate.

[0014] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the manufacturing method of the optical collimation assembly forms reflecting surfaces by using a first surface and a second surface of a light-transmitting medium, and the first surface and the second surface can be made parallel by mature existing processes such as grinding, with low requirements for manufacturing processes.

[0015] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the manufacturing method of the optical collimation assembly forms reflecting surfaces by using a first surface and a second surface of a light-transmitting medium, and the first surface and the second surface can be made parallel by mature existing processes such as grinding to ensure accuracy, thereby improving the product yield rate.

[0016] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein an optical lens can be directly mounted on a preset area of the incident surface and the exit surface of the optical collimation assembly, or mounted by using a splicing process to achieve the collimation purpose. That is to say, those skilled in the art can select a suitable mounting process according to the actual situation, which is convenient for production.

[0017] Another object of the present invention is to provide a reflection element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the reflecting surface of the optical collimation assembly is implemented as a free-form surface, and the beam is directly collimated by the free-form surface.

[0018] Another object of the present invention is to provide a reflective element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the optical diffraction element of the structured light projection device has a collimation function, and after the light beam is collimated by the optical collimation assembly, it can be further collimated by the optical diffraction element, thereby improving the collimation effect.

[0019] Another object of the present invention is to provide a reflective element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the optical diffraction element of the structured light projection device has a collimation function, and it can also reduce the requirements for the optical lens surface type and curvature of the optical collimation assembly, thereby reducing the processing difficulty.

[0020] Another object of the present invention is to provide a reflective element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein a detection circuit is disposed on the surface of the optical diffraction element, so as to detect by detecting the conduction of the detection circuit, ensure the integrity of the structure of the optical diffraction element, and avoid damage to the human eye caused by the projection ability after the optical diffraction element is damaged.

[0021] Another object of the present invention is to provide a reflective element, an optical collimation assembly, a manufacturing method thereof, and a structured light projection device, wherein the reflective element adopts a molding process to form a side wall, so as to facilitate the conduction of the detection circuit and the circuit board through the LDS process (Laser Direct Structuring), without an external circuit structure, reducing the process difficulty and reducing the overall volume of the projection module.

[0022] To achieve at least one of the above objects of the present invention, according to one aspect of the present invention, the present invention further provides a reflective element, including:

[0023] A reflective main body and a molded body, wherein the reflective main body is made of a solid light-transmitting medium, the reflective main body has at least one reflective surface, an incident surface, and an exit surface, and the molded body is molded outside the reflective surface, so that a light beam enters the reflective element from the incident surface, is reflected by the reflective surface at least once, and then exits from the exit surface.

[0024] According to an embodiment of the present invention, the reflective surface is formed by covering a reflective material on the surface of the light-transmitting medium.

[0025] According to an embodiment of the present invention, the reflective element has two reflective surfaces, wherein the two reflective surfaces are opposite and parallel, and are inclined relative to the incident surface and the exit surface, so that a light beam enters the reflective element from the incident surface, is reflected by the reflective surface at least twice, and then exits from the exit surface, so that the incident light beam and the exit light beam are parallel.

[0026] According to an embodiment of the present invention, the incident surface and the exit surface are opposite and parallel, and the cross-section of the reflecting element is a parallelogram.

[0027] According to an embodiment of the present invention, the two reflecting surfaces are implemented as flat surfaces.

[0028] According to an embodiment of the present invention, the two reflecting surfaces are implemented as free-form surfaces.

[0029] According to an embodiment of the present invention, the turning angle of the free-form surface is 50° to 75°.

[0030] According to an embodiment of the present invention, the turning angle of the light beam on the free-form surface is 60° to 150°.

[0031] According to an embodiment of the present invention, the turning angle of the light beam on the free-form surface is 90° to 120°.

[0032] In another aspect of the present invention, the present invention further provides an optical collimation assembly for a structured light projection device, including:

[0033] Any one of the reflecting elements as described above; and

[0034] At least one optical lens, wherein the optical lens is installed in the preset area of the incident surface or / and the exit surface to achieve collimation.

[0035] According to an embodiment of the present invention, the optical collimation assembly further includes at least one transparent substrate, wherein the transparent substrate is made of a light-transmitting material, the transparent substrate is attached to the surface of the incident surface or / and the exit surface, and the optical lens is attached to the surface of the transparent substrate corresponding to the preset area of the incident surface or / and the exit surface.

[0036] In another aspect of the present invention, the present invention further provides a structured light projection device, including:

[0037] A projection unit for emitting a light beam;

[0038] Any one of the optical collimation assemblies as described above, wherein the optical collimation assembly collimates the light beam emitted by the projection unit; and

[0039] An optical diffraction element, wherein the light beam emitted by the projection unit is collimated by the optical collimation assembly and then diffracted or replicated by the optical diffraction element and projected onto the surface of a spatial target.

[0040] According to an embodiment of the present invention, the optical diffraction element includes a collimating portion and a diffraction portion, wherein the diffraction portion is disposed on the light-emitting side of the collimating portion, so that the light beam collimated by the optical collimation assembly is further collimated by the collimating portion and then reaches the spatial target through the diffraction portion.

[0041] According to an embodiment of the present invention, the structured light projection device further includes a circuit board and a detection circuit, wherein the projection unit is disposed on the circuit board and electrically connected to the circuit board, and the detection circuit is disposed on the surface of the optical diffraction element and electrically connected to the circuit board for detecting whether the optical diffraction element is intact.

[0042] According to an embodiment of the present invention, the detection circuit is implemented as ITO and is plated on the surface of the optical diffraction element.

[0043] According to an embodiment of the present invention, the structured light projection device further includes a conduction circuit, wherein the conduction circuit electrically connects the detection circuit and the circuit board, and the conduction circuit is formed on the surface of the molded body by adopting an LDS process.

[0044] According to an embodiment of the present invention, the structured light projection device further includes a conduction circuit, wherein the conduction circuit electrically connects the detection circuit and the circuit board, and the conduction circuit is wrapped by the molded body.

[0045] In another aspect of the present invention, the present invention further provides a method for manufacturing an optical collimation assembly for a structured light projection device, including:

[0046] (a) forming a first reflecting surface of the light-transmitting medium and a second reflecting surface of the light-transmitting medium on opposite and parallel first and second surfaces of a solid light-transmitting medium;

[0047] a first reflecting surface and a second reflecting surface of the light-transmitting medium;

[0048] (b) forming a molded layer that wraps the light-transmitting medium having the first reflecting surface of the light-transmitting medium and the second reflecting surface of the light-transmitting medium, wherein the molded layer is made of an opaque material;

[0049] of the light-transmitting medium, wherein the molded layer is made of an opaque material;

[0050] (c) cutting the light-transmitting medium with the molded layer at a preset interval to form a plurality of light-transmitting single strips; and

[0051] (d) Arrange the light-transmitting single strips in a preset direction, and cut the arranged light-transmitting single strips along a preset cutting line to form a plurality of reflection elements each having an incident surface and an exit surface, wherein the extending direction of the light-transmitting single strip and the extending direction of the cutting line form a preset included angle, so that a light beam enters the reflection element from the incident surface, and after being reflected by the reflection element at least once, exits from the exit surface.

[0052] According to an embodiment of the present invention, in step (a), the first reflective surface of the light-transmitting medium and the second reflective surface of the light-transmitting medium are formed by covering the first surface and the second surface with a material having a light-reflecting property.

[0053] According to an embodiment of the present invention, before step (d), the method for manufacturing the optical collimation assembly further includes:

[0054] (e) Process the cut surface of the light-transmitting single strip to form an anti-stray light surface to prevent stray light from entering.

[0055] According to an embodiment of the present invention, in step (e), the anti-stray light surface is formed by roughening the cut surface.

[0056] According to an embodiment of the present invention, in step (e), the anti-stray light surface is formed by covering the surface of the cut surface with a light-shielding material.

[0057] According to an embodiment of the present invention, in step (d), the light-transmitting single strip extends in the horizontal direction, and the preset cutting direction forms a preset included angle with the extending direction of the light-transmitting single strip, and the light-transmitting single strip is cut obliquely.

[0058] According to an embodiment of the present invention, in step (d), the light-transmitting single strip is placed obliquely, and the preset cutting direction extends in the horizontal direction.

[0059] According to an embodiment of the present invention, step (d) further includes the steps of:

[0060] (d.1) Arrange the light-transmitting single strips on a substrate in a preset direction; and

[0061] (d.2) Cut the light-transmitting single strips and the substrate along a preset cutting line to form a plurality of reflection element strips, wherein the extending direction of the light-transmitting single strip and the extending direction of the cutting line form a preset included angle, and the reflection element strip includes a substrate strip and a plurality of the reflection elements each having the incident surface and the exit surface arranged on the substrate strip.

[0062] According to an embodiment of the present invention, the method for manufacturing the optical collimation assembly further includes:

[0063] (e) Mount the optical lenses one by one on the preset areas of the incident surface or the exit surface.

[0064] According to an embodiment of the present invention, the method for manufacturing the optical collimation assembly further includes:

[0065] (f) Arrange the reflective element strips according to the spacing between adjacent rows of the optical lenses in an optical lens mosaic, wherein the arrangement of the optical lenses in the optical lens mosaic corresponds to the arrangement of the reflective elements in the reflective element strips;

[0066] (g) Attach the light-transmitting substrate of the optical lens mosaic to the incident surface or the exit surface of the reflective elements in the reflective element strips, wherein the optical lenses correspond to the preset areas of the incident surface or the exit surface.

[0067] According to an embodiment of the present invention, the method for manufacturing the optical collimation assembly further includes:

[0068] (h) Remove the substrate strips of the reflective element strips.

[0069] According to an embodiment of the present invention, the method for manufacturing the optical collimation assembly further includes:

[0070] (i) Divide the assembled optical lens mosaic and the reflective element strips to form a plurality of the optical collimation assemblies.

[0071] According to an embodiment of the present invention, in the step (d), the light-transmitting single strip is cut twice, and the two preset cutting directions are perpendicular, so that the incident surface and the exit surface of the formed reflective element are perpendicular, so that the light beam enters the reflective element from the incident surface, and after being reflected by the reflective element once, it exits from the exit surface.

[0072] According to an embodiment of the present invention, the first surface and the second surface in the step (a) are opposite and parallel free-form surfaces, wherein the incident surface and the exit surface formed after cutting in the step (d) are corresponding free-form surfaces, and the turning angle of the free-form surfaces of the incident surface and the exit surface is 50° to 75°.

[0073] According to an embodiment of the present invention, in the step (d.1), the light-transmitting single strips are arranged on the substrate in a manner that their cutting surfaces are attached to the substrate. Description of the Drawings

[0074] Figure 1 is a perspective view of a light-transmitting medium of a method for manufacturing an optical collimation assembly according to an embodiment of the present invention.

[0075] Figure 2AA process diagram of forming a first reflecting surface and a second reflecting surface of a light-transmitting medium in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0076] Figure 2B Another process diagram of forming a first reflecting surface and a second reflecting surface of a light-transmitting medium in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0077] Figure 2C A perspective view of a light-transmitting medium after forming a first reflecting surface and a second reflecting surface of the light-transmitting medium in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0078] Figure 2D A cross-sectional view of a light-transmitting medium after forming a first reflecting surface and a second reflecting surface of another light-transmitting medium in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0079] Figure 3A A cross-sectional view of a light-transmitting medium after molding in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0080] Figure 3B A perspective view of a light-transmitting medium after molding in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0081] Figure 4 A cutting schematic diagram of a light-transmitting medium after molding in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0082] Figure 5 A schematic diagram of a single light-transmitting strip after anti-stray light treatment on the cutting surface in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0083] Figure 6A and Figure 6B A schematic diagram of the arrangement and cutting method of single light-transmitting strips in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0084] Figure 6C A three-dimensional view of a reflecting element obtained by a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0085] Figure 6D A cross-sectional view of the above-mentioned reflecting element obtained by a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0086] Figure 7 An installation method of a light-transmitting element in a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0087] Figure 8 It is a flowchart of a method for manufacturing an optical collimation component according to an embodiment of the present invention.

[0088] Figure 9 It is a schematic diagram of the arrangement and cutting method of a single light-transmitting strip for the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0089] Figure 10 It is according to Figure 9 A cross-sectional view after rotation of the reflective element strip obtained by cutting according to the method shown.

[0090] Figure 11A It is a top view of an optical lens layout for the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0091] Figure 11B It is a side view of an optical lens layout for the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0092] Figure 12 It is an assembly diagram of an optical lens layout and a single light-transmitting strip for the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0093] Figure 13 It is according to Figure 12 A cross-sectional view of the reflective element obtained by cutting after assembly.

[0094] Figure 14A It is a schematic diagram of another arrangement and cutting method of a single light-transmitting strip for the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0095] Figure 14B It is another three-dimensional view of a reflective element obtained by the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0096] Figure 15 It is another installation flowchart of a light-transmitting element for the method of manufacturing an optical collimation component according to an embodiment of the present invention.

[0097] Figure 16 It is a cross-sectional view of an optical collimation component according to an embodiment of the present invention.

[0098] Figure 17 It is a cross-sectional view of an optical collimation component according to another embodiment of the present invention.

[0099] Figure 18A It is a cross-sectional view of an optical collimation component according to another embodiment of the present invention.

[0100] Figure 18B It is a cross-sectional view of an optical collimation component according to another embodiment of the present invention.

[0101] Figure 19 A cross-sectional view of an optical collimation assembly according to another embodiment of the present invention.

[0102] Figure 20 A cross-sectional view of an optical collimation assembly according to another embodiment of the present invention.

[0103] Figure 21 A schematic diagram of a cut and molded body of a reflection element of an optical collimation assembly according to an embodiment of the present invention.

[0104] Figure 22 A cross-sectional view of an optical collimation assembly according to an embodiment of the present invention.

[0105] Figure 23 A schematic diagram of a structured light projection device according to an embodiment of the present invention.

[0106] Figure 24 A schematic diagram of a structured light projection device according to another embodiment of the present invention.

[0107] Figure 25 A schematic diagram of a structured light projection device according to another embodiment of the present invention.

[0108] Figure 26 A schematic diagram of a structured light projection device according to another embodiment of the present invention.

[0109] Figure 27 A schematic diagram of a structured light projection device according to another embodiment of the present invention.

[0110] Figure 28 A top view schematic diagram of a structured light projection device according to another embodiment of the present invention. Detailed implementation manners

[0111] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments in the following description are only examples, and those skilled in the art can think of other obvious variations. The basic principles defined in the following description of the present invention can be applied to other implementation manners, variant schemes, improvement schemes, equivalent schemes, and other technical schemes without departing from the spirit and scope of the present invention.

[0112] Those skilled in the art should understand that in the disclosure of the present invention, the orientation or positional relationships indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limiting the present invention.

[0113] It can be understood that the term "one" should be understood as "at least one" or "one or more". That is, in one embodiment, the number of an element can be one, while in other embodiments, the number of this element can be multiple. The term "one" should not be construed as a limitation on the quantity.

[0114] As Figures 1 to 15 shown, an optical collimation assembly for a structured light projection device and a manufacturing method thereof according to the present invention are described. When the optical collimation assembly 10 utilizes a reflection element with an unchanged optical path, it has a relatively small size, especially a relatively small height dimension, and is suitable for the current development of miniaturization requirements. At the same time, the optical collimation assembly is a solid structure with high structural strength, and it is not easily disassembled, displaced, or deformed when subjected to an impact force. The manufacturing method of the optical collimation assembly is used to produce the optical collimation assembly 10, and has low requirements for manufacturing processes and a high product yield.

[0115] As Figure 8 shown, it is a flowchart of the manufacturing method of the optical collimation assembly according to the present invention.

[0116] Step 101: Provide a light-transmitting medium 100, wherein the first surface 110 and the second surface 120 of the light-transmitting medium 100 are opposite and parallel.

[0117] As Figure 1 shown, the light-transmitting medium 100 can be a solid transparent medium such as transparent glass, and the present invention is not limited thereto. The distance D between the first surface and the second surface is not restricted, and those skilled in the art can design it according to requirements. The technology for forming a light-transmitting medium with opposite parallel surfaces is currently very mature. Taking glass as an example, it can be formed by a polishing process, or by using a mold during manufacturing, etc., which will not be elaborated here. Preferably, the light-transmitting medium 100 has a refractive index greater than 1.

[0118] Step 102: Form a first reflecting surface 130 of the light-transmitting medium and a second reflecting surface 140 of the light-transmitting medium on the first surface 110 and the second surface 120 respectively.

[0119] As Figures 2A to 2DAs shown, the first reflective surface 130 of the light-transmitting medium and the second reflective surface 140 of the light-transmitting medium can be formed by covering the surfaces of the first surface 110 and the second surface 120 with a material having a light-reflecting property through sputtering, evaporation, or the like. The first reflective surface 130 of the light-transmitting medium and the second reflective surface 140 of the light-transmitting medium are the surfaces where the light-reflecting material contacts the light-transmitting medium 100.

[0120] Since the first surface 110 and the second surface 120 are opposite and parallel to each other, the first reflective surface 130 of the light-transmitting medium and the second reflective surface 140 of the light-transmitting medium are also opposite and parallel to each other. At this time, the first reflective surface 130 of the light-transmitting medium and the second reflective surface 140 of the light-transmitting medium are formed by adhering to the light-transmitting medium 100, which reduces the requirements for the manufacturing process. There is no need to additionally provide a substrate to ensure the parallelism between the reflective surfaces, and it also avoids errors caused by additional assembly steps.

[0121] Specifically, during the implementation of step 102, it can be that the first surface 110 and the second surface 120 are coated successively (as shown in Figure 2A ), or it can be that the first surface 110 and the second surface 120 are coated simultaneously (as shown in Figure 2B ), and the present invention does not limit this. Alternatively, each surface of the light-transmitting medium 100 can be coated (as shown in Figure 2D ).

[0122] Step 103: Form a molding layer 200 that wraps the light-transmitting medium 100 having the first reflective surface 130 of the light-transmitting medium and the second reflective surface 140 of the light-transmitting medium.

[0123] The molding layer 200 is formed on the surface of the light-transmitting medium 100 through processes such as molding, pressing, or injection molding. The molding layer 200 is made of an opaque material, so that the reflective element 11 of the subsequent formed optical collimation assembly 10 can shield unnecessary stray light, as shown in Figure 3A and Figure 3B .

[0124] Step 104: Cut the light-transmitting medium 100 with the molding layer 200 at a preset interval to form a plurality of light-transmitting single strips 150.

[0125] As shown in Figure 4As shown, it is the implementation process of step 104. It can be known that since the light-transmitting medium 100 has the first reflecting surface 130 and the second reflecting surface 140 of the light-transmitting medium that are opposite and parallel, after cutting, the obtained light-transmitting single strip 150 should also have a first reflecting surface 152 of the light-transmitting single strip and a second reflecting surface 153 of the light-transmitting single strip formed by cutting the first reflecting surface 130 and the second reflecting surface 140 of the light-transmitting medium at corresponding positions. The first reflecting surface 152 of the light-transmitting single strip and the second reflecting surface 153 of the light-transmitting single strip are opposite and parallel.

[0126] Set a preset cutting pitch according to the product requirements of the final optical collimation component 10. After cutting, the light-transmitting single strip 150 has at least one cut surface 151 not covered by the molding material. For example, the light-transmitting single strips 150 at both ends have one cut surface 151, while the other light-transmitting single strips 150 have two cut surfaces 151. The cut surface 151 is also formed along the cutting route of step 104.

[0127] Step 105: Process the cut surface 151 of the light-transmitting single strip 150 to prevent stray light from entering.

[0128] There are many methods to process the cut surface 151 of the light-transmitting single strip 150. For example, roughen the cut surface 151 to make the cut surface 151 have a certain roughness, so as to prevent stray light from entering; or for example, cover a light-shielding material on the surface of the cut surface 151, that is, form a light-shielding surface, so as to achieve the purpose of preventing stray light from entering, etc. The present invention is not limited, as Figure 5 shown.

[0129] Step 106: Arrange the light-transmitting single strips 150 in a preset direction, and cut the arranged light-transmitting single strips 150 along a preset cutting line to form a plurality of reflecting elements 11 having an incident surface 111 and an exit surface 112, wherein the extending direction of the light-transmitting single strip 150 and the extending direction of the cutting line form a preset included angle, and the light beam enters from the incident surface 111 and exits from the exit surface 112, and after being reflected by the reflecting element 11 at least once, exits from the exit surface 112.

[0130] The preset included angle is related to the light beam path formed by the requirements, as Figure 22As shown. That is to say, according to the reflection to meet the optical path requirements, for example, in the projection module, it is ensured that the focal point of the optical lens is located on the surface of the projection unit, or in the receiving module, it is ensured that the optical path meets the requirements of the back focal length or the total focal length of the module, and the corresponding preset angles are different. The incident surface 111 and the exit surface 112 are two surfaces exposed when the corresponding reflection element 11 is formed by cutting. That is to say, the incident surface 111 and the exit surface 112 are formed along the cutting path of the light-transmitting single strip 150. It is worth mentioning that the distance between the preset cutting lines determines the size of the reflection element 11, especially the height size during installation and use, and those skilled in the art can design the distance between the cutting lines according to the size requirements.

[0131] In one embodiment of the present invention, as Figure 6A shown, the light-transmitting single strip 150 is placed horizontally, that is, the light-transmitting single strip 150 extends in the horizontal direction, and the preset cutting direction forms a preset angle with the extending direction of the light-transmitting single strip 150, and the light-transmitting single strip 150 is cut obliquely. In another embodiment of the present invention, as Figure 6B shown, the light-transmitting single strip 150 is placed obliquely, that is, the extending direction of the light-transmitting single strip 150 forms an angle with the horizontal direction, and the preset cutting direction extends along the horizontal direction, so as to achieve the cutting effect.

[0132] The reflection element 11 obtained by cutting by the foregoing method is as Figure 6C and Figure 6D shown. The cross-section of the reflection element 11 is a parallelogram. Since the light-transmitting single strip 150 has the light-transmitting single strip first reflection surface 152 and the light-transmitting single strip second reflection surface 153 that are opposite and parallel to each other, the reflection element 11 obtained by cutting should also have a first reflection surface 113 and a second reflection surface 114 formed by cutting at the corresponding positions, and the first reflection surface 113 and the second reflection surface 114 are opposite and parallel to each other. The incident surface 111 and the exit surface 112 of the reflection element 11 formed along the cutting line are parallel to each other. That is to say, the first reflection surface 113 and the second reflection surface 114 are inclined with respect to the incident surface 111 and the exit surface 112.

[0133] After the reflection element 11 is formed, two optical lenses 12 can be respectively installed in the preset areas of the incident surface 111 and the exit surface 112 one by one to form the optical collimation assembly 10, as Figure 7As shown. That is to say, one of the optical lenses 12 is directly attached to a preset area of the incident surface 111, and the other optical lens 12 is directly disposed in a preset area of the exit surface 112. The light beam enters the reflection element 11 from the optical lens 12 on the incident surface 111, is reflected at least twice by the mutually parallel first reflection surface 113 and the second reflection surface 114, and exits from the optical lens 12 on the exit surface 112, and the incident light beam and the exit light beam are parallel.

[0134] In another embodiment of the present invention, the optical lens 12 is disposed on the surface of the reflection element 11 by a panel process. Figure 15 It is a flowchart for assembling an optical lens and a reflection element according to an embodiment of the present invention. Specifically, after the step 105, the following steps can be executed to realize the assembly of the optical lens and the reflection element.

[0135] Step 201: Arrange the light-transmitting single strips 150 on the substrate 300 in a preset direction.

[0136] The substrate 300 can be a material suitable for later cutting, such as glass or ceramic, as Figure 9 shown.

[0137] In an embodiment of the present invention, the step 210 can simultaneously achieve the purpose of the step 105, that is, to implement the anti-stray light processing step. Specifically, the light-transmitting single strips 150 are arranged on the substrate 300 in a manner that the cutting surfaces 151 are attached to the substrate 300. The substrate 300 can be made of a light-impermeable material. Further, for the light-transmitting single strips 150 of the two cutting surfaces 151, two opposite substrates 300 can be used. That is to say, the light-transmitting single strips 150 are arranged between two opposite substrates 300 in a manner that each cutting surface 151 is attached to the corresponding substrate 300.

[0138] Step 202: Cut the light-transmitting single strips 150 and the substrate 300 along a preset cutting line to form a plurality of reflection element strips 160, wherein the extending direction of the light-transmitting single strips 150 and the extending direction of the cutting line form a preset angle, and the reflection element strip 160 includes a substrate strip 310 and a plurality of reflection elements 11 having an incident surface 111 and an exit surface 112 arranged on the substrate strip 310.

[0139] As described above, the arrangement direction of the light-transmitting single strip 150 can be horizontal or inclined, and the corresponding cutting line direction can be changed accordingly. After the light-transmitting single strip 150 is cut, a plurality of the reflection elements 11 are formed. Since the light-transmitting single strip 150 is attached to the substrate 300, the substrate 300 is also cut correspondingly, and the reflection elements 11 are correspondingly attached to the substrate strip 310 formed after the substrate 300 is cut, as Figure 10 shown. Figure 10 It is Figure 9 obtained by rotating the reflection element strip 160 obtained by cutting in

[0140] Step 203: Provide at least one optical lens mosaic 400.

[0141] As Figure 11A and Figure 11B shown, a plurality of the optical lenses 12 are arranged in an array on a transparent substrate 410 to form the optical lens mosaic 400. The arrangement of the optical lenses 12 in the light-transmitting medium 100 corresponds to the arrangement of the reflection elements 11 in the reflection element strip 160. For example, the spacing between adjacent optical lenses 12 in the same row is equal to the spacing between adjacent reflection elements 11. The optical lens mosaic 400 can be a strip shape corresponding to the size of the reflection element strip 160, or a plate shape capable of covering a plurality of reflection element strips 160.

[0142] Step 204: Arrange the reflection element strip 160 according to the spacing between adjacent rows of the optical lenses 12 of the optical lens mosaic 400, wherein the incident surface 111 or the exit surface 112 of the reflection element 11 faces outward.

[0143] For the convenience of subsequent assembly of the optical lens mosaic 400 and the reflection element strip 160, the arrangement of the reflection element strip 160 corresponds to the arrangement of the optical lenses 12 of the optical lens mosaic 400, so as to ensure that the optical lenses 12 can be installed in the preset area of the incident surface 111 or the exit surface 112 during the subsequent assembly process.

[0144] Step 205: Attach the transparent substrate 410 of the optical lens mosaic 400 to the incident surface 111 or the exit surface 112 of the reflection element 11 of the reflection element strip 160, wherein the optical lens 12 corresponds to the preset area of the incident surface 111 or / and the exit surface 112.

[0145] That is to say, the optical lens 12 is disposed on the light-transmitting substrate 410, and the light-transmitting substrate 410 is attached to the incident surface 111 or the exit surface 112 of the reflection element 11. Different from the solution where the optical lens 12 is directly attached to the incident surface 111 or the exit surface 112, this splicing process uses the light-transmitting substrate to realize the installation of the optical lens 12, which can improve the assembly efficiency, as Figure 12 shown.

[0146] Optional step 206: Remove the substrate strip 310 of the reflection element strip 160.

[0147] The step 206 is an optional step. When the substrate strip 310 is used as an anti-stray light treatment element, there is no need to remove the substrate strip 310. In embodiments where steps such as roughening have been adopted for anti-stray light treatment, the step 206 can be executed to reduce the volume.

[0148] Step 207: Divide the assembled optical lens mosaic 400 and the reflection element strip 160 to form a plurality of the optical collimation assemblies 10.

[0149] The order of the step 206 and the step 207 is not limited. Step 206 can be executed first and then step 207, that is, first remove the substrate strip 310 of the reflection element strip 160, and then only the light-transmitting substrate 410 of the optical lens mosaic 400 needs to be cut during the subsequent cutting. Or step 207 can be executed first and then step 206, that is, first perform the cutting, and during the cutting, cut the light-transmitting substrate 410 of the optical lens mosaic 400 and the substrate strip 310 of the reflection element strip 160, and then the substrate strips of each optical collimation assembly 10 can be removed one by one.

[0150] The optical collimation assemblies 10 obtained by assembling and cutting according to the above splicing process are as Figure 13 and Figure 17 shown. The cross-section of the reflection element 11 is still a parallelogram. The light-transmitting substrate 410 is cut to form a plurality of light-transmitting sub-substrates 13, and the light-transmitting sub-substrates 13 are attached to the surface of the corresponding incident surface 111 or the exit surface 112 of the reflection element 11. Specifically, one light-transmitting sub-substrate 13 is attached to the surface of the incident surface 111 of the reflection element 11, and one optical lens 12 is attached to the surface of this light-transmitting sub-substrate 13, corresponding to a preset area of the incident surface 111. Another light-transmitting sub-substrate 13 is attached to the surface of the exit surface 112 of the reflection element 11, and another optical lens 12 is attached to the surface of this another light-transmitting sub-substrate 13, corresponding to a preset area of the exit surface 112.

[0151] The light beam enters the reflection element 11 from the optical lens 12 on one side of the incident surface 111, passes through the transparent photon substrate 13 on one side of the incident surface 111, is reflected at least twice by the mutually parallel first reflection surface 113 and the second reflection surface 114, passes through the transparent photon substrate 13 on one side of the exit surface 112, and exits from the optical lens 12 of the exit surface 112, and the incident light beam and the exit light beam are parallel.

[0152] In another embodiment of the present invention, in the step 106, the single transparent strip 150 is cut twice, and the two cutting directions are perpendicular, as Figure 14A shown. For example, the single transparent strip 150 is placed horizontally, that is, the single transparent strip 150 extends in the horizontal direction. The two preset cutting directions form a preset angle with the extension direction of the single transparent strip 150, and the single transparent strip 150 is cut obliquely, and at the same time, the two preset cutting directions are perpendicular to each other.

[0153] The reflection element 11A obtained according to the foregoing method is as Figure 14B shown, and the cross section of the reflection element 11A is square. After being cut twice perpendicularly to each other, the reflection element 11A has a first reflection surface 113A, and the first reflection surface 113A extends along the diagonal of the reflection element 11A. Further, the incident surface 111A and the exit surface 112A formed along the cutting direction are perpendicular to each other, and the first reflection surface 113A faces the incident surface 111A and the exit surface 112A. The light beam enters the reflection element 11A from the incident surface 111A, is reflected once by the mutually parallel first reflection surface 113A, that is, exits from the exit surface 112A, and the incident light beam and the exit light beam are perpendicular. The reflection element 11A can be used for a periscope module.

[0154] Different cutting methods determine the final form of the reflection element 11, and those skilled in the art can design the cutting scheme according to requirements. However, it can be known that no matter how it is cut, since the surface with the reflection function adheres to an entity such as a transparent medium and no additional assembly steps are required, not only is the structural strength high, but also the process requirements are low. Taking the manufacturing scheme mentioned in the background technology as an example, in the prior art, a substrate is first provided, a reflection structure (reflection substrate) is formed by coating on the surface of the substrate, two reflection substrates are arranged face to face, and are separated by spacers in the middle to form a reflection cavity, and then the substrate is removed. When the reflection substrates are arranged face to face together, the distance D between the reflection substrates should be determined by the spacers, and it is necessary to ensure that the spacers are parallel to each other. Therefore, it is necessary to ensure that the heights of all the spacers are the same and the surfaces are flat; further, when the spacers are placed between the reflection substrates, the distances between the spacers need to be set according to the predetermined positions. Once the predetermined positions are offset, the optical element cannot be used normally.

[0155] The present invention adopts the method of coating a reflection film on a light-transmitting medium and then molding. For example, when the light-transmitting medium is implemented as glass, the grinding technology can be used to ensure that the first surface and the second surface of the glass are parallel, that is, the flatness is relatively high, thereby reducing the process difficulty. By using molding processes and roughening processes to form part of the peripheral wall of the reflection element, not only is the process mature, the process requirements are low, but also errors are not easily caused. The scheme of the prior art is prone to errors, such as the parallelism error between the substrates and the distance error between the spacers, while the present invention can ensure the flatness of the glass, and only the distance accuracy during cutting needs to be concerned.

[0156] It is worth mentioning that, in order to facilitate the improvement of the shape of the optical element, for example, the molded body formed by molding is cut so that the optical collimation assembly forms a cubic structure, as Figure 21 shown.

[0157] According to another aspect of the present invention, the present invention further provides an optical collimation assembly for a structured light projection device. The optical collimation assembly can be produced by the above-mentioned manufacturing method of the optical collimation assembly to achieve the purpose and advantages of the present invention.

[0158] As Figure 16As shown, the optical collimation assembly 10 includes the reflection element 11 and at least one optical lens 12. The reflection element 11 includes a reflection body 115 and a molded body 116. The reflection body 115 is made of a solid light-transmitting medium. The reflection body 115 has two reflection surfaces, namely the first reflection surface 113 and the second reflection surface 114, and the first reflection surface 113 and the second reflection surface 114 are opposite and parallel to each other. The first reflection surface 113 and the second reflection surface 114 can be formed by covering a reflection material on the surface of the light-transmitting medium. The reflection body 115 further has an incident surface 111 and an exit surface 112, and the incident surface 111 and the exit surface 112 are opposite to each other. Preferably, the incident surface 111 and the exit surface 112 are opposite and parallel to each other. The molded body 116 covers the first reflection surface 113 and the second reflection surface 114, and the molded body 116 surrounds the circumferential sides of the incident surface 111 and the exit surface 112.

[0159] Furthermore, the reflection body 115 is in a hexahedral three-dimensional structure, where two surfaces are the first reflection surface 113 and the second reflection surface 114, two surfaces are the incident surface 111 and the exit surface 112, and the remaining two surfaces are stray light prevention surfaces, which can be achieved by means such as surface roughening treatment, coating a light-shielding material, or attaching a light-shielding plate.

[0160] In an embodiment of the present invention, the optical lens 12 is attached to a preset area of the incident surface 111 or the exit surface 112. Preferably, one optical lens 12 is directly attached to the preset area of the incident surface 111, and the other optical lens 12 is directly disposed in the preset area of the exit surface 112. The light beam enters the reflection element 11 from the optical lens 12 on the incident surface 111, is reflected at least twice by the mutually parallel first reflection surface 113 and the second reflection surface 114, and exits from the optical lens 12 on the exit surface 112, and the incident light beam and the exit light beam are parallel.

[0161] Or, in another embodiment of the present invention, as Figure 17As shown, the optical collimation assembly 10 further includes at least one light-transmitting substrate 13. The light-transmitting substrate 13 is made of a light-transmitting material. The light-transmitting substrate 13 is attached to the surface of the incident surface 111 or the exit surface 112. The optical lens 12 is attached to the surface of the light-transmitting substrate 13, corresponding to a preset area of the incident surface 111 or the exit surface 112. Preferably, one light-transmitting substrate 13 is attached to the surface of the incident surface 111 of the reflecting element 11, and one optical lens 12 is attached to the surface of this light-transmitting substrate 13, corresponding to the preset area of the incident surface 111. Another light-transmitting substrate 13 is attached to the surface of the exit surface 112 of the reflecting element 11, and another optical lens 12 is attached to the surface of this other light-transmitting substrate 13, corresponding to the preset area of the exit surface 112.

[0162] The light beam enters the reflecting element 11 from the optical lens 12 on the side of the incident surface 111, passes through the light-transmitting substrate 13 on the side of the incident surface 111, is reflected at least twice by the mutually parallel first reflecting surface 113 and the second reflecting surface 114, passes through the light-transmitting substrate 13 on the side of the exit surface 112, and exits from the optical lens 12 on the exit surface 112, and the incident light beam and the exit light beam are parallel.

[0163] In another embodiment of the present invention, as Figure 18A shown, the optical collimation assembly 10B includes a reflecting element 11B. The reflecting element 11B includes the reflecting body 115B and the molding body 116B. The reflecting body 115B has two reflecting surfaces, namely the first reflecting surface 113B and the second reflecting surface 114B, the incident surface 111B and the exit surface 112B. Different from the foregoing embodiment, the first reflecting surface 113B and the second reflecting surface 114B are respectively implemented as a free-form surface. The reflecting element 11B directly collimates the light beam through the free-form surface. Therefore, the optical lens can be cancelled in this embodiment. It is worth mentioning that since the first reflecting surface 113B and the second reflecting surface 114B are designed as the free-form surface, during the manufacturing process of the reflecting element, the light-transmitting medium 100 directly forms the corresponding free-form surface. For example, when the light-transmitting medium 100 is implemented as glass, the light-transmitting medium 100 can be directly molded to form a module with the free-form surface, and then the reflecting surface is coated with a film.

[0164] Preferably, the reflection element 11B has a turning angle α of 50° to 75°. Taking the turning angle α of 60° as an example, when the light beam enters the reflection body 115B and is reflected by the first reflection surface 113B or the second reflection surface 114B, the incident angle and the reflection angle are preferably also 60°, so that the light beam can be better collimated. In other words, preferably, the incident angle and the reflection angle when the light beam is reflected are equal to the turning angle of the reflection element 11B.

[0165] Optionally, the turning angle of the light beam on the free-form surface is 60° to 150°. Preferably, the turning angle of the light beam on the free-form surface is 90° to 120°. When the turning angles of the light beam on the first reflection surface 113B and the second reflection surface 114B are equal, it can be ensured that the light beam enters vertically from the incident surface 111B and exits vertically from the exit surface 112B, so that the outgoing light ray and the incident light ray passing through the optical collimation assembly 10B are kept parallel.

[0166] Compared with the flat reflection surface design, the free-form surface coating is easier. Secondly, the free-form surface design is insensitive to horizontal displacement and reduces the assembly difficulty. In the embodiment of the present invention, for the entire structured light projection device, since the optical lens is cancelled, the light tilt can be more easily controlled. The less the light beam passes through the device, the lower the brightness becomes, and the higher the efficiency is. The power of the projection unit can be reduced to a certain extent; furthermore, the uniformity of the brightness can be ensured. Of course, the optical collimation assembly 10B may further include at least one optical lens 12B for further collimation. The optical lens 12B is disposed in a preset area of the incident surface 111B or the exit surface 112B, so as to collimate the light beam through the free-form surface and the optical lens, making the collimation effect of the light beam better, as Figure 18B shown.

[0167] The reflection element obtained by different cutting methods will be different. Figure 19 This is a structural diagram of another optical collimation assembly of the present invention. The optical collimation assembly 10A includes the reflection element 11A and at least one optical lens 12A. The reflection element 11A includes a reflection body 115A and a molded body 116A.

[0168] Different from the previous embodiments, the reflection body 115A has the first reflection surface 113A. That is to say, the reflection body 115A has only one reflection surface. The first reflection surface 113A is formed by covering a reflection material on the surface of the light-transmitting medium and then cutting. The reflection body 115A further has the incident surface 111A and the exit surface 112A, and the incident surface 111A and the exit surface 112A are perpendicular to each other. The first reflection surface 113A faces the incident surface 111A and the exit surface 112A. The molded body 116A covers the first reflection surface 113A.

[0169] That is to say, the cross section of the reflection element 11A is square. The first reflection surface 113A extends along the diagonal of the reflection element 11A. The light beam enters the reflection element 11A from the incident surface 111A, is reflected once by the first reflection surface 113A, and then exits from the exit surface 112A, and the incident light beam and the exit light beam are perpendicular. The reflection element 11A can be used in an edge-emitting structured light module, and the reflection element 11A collimates the light emitted by the edge-emitting laser and turns the optical path.

[0170] It is worth mentioning that in some special projection structures, the incident light ray and the exit light ray are required not to be parallel. Correspondingly, the first reflection surface 113 and the second reflection surface 114 are not parallel either, as Figure 20 shown. The relative inclination of the first reflection surface 113 and the second reflection surface 114 is set according to the preset route of the light beam. The non-parallel first reflection surface 113 and second reflection surface 114 only need to correspondingly set the first surface and the second surface of the light-transmitting medium 100, which can be realized by processes such as polishing and molding, and will not be elaborated here.

[0171] Furthermore, the reflection body 115 is a six-sided three-dimensional structure, where two sides are the first reflection surface 113 and the second reflection surface 114, two sides are the incident surface 111 and the exit surface 112, and the remaining two sides are anti-stray light surfaces, which can be realized by roughing the surface, coating a light-shielding material or attaching a light-shielding plate, etc.

[0172] According to another aspect of the present invention, the optical collimation assembly of the present invention can be applied to a structured light projection device to achieve the objectives and advantages of the present invention, as Figures 23 to 28 shown.

[0173] Specifically, the structured light projection device includes the optical collimation assembly 10, an optical diffraction element 20, and a projection unit 30. The optical collimation assembly 10 is disposed between the projection unit 30 and the optical diffraction element 20. The beam emitted by the projection unit 30 is collimated by the optical collimation assembly 10, and then diffracted or replicated by the optical diffraction element 20 and projected onto the surface of the spatial target. The projection unit 30 can be implemented as a VCSEL (Vertical Cavity Surface Emitting Laser). When the projection unit 30 is implemented as a VCSEL, the projection unit 30 can project multiple beams. The optical collimation assembly 10 can adopt any of the above structures. The first reflection surface and the second reflection surface can be flat or free-form surfaces. An optical lens can be directly attached to the incident surface and the reflection surface, or a photon-transmitting substrate structure can be used, etc. There is no limitation here. The optical diffraction element 20 can adopt a single-layer structure (such as Figure 23 as shown), or a double-layer structure (such as Figure 24 as shown). The present invention is not limited.

[0174] In one embodiment, in order to improve the collimation effect of the structured light projection device, as Figure 25 shown, the optical diffraction element 20 includes a collimation portion 21 and a diffraction portion 22. The beam collimated by the optical collimation assembly 10 is further collimated by the collimation portion 21 and then reaches the spatial target through the diffraction portion 22. The diffraction portion 22 is disposed on the beam emission side of the collimation portion 21 to diffract and expand the beam that has been collimated again. Preferably, the optical diffraction element 20 is implemented as a metalens. Preferably, the collimation portion is set as a convex lens or a Fresnel lens, so that collimation can be performed. It is worth mentioning that in this embodiment, the positional relationship between the collimation portion 21 and the diffraction portion 22 is not limited. It can also be diffracted first and then collimated, that is, the collimation portion 21 is disposed on the beam emission side of the diffraction portion 22.

[0175] In one embodiment of the present invention, as Figures 26 to 28As shown, the structured light projection device further includes a circuit board 40 and a detection circuit 50. The projection unit 30 is disposed on the circuit board 40 and electrically connected to the circuit board 40. After the light beam projected by the projection unit 30 is received and collimated by the optical collimation assembly 10, it is diffracted and beam-expanded by the optical diffraction element 20 and then projected onto a spatial target. Since the projection unit 30 is implemented as a VCSEL, the projection energy is relatively large. Especially, the zero-order problem can cause harm to the human eye. Therefore, it is necessary to avoid the occurrence of zero-order diffraction or the direct arrival of the light beam at the human eye without diffraction. Therefore, it is necessary to ensure the integrity of the structure of the optical diffraction element 30. Thus, the detection circuit 50 is disposed on the surface of the optical diffraction element 20 to detect whether the optical diffraction element 20 is intact.

[0176] The detection circuit 50 is preferably implemented as ITO (indium tin oxide) coated on the surface of the optical diffraction element 20. The detection circuit 50 is electrically connected to the circuit board 40 to detect the optical diffraction element 20. For example, the ITO is coated on the surface of the optical diffraction element 20 to form a capacitive structure. When the surface of the optical diffraction element 20 is damaged or has water vapor or water droplets, the capacitance value of the capacitive structure changes, so that the corresponding processor determines that the optical diffraction element 20 is abnormal and interrupts the operation of the structured light projection device to ensure the safety of the human eye. The detection circuit 50 can also be composed of other materials (preferably transparent materials) and detect by means of resistance, inductance, etc.

[0177] It is worth mentioning that the detection circuit 50 needs to be electrically connected to the circuit board 40. Therefore, in this embodiment of the present invention, an electrically conductive circuit 60 is further formed on the surface of the optical reflection element 10 by means of LDS (Laser Direct Structuring) technology. The electrically conductive circuit 60 electrically connects the detection circuit 50 to the circuit board 40. It is worth noting that in the prior art, when the side wall of the reflection element is made of glass or other substrates, it is impossible to form a circuit by LDS. Generally, an external circuit structure is added, which increases the size of the entire projection module. However, in the present invention, since the side wall of the reflection element is formed by a molding process and the LDS process can be implemented on the molding material, the present invention can dispose the electrically conductive circuit 60 on the surface of the molded body 116 by means of the LDS process, so that no additional circuit needs to be provided, reducing the process difficulty and the overall volume of the projection module.

[0178] Alternatively, the electrically conductive circuit 60 is implemented as a conductive member. During the manufacturing process, a plurality of conductive members are provided in advance. After the molding and injection molding are completed, the conductive members are wrapped in the molding layer 200. The detection circuit 50 is connected to the circuit board 40 through the conductive members.

[0179] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments, and without departing from the said principles, any variations or modifications can be made to the embodiments of the present invention.

Claims

1. A reflective element, characterized in that, Comprising: A reflection body and a molded body, wherein the reflection body is made of a solid light-transmitting medium, the reflection body has two reflection surfaces, an incident surface and an exit surface, wherein the molded body is molded outside the reflection surfaces, wherein the two reflection surfaces are opposite and parallel, and are inclined with respect to the incident surface and the exit surface, so that a light beam enters the reflection element from the incident surface, is reflected at least twice by the reflection surfaces, and exits from the exit surface, so that the incident light beam and the exit light beam are parallel, wherein the two reflection surfaces are implemented as free-form surfaces, and the turning angle of the free-form surface is 50° to 75°.

2. The reflective element according to claim 1, wherein the reflective surface is formed by covering a reflective material on the surface of a light-transmitting medium.

3. The reflective element according to claim 1, wherein the incident surface and the exit surface are opposite and parallel, and the cross-section of the reflective element is a parallelogram.

4. The reflective element according to claim 1, wherein the two reflective surfaces are implemented as flat surfaces.

5. The reflective element according to claim 1, wherein the turning angle of the light beam on the free-form surface is 60° to 150°.

6. The reflective element according to claim 1, wherein the turning angle of the light beam on the free-form surface is 90° to 120°.

7. The reflective element according to any one of claims 1 to 6, wherein the reflective body further has at least one anti-stray light surface, and the anti-stray light surface is formed by any one of the methods of roughening the surface of the reflective body, coating a light-shielding material, or attaching a light-shielding plate.

8. An optical collimation assembly for a structured light projection device, characterized in that, Comprising: The reflection element according to any one of claims 1 to 7; And At least one optical lens, wherein the optical lens is installed in a preset area of the incident surface or / and the exit surface to achieve collimation.

9. The optical collimation assembly according to claim 8, further comprising at least one transparent substrate, wherein the transparent substrate is made of a light-transmitting material, the transparent substrate is attached to the surface of the incident surface or / and the exit surface, and the optical lens is attached to the surface of the transparent substrate corresponding to a preset area of the incident surface or / and the exit surface.

10. A structured light projection device, characterized in that, Comprising: A projection unit for emitting a light beam; The optical collimation assembly according to claim 8 or 9, wherein the optical collimation assembly collimates the light beam emitted by the projection unit; And An optical diffraction element, wherein the light beam emitted by the projection unit is collimated by the optical collimation assembly, and then diffracted or replicated by the optical diffraction element and projected onto the surface of a spatial target.

11. The structured light projection device according to claim 10, wherein the optical diffraction element includes a collimation part and a diffraction part, and the diffraction part is disposed on the light beam emission side of the collimation part, so that the light beam collimated by the optical collimation assembly is further collimated by the collimation part and then reaches a spatial target through the diffraction part.

12. The structured light projection device according to claim 11 further includes a circuit board and a detection circuit, wherein the projection unit is disposed on the circuit board and electrically connected to the circuit board, and the detection circuit is disposed on the surface of the optical diffraction element and electrically connected to the circuit board for detecting whether the optical diffraction element is intact.

13. The structured light projection device according to claim 12, wherein the detection circuit is implemented as ITO and is plated on the surface of the optical diffraction element.

14. The structured light projection device according to claim 12 further includes a conduction circuit, wherein the conduction circuit electrically connects the detection circuit and the circuit board, and the conduction circuit is formed on the surface of the molded body by adopting an LDS process.

15. The structured light projection device according to claim 12 further includes a conduction circuit, wherein the conduction circuit electrically connects the detection circuit and the circuit board, and the conduction circuit is wrapped by the molded body.

16. A method for manufacturing an optical collimation assembly for a structured light projection device, characterized in that Comprising: Step (a): Form a first light-transmitting medium reflection surface and a second light-transmitting medium reflection surface on opposite and parallel first and second surfaces of a solid light-transmitting medium; Step (b): Form a molded layer wrapping the light-transmitting medium having the first light-transmitting medium reflection surface and the second light-transmitting medium reflection surface, wherein the molded layer is made of an opaque material; Step (c): Cut the light-transmitting medium with the molded layer at a preset interval to form a plurality of light-transmitting single strips; And Step (d): Arrange the light-transmitting single strips in a preset direction, and cut the arranged light-transmitting single strips along a preset cutting line to form a plurality of reflection elements having an incident surface and an exit surface, wherein the extending direction of the light-transmitting single strip and the extending direction of the cutting line form a preset included angle, so that a light beam enters the reflection element from the incident surface, is reflected by the reflection element at least once, and exits from the exit surface, wherein the first light-transmitting medium reflection surface and the second light-transmitting medium reflection surface are opposite and parallel free-form surfaces, and the turning angle of the free-form surfaces of the first light-transmitting medium reflection surface and the second light-transmitting medium reflection surface is 50° to 75°.

17. The method for manufacturing an optical collimation assembly according to claim 16, wherein in step (a), the first reflective surface of the light-transmitting medium and the second reflective surface of the light-transmitting medium are formed by covering the first surface and the second surface with a material having a light-reflecting property.

18. The method for manufacturing an optical collimation assembly according to claim 16 further includes, before step (d): Step (e): Process the cut surface of the light-transmitting single strip to form an anti-stray light surface to prevent stray light from entering.

19. The method for manufacturing an optical collimation assembly according to claim 18, wherein in step (e), the anti-stray light surface is formed by roughening the cut surface.

20. The method for manufacturing an optical collimation assembly according to claim 18, wherein in step (e), the anti-stray light surface is formed by covering the surface of the cut surface with a light-shielding material.

21. The method for manufacturing an optical collimation assembly according to claim 18, wherein in step (d), the light-transmitting single strip extends in the horizontal direction, and a preset cutting direction forms a preset angle with the extending direction of the light-transmitting single strip, and the light-transmitting single strip is cut obliquely.

22. The method for manufacturing an optical collimation component according to claim 18, wherein in the step (d), the light-transmitting single strip is placed obliquely, and the preset cutting direction extends in the horizontal direction.

23. The method for manufacturing an optical collimation component according to claim 16, wherein the step (d) further comprises the steps of: Step (d.1) arranging the light-transmitting single strip on the substrate in a preset direction; and Step (d.2) cutting the light-transmitting single strip and the substrate along a preset cutting line to form a plurality of reflection element strips, wherein the extending direction of the light-transmitting single strip and the extending direction of the cutting line form a preset included angle, and the reflection element strip comprises a substrate strip and a plurality of the reflection elements having the incident surface and the exit surface arranged on the substrate strip.

24. The method for manufacturing an optical collimation component according to claim 16, further comprising: Step (e): Install an optical lens one by one in a preset area of the incident surface or the exit surface.

25. The method for manufacturing an optical collimation component according to claim 23, further comprising: Step (f): Arrange the reflection element strips according to the spacing between adjacent rows of optical lenses in an optical lens mosaic, wherein the arrangement of the optical lenses in the optical lens mosaic corresponds to the arrangement of the reflection elements in the reflection element strips; Step (g): Attach the light-transmitting substrate of the optical lens mosaic to the incident surface or the exit surface of the reflection elements in the reflection element strips, wherein the optical lens corresponds to a preset area of the incident surface or the exit surface.

26. The method for manufacturing an optical collimation component according to claim 25, further comprising: Step (h): Remove the substrate strips of the reflection element strips.

27. The method for manufacturing an optical collimation component according to claim 25 or 26, further comprising: Step (i): Split the assembled optical lens mosaic and the reflection element strip to form a plurality of the optical collimation assemblies.

28. The method for manufacturing an optical collimation component according to claim 16, wherein the light-transmitting single strip in the step (d) is cut twice, and the two preset cutting directions are perpendicular, so that the incident surface and the exit surface of the formed reflection element are perpendicular, and the light beam enters the reflection element from the incident surface, and after being reflected by the reflection element once, exits from the exit surface.

29. The method for manufacturing an optical collimation component according to claim 16, wherein the exit surface formed after cutting in the step (d) is a corresponding pair of opposite and parallel free-form surfaces.

30. The method for manufacturing an optical collimation component according to claim 28, wherein the turning angle of the free-form surface of the exit surface is 50° to 75°.

31. The method for manufacturing an optical collimation component according to claim 23, wherein in the step (d.1), the light-transmitting single strip is arranged on the substrate in such a way that its cutting surface is attached to the substrate.

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