CN111812853A

CN111812853A - Reflective element, optical collimating assembly, method of manufacturing the same, and structured light projection device

Info

Publication number: CN111812853A
Application number: CN201910288951.6A
Authority: CN
Inventors: 黄桢; 栾仲禹; 许晨祥; 干洪锋; 刘丽; 陈振宇
Original assignee: Ningbo Sunny Opotech Co Ltd
Current assignee: Ningbo Sunny Opotech Co Ltd
Priority date: 2019-04-11
Filing date: 2019-04-11
Publication date: 2020-10-23

Abstract

The invention provides a reflecting element, an optical collimation assembly, a manufacturing method thereof and a structured light projection device, wherein the reflecting element comprises a reflecting main body and a molded body, wherein the reflecting main body is made of a solid light-transmitting medium, the reflecting element is provided with at least one reflecting surface, an incident surface and an emergent surface, and the molded body is molded and formed outside the reflecting surface so that light beams enter the reflecting element from the incident surface and are emitted from the emergent surface after being reflected by the reflecting surface at least once.

Description

Reflective element, optical collimating assembly, method of manufacturing the same, and structured light projection device

Technical Field

The present invention relates to a structured light projection device, and more particularly, to a reflective device, an optical collimating assembly, a method of manufacturing the same, and a structured light projection device, which can reduce the process requirements and increase the yield.

Background

There are many technical schemes for realizing depth camera shooting, and the mainstream schemes include a binocular scheme, a TOF scheme and a structured light scheme. The binocular scheme is low in cost, but the biggest problem is that the algorithm needs high computing resources, so that the real-time performance is poor, the basic tracking resolution is high, and the detection precision is hooked. That is, the higher the resolution and the higher the required accuracy, the more complex the calculation, while the pure binocular solution is affected by the illumination and the texture properties of the object.

The structured light scheme 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 an object, and adopts a method of actively projecting a known pattern to realize fast and robust matching of feature points, so that higher precision can be achieved, and the application range is greatly expanded. With the gradual development and improvement of the structured light technology, the structured light depth camera is also increasingly popular in the market, and especially the application of the structured light depth camera in a mobile terminal attracts the attention of many mobile manufacturers, for example, the Iphone X front camera module adopts the speckle structured light technology to perform face recognition unlocking.

The structured light depth camera basically works in the process that structured light is projected to the surface of an object to be measured and then is modulated by the height of the object to be measured, the modulated structured light is collected by a camera system and is transmitted to a computer for analysis and calculation, and then three-dimensional surface shape data of the object to be measured can be obtained. The projection device used by the existing structured light depth camera comprises a light emitter, a collimating mirror and an optical diffraction element, wherein the collimating mirror is arranged between the light emitter and the optical diffraction element. The light emitted by the light emitter is collimated by the collimating mirror, diffracted or copied by the optical diffraction element and then projected to the surface of the space target.

However, as the terminal becomes thinner, the demand for the camera is gradually developing toward miniaturization, wherein how to reduce the height dimension of the camera becomes an inevitable problem. The reduction in height is a problem because of the back or focal length that must be ensured during the design or operation of the module. In order to solve this problem, many modules are reduced in size while the optical path is kept constant by adding an optical reflection element.

For example, in a patent publication US20170075205A1 entitled "Integrated light pipe for optical projection" (Integrated light pipe for optical projection), an integrated light pipe is disclosed in which a reflective space is formed by two light-transmissive substrates that are relatively parallel and two reflective plates that are relatively parallel. The two reflecting plates are oppositely provided with mutually parallel reflecting surfaces capable of reflecting light rays, and each reflecting surface is inclined relative to the light-transmitting substrate. And opposite optical lenses are respectively arranged on two sides of the preset area of each light-transmitting substrate. The light enters from the two optical lenses at the incident side, is reflected by the opposite and parallel reflecting surfaces, and then is emitted from the two optical lenses at the emergent side, so that the aim of collimation is fulfilled.

In the scheme, the two reflecting plates need to be parallel to ensure that the opposite reflecting surfaces of the two reflecting plates are parallel, so that the light after being reflected is parallel to the light before being reflected, and the light cannot be scattered in the reflecting process. However, it is highly process-demanding to ensure that the two reflective plates and the two reflective surfaces are parallel, and sensitive light rays are diverted once the reflective surfaces are not parallel. In this publication US20170075205a 1a solution is disclosed in which two reflecting plates are spaced apart by a spacer element. However, even if the two surfaces of the spacer member, which are in contact with the two reflection plates, respectively, are parallel to each other, the two reflection plates are easily misaligned during the assembly process with the spacer member, resulting in the non-parallelism of the two reflection plates. For example, the fixing glue between the spacer element and the reflector plate is not uniform, or the surface of the reflector plate in contact with the spacer element is not flat itself, etc. That is, the requirement of this solution on the manufacturing process is very high, which easily causes the product to be out of order, the product yield is low, and it is not suitable for mass production. This production solution is not suitable, in particular, for devices with high requirements for optical precision.

In addition, because the center of the integrated light pipe is a cavity, the whole can only be kept stable and parallel between the reflecting plates by virtue of the connection between the two light-transmitting substrates and the two reflecting plates. Once the light-transmitting substrate is impacted or impacted, the connection between the light-transmitting substrate and the reflecting plate is easily damaged, so that the whole light-transmitting substrate is easily scattered, the reflecting plate is easily moved to generate errors, and the whole light-transmitting substrate can be scattered.

Disclosure of Invention

An object of the present invention is to provide a reflective element, an optical collimating assembly, a method for manufacturing the same, and a structured light projection apparatus, wherein the optical collimating assembly has a small reduction size, especially a small height size, while the optical path length of the reflective element is not changed, and is suitable for the current miniaturization development.

It is another object of the present invention to provide a reflective element, an optical collimating assembly, a method of manufacturing the same, and a structured light projection device, wherein the optical collimating assembly is of a solid structure, has high structural strength, and is not prone to scattering under impact forces.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method of manufacturing the same, and a structured light projection apparatus, wherein the optical collimating assembly has a high structural strength, and particularly, the possibility that two reflecting surfaces, which are opposite and parallel, will not move or deform due to an impact is reduced, thereby ensuring accuracy.

It is a further object of the invention to provide a reflective element, an optical collimating assembly, a method of manufacturing the same and a structured light projection device, wherein the optical collimating assembly is compact and suitable for use in devices with high requirements for optical precision.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method of manufacturing the same, and a structured light projection device, wherein the method of manufacturing the optical collimating assembly has low requirements for manufacturing processes and high yield.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method of manufacturing the same, and a structured light projection device, wherein the method of manufacturing the optical collimating assembly uses a first surface and a second surface of a light transmissive medium to form reflective surfaces, and the first surface and the second surface can be made parallel by well-established existing processes such as polishing, with low requirements for manufacturing processes.

Another object of the present invention is to provide a reflective device, an optical collimating assembly, a method of manufacturing the same, and a structured light projection apparatus, wherein the method of manufacturing the optical collimating assembly uses a first surface and a second surface of a light transmissive medium to form reflective surfaces, and the first surface and the second surface can be parallel by a mature existing process such as polishing, thereby ensuring precision, and improving product yield.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method for manufacturing the same, and a structured light projection device, in which optical lenses can be directly mounted on predetermined regions of the incident surface and the exit surface of the optical collimating assembly, or mounted by using a plate splicing process, so as to achieve the purpose of collimation. That is, a person skilled in the art can select an appropriate mounting process according to actual conditions, thereby facilitating production.

It is a further object of the invention to provide a reflective element, an optical collimating assembly, a method of manufacturing the same and a structured light projection device, wherein the reflective surface of the optical collimating assembly is implemented as a free-form surface through which the light beam is directly collimated.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method for manufacturing the same, and a structured light projection apparatus, wherein an optical diffraction element of the structured light projection apparatus has a collimating function, and a light beam collimated by the optical collimating assembly can be further collimated by the optical diffraction element, so as to improve a collimating effect.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method for manufacturing the same, and a structured light projection apparatus, wherein an optical diffraction element of the structured light projection apparatus has a collimating function, and requirements for an optical lens surface shape and curvature of the optical collimating assembly can be reduced, thereby reducing processing difficulty.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method for manufacturing the same, and a structured light projection apparatus, wherein a detection circuit is disposed on a surface of an optical diffraction element, so as to detect the conduction of the detection circuit, thereby ensuring the structural integrity of the optical diffraction element, and preventing the damage of the optical diffraction element to human eyes due to the projection capability.

Another object of the present invention is to provide a reflective element, an optical collimating assembly, a method for manufacturing the same, and a structured light projection apparatus, wherein the reflective element is molded to form a sidewall, so as to facilitate the connection between the detection circuit and the circuit board through an LDS (Laser direct structuring) process, without requiring an external circuit structure, thereby reducing the process difficulty and the overall volume of the projection module.

In order to achieve at least one of the above objects of the present invention, according to one aspect of the present invention, there is further provided a reflective element comprising:

the reflecting element comprises a reflecting body and a molded body, wherein the reflecting body is made of a solid light-transmitting medium and is provided with at least one reflecting surface, an incident surface and an emergent surface, and the molded body is molded and formed outside the reflecting surface so that light beams enter the reflecting element from the incident surface and are emitted from the emergent surface after being reflected at least once by the reflecting surface.

According to one embodiment of the present invention, the reflective surface is formed by covering a surface of the light transmitting medium with a reflective material.

According to one embodiment of the present invention, the reflective element has two reflective surfaces, wherein the two reflective surfaces are opposite and parallel, and are inclined with respect to the incident surface and the exit surface, so that the light beam enters the reflective element from the incident surface, is reflected at least twice by the reflective surfaces, and exits from the exit surface, and thus the incident light beam and the exit light beam are parallel.

According to one embodiment of the invention, the entrance face and the exit face are opposite and parallel, and the cross section of the reflecting element is a parallelogram.

According to one embodiment of the invention, both said reflecting surfaces are implemented as flat surfaces.

According to one embodiment of the invention, both said reflecting surfaces are implemented as free-form surfaces.

According to one embodiment of the invention, the turning angle of the free-form surface is 50 ° to 75 °.

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

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

In another aspect, the present invention further provides an optical collimating assembly for a structured light projection device, comprising:

any of the reflective elements described above; and

and the optical lens is arranged on the incident surface or/and the emergent preset area to realize collimation.

According to an embodiment of the present invention, the optical collimating assembly further includes at least one light transmissive sub-substrate, wherein the light transmissive sub-substrate is made of a light transmissive material, wherein the light transmissive sub-substrate is attached to the surface of the incident surface or \ and the exit surface, and wherein the optical lens is attached to the surface of the light transmissive sub-substrate corresponding to the predetermined area of the incident surface or \ and the exit surface.

In another aspect of the present invention, there is further provided a structured light projection device, comprising:

a projection unit for emitting a light beam;

any one of the optical collimating assemblies described above, wherein the optical collimating assembly collimates the light beam emitted by the projection unit; and

and the light beam emitted by the projection unit is collimated by the optical collimating component, is diffracted or copied by the optical diffraction element and is projected to a space target surface.

According to an embodiment of the present invention, the optical diffraction element includes a collimating part and a diffracting part, wherein the diffracting part is disposed on a beam emitting side of the collimating part, so that the beam collimated by the optical collimating component is further collimated by the collimating part and then reaches the spatial target through the diffracting part.

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

According to one embodiment of the invention, the detection circuit is implemented as ITO, plated on the surface of the optical diffraction element.

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

According to an embodiment of the present invention, the structured light projection device further includes a conduction circuit, wherein the conduction circuit conducts the detection circuit and the wiring board, wherein the conduction circuit is encapsulated by the molded body.

In another aspect, the present invention further provides a method of manufacturing an optical collimating assembly for a structured light projection device, comprising:

(a) forming a transparent medium on the opposite and parallel first and second surfaces of a solid transparent medium

A reflecting surface and a second reflecting surface of a light-transmitting medium;

(b) the package is formed with the first reflecting surface of the light-transmitting medium and the second reflecting surface of the light-transmitting medium

The molding layer of the light-transmitting medium, wherein the molding layer is made of an opaque material;

(c) cutting the light-transmitting medium with the molding layer according to a preset interval to form a plurality of light-transmitting single strips; and

(d) arranging the light-transmitting single strips in a preset direction, cutting the light-transmitting single strips in the preset cutting line arrangement to form a plurality of reflecting elements with incident surfaces and emergent surfaces, wherein the extending direction of the light-transmitting single strips and the extending direction of the cutting line form a preset included angle, so that light beams enter the reflecting elements from the incident surfaces, and the light beams are reflected by the reflecting elements at least once and then are emitted from the emergent surfaces.

According to one embodiment of the present invention, the step (a) forms the first and second reflective surfaces by covering the first and second surfaces with a material having light reflecting properties.

According to an embodiment of the present invention, before the step (d), the optical collimating assembly manufacturing method further comprises:

(e) and processing the cutting surface of the light-transmitting single strip to form a stray light preventing surface so as to prevent stray light from entering.

According to an embodiment of the present invention, the step (e) forms the light-mixing prevention surface by roughening the cut surface.

According to an embodiment of the present invention, the step (e) forms the light-shading prevention surface by covering a surface of the cut surface with a light-shielding material.

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

According to an embodiment of the present invention, the single transparent strip in step (d) is placed obliquely, and the predetermined cutting direction extends along a horizontal direction.

According to an embodiment of the present invention, the step (d) further comprises the steps of:

(d.1) arranging the single light-transmitting strips on the substrate in a preset direction; and

(d.2) forming a plurality of reflecting element strips by the light-transmitting single strips and the substrate which are cut according to preset cutting lines, wherein the extending direction of the light-transmitting single strips and the extending direction of the cutting lines form a preset included angle, and the reflecting element strips comprise substrate strips and a plurality of reflecting elements which are arranged on the substrate strips and provided with the incident surfaces and the emergent surfaces.

According to an embodiment of the present invention, the method for manufacturing an optical collimating assembly further comprises:

(e) and mounting the optical lenses in the preset area of the incident surface or the emergent surface one by one.

According to an embodiment of the invention, the optical collimating assembly manufacturing method further comprises:

(f) arranging the reflecting element strips according to the space between adjacent rows of optical lenses of an optical lens makeup, wherein the arrangement of the optical lenses in the optical lens makeup corresponds to the arrangement of the reflecting elements in the reflecting element strips;

(g) and attaching the transparent substrate of the optical lens makeup to the incident surface or the emergent surface of the reflecting element strip, wherein the optical lens corresponds to a preset area of the incident surface or the emergent surface.

(h) removing the base strip of the strips of reflective elements.

(i) splitting the assembled optical lens imposition and the reflective element strip to form a plurality of the optical collimating assemblies.

According to an embodiment of the present invention, in the step (d), the single transparent 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, is reflected once by the reflective element, and then exits from the exit surface.

According to an embodiment of the present invention, in the step (a), the first surface and the second surface 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 a turning angle of the free-form surfaces of the incident surface and the exit surface is 50 ° to 75 °.

According to an embodiment of the present invention, the transparent single strips in step (d.1) are arranged on the substrate in a manner that the cutting surfaces of the transparent single strips are attached to the substrate.

Drawings

FIG. 1 is a perspective view of a light-transmissive medium of a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 2A is a diagram of a transparent medium, a process for forming a first reflective surface of the transparent medium and a second reflective surface of the transparent medium according to a method for fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 2B is a diagram of another process for forming a first reflective surface and a second reflective surface of an optically transmissive medium for a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 2C is a perspective view of a light-transmitting medium after forming a first reflective surface and a second reflective surface of the light-transmitting medium according to a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 2D is a cross-sectional view of an alternative optically transmissive medium after formation of a first reflective surface and a second reflective surface of the optically transmissive medium for a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 3A is a cross-sectional view of a light-transmitting medium after molding for a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 3B is a perspective view of a light-transmitting medium after molding for a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 4 is a cut-out schematic view of a light-transmitting medium after molding for a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 5 is a schematic view of a cut surface of a transparent single strip after anti-veiling treatment according to a method of manufacturing an optical collimating assembly according to an embodiment of the present invention.

Fig. 6A and 6B are schematic diagrams of a light-transmissive single-strip arrangement and cutting pattern of a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 6C is a perspective view of a reflective element resulting from a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 6D is a cross-sectional view of the reflective element resulting from a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 7 is a light transmissive element mounting arrangement of a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 8 is a flow chart of a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 9 is a schematic diagram of a light-transmissive single strip alignment and cut pattern for a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

Fig. 10 is a rotated cross-sectional view of the resulting strip of reflective elements cut according to the method of fig. 9.

FIG. 11A is a top plan view of an optical lens imposition of a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 11B is a side view of an optical lens imposition of a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 12 is an optical lens imposition and light transmitting single bar assembly drawing of a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

Fig. 13 is a cross-sectional view of the assembled and cut reflective element according to fig. 12.

FIG. 14A is a schematic diagram of another light-transmissive single strip alignment and cut pattern for a method of fabricating an optical collimating assembly according to one embodiment of the present invention.

FIG. 14B is a perspective view of another reflective element resulting from a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 15 is a flow chart of another installation of a light-transmissive element of a method of manufacturing an optical collimating assembly according to one embodiment of the present invention.

FIG. 16 is a cross-sectional view of an optical collimating assembly according to one embodiment of the present invention.

FIG. 17 is a cross-sectional view of an optical collimating assembly according to another embodiment of the present invention.

FIG. 18A is a cross-sectional view of an optical collimating assembly according to another embodiment of the present invention.

FIG. 18B is a cross-sectional view of an optical collimating assembly according to another embodiment of the present invention.

FIG. 19 is a cross-sectional view of an optical collimating assembly according to another embodiment of the present invention.

FIG. 20 is a cross-sectional view of an optical collimating assembly according to another embodiment of the present invention.

FIG. 21 is a schematic view of a reflective element cut molded body of an optical collimating assembly according to one embodiment of the present invention.

FIG. 22 is a cross-sectional view of an optical collimating assembly according to one embodiment of the present invention.

FIG. 23 is a schematic view of a structured light projection device, according to one embodiment of the present invention.

FIG. 24 is a schematic view of a structured light projection device according to another embodiment of the present invention.

FIG. 25 is a schematic view of a structured light projection device according to another embodiment of the present invention.

FIG. 26 is a schematic view of a structured light projection device according to another embodiment of the present invention.

FIG. 27 is a schematic view of a structured light projection device according to another embodiment of the present invention.

FIG. 28 is a schematic top view of a structured light projection device, according to another embodiment of the invention.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be in a particular orientation, constructed and operated in a particular orientation, and thus the above terms are not to be construed as limiting the present invention.

It is understood that the terms "a" and "an" should be interpreted as meaning that a number of one element or element is one in one embodiment, while a number of other elements is one in another embodiment, and the terms "a" and "an" should not be interpreted as limiting the number.

Referring to fig. 1-15, an optical collimating assembly for a structured light projection device and a method of making the same according to the present invention is illustrated. The optical collimating assembly 10 has a small reduction size, especially a small height size, using the condition that the optical path of the reflecting element is not changed, and is suitable for the development of the current miniaturization requirement. Meanwhile, the optical alignment assembly is of a solid structure, is high in structural strength, and is not easy to disperse and generate displacement or deformation due to impact force. The optical alignment assembly manufacturing method is used for manufacturing the optical alignment assembly 10, and has low requirements on manufacturing processes and high product yield.

FIG. 8 is a flow chart of a method of manufacturing an optical alignment assembly according to the present invention.

Step 101: a light-transmissive medium 100 is provided, wherein a first surface 110 and a second surface 120 of the light-transmissive medium 100 are opposite and parallel.

As shown in fig. 1, the light-transmitting medium 100 may be a solid transparent medium such as transparent glass, but the invention is not limited thereto. The distance D between the first surface and the second surface is not limited, and can be designed by those skilled in the art according to the requirement. The technology of forming light-transmitting media with relatively parallel faces is currently well established. Taking glass as an example, it can be formed by a grinding process or by using a mold in the manufacturing process, etc., and will not be described herein. Preferably, the light-transmitting medium 100 has a refractive index greater than 1.

Step 102: a first reflective surface 130 and a second reflective surface 140 are formed on the first surface 110 and the second surface 120, respectively.

As shown in fig. 2A to 2D, the first light-transmitting medium reflective surface 130 and the second light-transmitting medium reflective surface 140 may be formed by covering a material with a light-reflecting property on the first surface 110 and the second surface 120 by sputtering or evaporation. The first light-transmitting medium reflecting surface 130 and the second light-transmitting medium reflecting surface 140 are surfaces of a light-reflecting material in contact with the light-transmitting medium 100.

Because the first surface 110 and the second surface 120 are opposite and parallel, the transmissive medium first reflective surface 130 and the transmissive medium second reflective surface 140 are also opposite and parallel. At this time, the first reflective surface 130 of the transparent medium and the second reflective surface 140 of the transparent medium are formed by adhering to the transparent medium 100, so that the requirement for the manufacturing process is reduced, no additional substrate is required to ensure the parallelism between the reflective surfaces, and errors caused by additional assembling steps are avoided.

Specifically, in the implementation process of step 102, the first surface 110 and the second surface 120 may be coated sequentially (as shown in fig. 2A), or the first surface 110 and the second surface 120 may be coated simultaneously (as shown in fig. 2B), which is not limited in the present invention. Alternatively, each side of the light-transmitting medium 100 may be coated (as shown in fig. 2D).

Step 103: a molding layer 200 is formed encasing the light-transmissive medium 100 having the light-transmissive medium first reflective surface 130 and the light-transmissive medium second reflective surface 140.

The molding layer 200 is formed on the surface of the light-transmitting medium 100 by a molding, die pressing, or injection molding process. The molding layer 200 is made of an opaque material, so as to prevent the reflective element 11 of the optical collimating assembly 10 formed subsequently from shielding unnecessary stray light, as shown in fig. 3A and 3B.

Step 104: the light-transmitting medium 100 with the molding layer 200 is cut at a predetermined interval to form a plurality of light-transmitting single stripes 150.

As shown in fig. 4, is an implementation of step 104. It can be known that, since the light-transmitting medium 100 has the light-transmitting medium first reflecting surface 130 and the light-transmitting medium second reflecting surface 140 which are opposite and parallel, after being cut, the resulting light-transmitting single strip 150 should also have a light-transmitting single strip first reflecting surface 152 and a single strip light-transmitting second reflecting surface 153, which are formed by cutting the light-transmitting medium first reflecting surface 130 and the light-transmitting medium second reflecting surface 140, at corresponding positions. The first reflective surface 152 and the second reflective surface 153 are opposite and parallel.

And setting a preset cutting distance according to the final product requirement of the optical alignment assembly 10. After cutting, the light-transmitting monomer 150 has at least one cut surface 151 that is not covered by the molding material. For example, the light-transmitting single body 150 at both ends has one of the cut surfaces 151, and the other light-transmitting single body 150 has two of the cut surfaces 151. The cutting surface 151 is also formed along the cutting line of step 104.

Step 105: the cut faces 151 of the light-transmitting single strip 150 are treated to prevent stray light from entering.

The method for processing the cut surface 151 of the single transparent strip 150 is various, for example, the cut surface 151 is roughened to make the cut surface 151 have a certain roughness, so as to prevent stray light from entering; or for example, a light shielding material is covered on the surface of the cutting surface 151, that is, a light shielding surface is formed, so as to achieve the purpose of preventing stray light from entering, and the like, which is not limited by the invention, as shown in fig. 5.

Step 106: the light-transmitting single strips 150 are arranged in a preset direction, the light-transmitting single strips 150 are cut and arranged according to preset cutting lines, a plurality of reflecting elements 11 with incident surfaces 111 and emergent surfaces 112 are formed, a preset included angle is formed between the extending direction of the light-transmitting single strips 150 and the extending direction of the cutting lines, light beams enter the reflecting elements 112 from the incident surfaces 111, and the light beams are reflected at least once by the reflecting elements 11 and then are emitted from the emergent surfaces 112.

The predetermined angle is related to the desired beam path, as shown in fig. 22. That is, the light path requirements are realized according to reflection, for example, the focus of the optical lens in the projection module is ensured to be located on the surface of the projection unit, or the light path requirement in the receiving module is ensured to meet the requirements of the back focal length or the total focal length of the module, and the preset included angles are correspondingly different. The incident surface 111 and the exit surface 112 are both surfaces exposed when the corresponding reflective elements 11 are cut and formed. That is, the incident surface 111 and the exit surface 112 are formed along the cut path of the single light-transmitting strip 150. It is worth mentioning that the distance between the predetermined cutting lines determines the size of the reflective element 11, in particular the height when mounted for use, and the skilled person can design the distance of the cutting lines according to the size requirement.

In one embodiment of the present invention, as shown in fig. 6A, the transparent single strip 150 is placed horizontally, that is, the transparent single strip 150 extends horizontally, and the predetermined cutting direction forms a predetermined included angle with the extending direction of the transparent single strip 150, so that the transparent single strip 150 is cut obliquely. In another embodiment of the present invention, as shown in fig. 6B, the transparent single strip 150 is obliquely disposed, that is, the extending direction of the transparent 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.

The reflective element 11 cut by the aforementioned method is shown in fig. 6C and 6D, and the cross section of the reflective element 11 is a parallelogram. Since the single light-transmitting strip 150 has the first reflecting surface 152 and the second reflecting surface 153 which are opposite and parallel, the cut reflecting element 11 should also have the first reflecting surface 113 and the second reflecting surface 114 which are cut and formed at corresponding positions, and the first reflecting surface 113 and the second reflecting surface 114 are opposite and parallel. The incident surface 111 and the exit surface 112 of the reflective element 11 formed along the cutting line are parallel to each other. That is, the first and second reflecting

surfaces

113 and 114 are inclined with respect to the incident surface 111 and the exit surface 112.

After the reflective element 11 is formed, two optical lenses 12 may be individually mounted on the predetermined regions of the incident surface 111 and the exit surface 112, respectively, to form the optical collimating assembly 10, as shown in fig. 7. That is, one of the optical lenses 12 is directly attached to a predetermined region of the incident surface 111, and the other optical lens 12 is directly disposed on a predetermined region of the emergent surface 112. The light beam enters the reflection element 11 from the optical lens 12 of the incident surface 111, is reflected at least twice by the first reflection surface 113 and the second reflection surface 114 which are parallel to each other, and exits from the optical lens 12 of the exit surface 112, and the incident light beam and the exit light beam are parallel.

In another embodiment of the present invention, the optical lens 12 is disposed on the surface of the reflective element 11 by a plate splicing process. FIG. 15 is a flow chart of optical lens and reflective element assembly according to one embodiment of the present invention. Specifically, after said step 105, the following steps may be performed to achieve the optical lens and reflective element assembly.

Step 201: the transparent single strips 150 are arranged on the substrate 300 according to a preset direction.

The substrate 300 may be a material suitable for post-cutting, such as glass or ceramic, as shown in fig. 9.

In one embodiment of the present invention, the step 210 can simultaneously achieve the purpose of the step 105, i.e. achieve the anti-parasitic treatment step. Specifically, the single transparent strip 150 is arranged on the substrate 300 in such a manner that the cutting surface 151 is attached to the substrate 300. The substrate 300 may be made of an opaque material. Further, for the single light-transmitting strip 150 of the two cutting surfaces 151, two opposite substrates 300 may be adopted, that is, the single light-transmitting strip 150 is arranged between the two opposite substrates 300 in a manner that each cutting surface 151 is attached to the corresponding substrate 300.

Step 202: the transparent single strip 150 and the substrate 300 cut according to the preset cutting line form a plurality of reflective element strips 160, wherein the extending direction of the transparent single strip 150 and the extending direction of the cutting line form a preset included angle, and the reflective element strips 160 comprise a substrate strip 310 and a plurality of reflective elements 11 arranged on the substrate strip 310 and having an incident surface 111 and an exit surface 112.

As mentioned above, the arrangement direction of the single transparent strip 150 can be horizontal and can be inclined, and the corresponding direction of the cutting line can be changed accordingly. The light-transmissive single strip 150 is cut to form a plurality of the reflective elements 11. Since the single transparent strip 150 is attached to the substrate 300, the substrate 300 is correspondingly cut, and the reflective elements 11 are correspondingly attached to the substrate strip 310 formed by cutting the substrate 300, as shown in fig. 10. Fig. 10 is a view of the cut reflective element strips 160 of fig. 9 rotated 90 degrees.

Step 203: at least one optical lens imposition 400 is provided.

As shown in fig. 11A and 11B, a plurality of optical lenses 12 are arranged in an array on a transparent substrate 410 to form the optical lens imposition 400. The arrangement of the optical lenses 12 in the optical lens imposition 100 corresponds to the arrangement of the reflective elements 11 in the reflective element strip 160, for example, the pitch between the adjacent optical lenses 12 in the same row is equal to the pitch between the adjacent reflective elements 11. The optical lens imposition 400 may be a strip shape corresponding to the size of the reflective element strips 160, or may be a plate shape capable of covering a plurality of reflective element strips 160.

Step 204: the reflection element strips 160 are arranged according to the spacing between adjacent rows of the optical lenses 12 of the optical lens imposition 400, wherein the incident surface 111 or the exit surface 112 of the reflection element 11 faces outward.

In order to facilitate the subsequent assembly of the optical lens imposition 400 and the reflective element strips 160, the arrangement of the reflective element strips 160 corresponds to the arrangement of the optical lenses 12 of the optical lens imposition 400, so that the optical lenses 12 can be installed in the preset area of the incident surface 111 or the emergent surface 112 in the subsequent assembly process.

Step 205: the light-transmitting substrate 410 of the optical lens imposition 400 is attached to the incident surface 111 or the exit surface 112 of the reflective element 11 of the reflective element strip 160, wherein the optical lens 12 corresponds to a predetermined region of the incident surface 111 or/and the exit surface 112.

That is, the optical lens 12 is disposed on the transparent substrate 410, and the transparent substrate 410 is attached to the incident surface 111 or the emitting surface 112 of the reflective element 11. Unlike the solution in which the optical lens 12 is directly attached to the incident surface 111 or the exit surface 112, the mounting of the optical lens 12 by using a transparent substrate in the imposition process can improve the assembly efficiency, as shown in fig. 12.

Optional step 206: the base strip 310 of the reflective element strips 160 is removed.

Step 206 is an optional step, and the base-strip 310 need not be removed when the base-strip 310 is used as an anti-glare treatment element. In embodiments where the anti-glare treatment has been performed using a roughening step, the step 206 may be performed to reduce bulk.

Step 207: the assembled optical lens imposition 400 and the reflective element strips 160 are divided to form a plurality of the optical collimating assemblies 10.

The order of the step 206 and the step 207 is not limited. Step 206 may be performed before step 207 is performed, that is, the substrate strip 310 of the reflective element strip 160 is removed, and then the transparent substrate 410 of the optical lens imposition 400 is cut. Alternatively, step 207 may be performed first, and step 206 is performed, that is, a cutting process is performed to cut the transparent substrate 410 of the optical lens imposition 400 and the substrate strips 310 of the reflective element strips 160, and then the substrate strips of each optical alignment assembly 10 may be removed one by one.

The optical alignment assembly 10 assembled and cut according to the imposition process described above is shown in fig. 13 and 17. The cross section of the reflecting 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 surfaces of the incident surface 111 or the exit surface 112 of the corresponding reflective element 11. Specifically, one of the transparent sub-substrates 13 is attached to the surface of the incident surface 111 of the reflective element 11, and one of the optical lenses 12 is attached to the surface of the transparent sub-substrate 13, corresponding to a predetermined region of the incident surface 111. Another transparent sub-substrate 13 is attached to the surface of the exit surface 112 of the reflective element 11, and another optical lens 12 is attached to the surface of the other transparent sub-substrate 13, corresponding to a predetermined region of the exit surface 112.

The light beam enters the reflection element 11 from the optical lens 12 on the incident surface 111 side through the transparent sub-substrate 13 on the incident surface 111 side, is reflected at least twice by the first reflection surface 113 and the second reflection surface 114 which are parallel to each other, passes through the transparent sub-substrate 13 on the exit surface 112 side, and is emitted from the optical lens 12 on the exit surface 112, and the incident light beam and the exit light beam are parallel.

In another embodiment of the present invention, in the step 106, the single transparent strip 150 is cut twice, and the cutting directions of the two times are perpendicular, as shown in fig. 14A. For example, the single strip 150 is positioned horizontally, i.e., the single strip 150 extends horizontally. The two preset cutting directions form a preset included angle with the extending direction of the light-transmitting single strip 150, the light-transmitting single strip 150 is obliquely cut, and the two preset cutting directions are mutually perpendicular.

The reflective member 11A obtained by the method described above is shown in fig. 14B, and the cross section of the reflective member 11A is square. After two cuts perpendicular to each other, the reflective element 11A has a first reflective surface 113A, and the first reflective surface 113A extends along a diagonal of the reflective element 11A. Further, the incident surface 111A and the exit surface 112A formed in 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 reflecting element 11A from the incident surface 111A, is reflected once by the first reflecting surfaces 113A parallel to each other, i.e., is emitted from the emitting surface 112A, and the incident light beam and the emitting light beam are perpendicular. The reflective element 11A may be used in a periscopic module.

The shape of the final reflecting element 11 is determined by different cutting methods, and the skilled person can design the cutting scheme according to the requirement. However, it can be understood that, no matter how the cutting is performed, since the surface having the reflection function is attached to a transparent medium or the like, and an additional assembly step is not required, not only the structural strength is large, but also the process requirement is low. Taking the manufacturing scheme proposed in the background art as an example, in the prior art, a substrate is provided first, a reflective structure (reflective substrate) is formed on the surface of the substrate by coating, two reflective structures are arranged face to face, the middle is separated by a spacer to form a reflective cavity, and then the substrate is removed. The reflecting substrates are arranged face to face, the distance D between the reflecting substrates is determined by the spacing pieces, and the spacing pieces are ensured to be parallel, so that the heights of all the spacing pieces are consistent and the surfaces of the spacing pieces are smooth; further, when the spacers are placed between the reflective substrates, the distance between the spacers needs to be set according to a predetermined position, and once the predetermined position is shifted, the optical element cannot be normally used.

According to the invention, the reflecting film is coated on the light-transmitting medium, and then the light-transmitting medium is molded, for example, when the light-transmitting medium is implemented as glass, the first surface and the second surface of the glass can be kept parallel through a grinding technology, namely, the flatness is kept high, so that the process difficulty is reduced. The part of the peripheral wall of the reflecting element is formed by molding process, roughening process and the like, so that the process is mature, the process requirement is low, and errors are not easy to cause. While prior art solutions are prone to errors such as parallelism errors between substrates and distance errors between spacers, the glass formation of the present invention ensures flatness, with only focus on distance accuracy during cutting.

It is noted that the shape of the optical element may be modified to facilitate the optical element, for example, by cutting the molded body to form a cubic structure, as shown in fig. 21.

According to another aspect of the invention, the invention further provides an optical collimating assembly for a structured light projection device. The optical collimating assembly can be produced using the optical collimating assembly manufacturing method described above to achieve the objects and advantages of the present invention.

As shown in fig. 16, the optical collimating assembly 10 includes the reflective element 11 and at least one optical lens 12. The reflective element 11 comprises a reflective body 115 and a molded body 116. The reflective body 115 is made of a solid light-transmitting medium. The reflection body 115 has two reflection surfaces, i.e., 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 reflective surface 113 and the second reflective surface 114 may be formed by covering a surface of a light-transmitting medium with a reflective material. The reflection body 115 further has the incident surface 111 and the 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. The molded body 116 covers the first reflecting surface 113 and the second reflecting surface 114, and the molded body 116 surrounds the incident surface 111 and the exit surface 112.

Further, the reflection main body 115 has a six-sided three-dimensional structure, in which 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, and the reflection main body can be implemented by performing surface roughening treatment, coating a light shielding material or attaching a light shielding plate.

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

Alternatively, in another embodiment of the present invention, as shown in FIG. 17, the optical collimating assembly 10 further comprises at least one transparent submount 13. The light-transmissive submount 13 is made of a light-transmissive material. The light-transmitting sub-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 transparent sub-substrate 13, and corresponds to a predetermined region of the incident surface 111 or the exit surface 112. Preferably, one of the transparent sub-substrates 13 is attached to the surface of the incident surface 111 of the reflective element 11, and one of the optical lenses 12 is attached to the surface of the transparent sub-substrate 13, corresponding to a predetermined region of the incident surface 111. Another transparent sub-substrate 13 is attached to the surface of the exit surface 112 of the reflective element 11, and another optical lens 12 is attached to the surface of the other transparent sub-substrate 13, corresponding to a predetermined region of the exit surface 112.

In another embodiment of the present invention, as shown in FIG. 18A, the optical collimating assembly 10B includes a reflective element 11B. The reflecting element 11B includes the reflecting body 115B and the molded body 116B, and the reflecting body 115B has two reflecting surfaces, i.e., the first reflecting surface 113B and the second reflecting surface 114B, the incident surface 111B, and the exit surface 112B. In contrast to the previous exemplary embodiments, the first reflection surface 113B and the second reflection surface 114B are each embodied as a free-form surface. The reflecting element 11B collimates the light beam directly through the free curved surface, so the optical lens can be eliminated in this embodiment. It should be noted that, since the first reflective surface 113B and the second reflective surface 114B are designed as the free-form surfaces, the transparent medium 100 directly forms the corresponding free-form surfaces in the manufacturing process of the reflective element, for example, when the transparent medium 100 is implemented as glass, the transparent medium 100 can be directly molded to form a module with the free-form surfaces, and then the reflective surfaces are coated.

Preferably, the reflecting element 11B has a turning angle α of 50 ° to 75 °. Taking the turning angle α as 60 °, the incident angle and the reflection angle of the light beam entering the reflection body 115B and reflected by the first reflection surface 113B or the second reflection surface 114B are also preferably 60 °, so that the light beam is better collimated. In other words, it is preferable that the incident angle and the reflection angle at which the light beam is reflected are equal to the angle of the turning angle of the reflecting element 11B.

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 beams on the first reflecting surface 113B and the second reflecting surface 114B are equal, it is ensured that the light beams enter from the incident surface 111B perpendicularly and exit from the exit surface 112B perpendicularly, so that the outgoing light and the incoming light passing through the optical collimating assembly 10B are kept parallel.

Compared with a flat reflecting surface design, the coating of the free-form surface is easier. Secondly, the design of the free curved surface enables the horizontal displacement to be insensitive, and the assembly difficulty is reduced. In the embodiment of the invention, as for the whole structured light projection device, the optical lens is eliminated, so that the light tilt can be controlled more easily. The less the light beam penetrates through the device, the lower and less the brightness of the device is, the higher the efficiency is, and the power of the projection unit can be reduced to a certain degree; further, uniformity of luminance can be ensured. Of course, the optical collimating assembly 10B may further include at least one optical lens 12B for further collimating. The optical lens 12B is disposed in a predetermined region of the incident surface 111B or the exit surface 112B, so that the free-form surface and the optical lens collimate the light beam, so that the light beam collimation effect is better, as shown in fig. 18B.

Different cutting patterns may be different to obtain the reflective element, and fig. 19 is a structural diagram of another optical alignment assembly according to the present invention. The optical collimating assembly 10A includes the reflective element 11A and at least one of the optical lenses 12A. The reflective element 11A includes a reflective body 115A and a molded body 116A.

Unlike the previous embodiment, the reflective body 115A has the first reflective surface 113A. That is, the reflecting body 115A has only one reflecting surface. The first reflective surface 113A is formed by cutting after the surface of the light-transmitting medium is covered with a reflective material. 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 reflecting surface 113A faces the incident surface 111A and the exit surface 112A. The molded body 116A covers the first reflective surface 113A.

That is, the cross section of the reflecting element 11A is square. The first reflecting surface 113A extends along a diagonal of the reflecting element 11A. The light beam enters the reflective element 11A from the incident surface 111A, is reflected once by the first reflective surface 113A, and is emitted from the emitting surface 112A, and the incident light beam and the emitting light beam are perpendicular. The reflective element 11A may be used in an edge-emitting structured light module, and the reflective element 11A collimates light emitted by an edge-emitting laser and turns a light path.

It is worth mentioning that in some special projection configurations, the incident light and the emergent light are required to be not parallel, and correspondingly, the first reflective surface 113 and the second reflective surface 114 are not parallel, as shown in fig. 20. The relative inclination of the first reflecting surface 113 and the second reflecting surface 114 is set according to a preset path of the light beam. The first reflective surface 113 and the second reflective surface 114 that are not parallel to each other only need to be correspondingly disposed on the first surface and the second surface of the light-transmitting medium 100, and may be implemented by processes such as grinding and molding, and details are not described here.

According to another aspect of the present invention, the optical collimating assembly of the present invention can be applied to a structured light projection device, achieving the objects and advantages of the present invention, as shown in fig. 23-28.

Specifically, the structured light projection device includes the optical collimating assembly 10, an optical diffraction element 20, and a projection unit 30. The optical collimating assembly 10 is disposed between the projection unit 30 and the optical diffraction element 20. The projection unit 30 emits a light beam, which is collimated by the optical collimating assembly 10, and then is diffracted or replicated by the optical diffraction element 20, and then is projected onto a spatial target surface. The projection unit 30 may 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 a plurality of light beams. The optical collimating assembly 10 may be configured as any of the above structures, the first reflective surface and the second reflective surface may be flat surfaces or free curved surfaces, the optical lens may be directly attached to the incident surface and the reflective surface, or a light-transmissive substrate structure may be used, which is not limited herein. The optical diffraction element 20 may have a single-layer structure (as shown in fig. 23) or a double-layer structure (as shown in fig. 24), but the present invention is not limited thereto.

In one embodiment, in order to improve the collimation effect of the structured light projection device, as shown in fig. 25, the optical diffraction element 20 includes a collimation portion 21 and a diffraction portion 22. The light beam collimated by the optical collimating assembly 10 is further collimated by the collimating unit 21, and then reaches the spatial target through the diffraction unit 22. The diffraction unit 22 is provided on the light beam emission side of the collimation unit 21, and diffracts and expands the light beam that has passed through the re-collimation. Preferably, the optical diffraction element 20 is implemented as a superlens. Preferably, the collimating part is provided as a convex lens or a fresnel lens so that collimation can be performed. It should be noted that, in this embodiment, the positional relationship between the collimating section 21 and the diffraction section 22 is not limited, and the collimating section 21 may be arranged on the light beam emitting side of the diffraction section 22 by performing diffraction and then collimation.

In one embodiment of the present invention, as shown in fig. 26-28, 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 40 board and is electrically connected to the circuit board 40. The projection unit 30 projects a light beam, which is received and collimated by the optical collimating assembly 10, and then diffracted and expanded by the optical diffraction element 20, and then projected to a spatial target. Since the projection unit 30 is implemented as a VCSEL and the projection energy is large, especially the zero-order problem may cause damage to the human eye, it is necessary to avoid the occurrence of zero-order diffraction or avoid the light beam directly reaching the human eye without diffraction, and therefore it is necessary to ensure the structural integrity of the optical diffraction element 30, and 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.

The detection circuit 50 is preferably implemented as ITO (indium tin oxide) plated on the surface of the optical diffraction element 20. The detection circuit 50 is electrically connected to the circuit board 40, and detects the optical diffraction element 20. For example, the ITO is plated on the surface of the optical diffraction element 20 to form a capacitor structure. When the surface of the optical diffraction element 20 is damaged or has water vapor or water drops, the capacitance value of the capacitor structure changes, so that the corresponding processor judges that the optical diffraction element 20 is abnormal, and the work of the structured light projection device is interrupted, thereby ensuring the safety of human eyes. The detection circuit 50 may be made of other materials (preferably transparent materials) and may detect the signal by means of resistance, inductance, or the like.

It should be noted that the detecting circuit 50 needs to be conducted to the circuit board 40, and therefore, in this embodiment of the invention, an LDS (Laser Direct Structuring) process is further adopted on the surface of the optical reflection element 10 to form a conducting circuit 60, and the conducting circuit 60 enables the detecting circuit 50 to be conducted to the circuit board 40. It should be noted that, in the prior art, when the sidewall of the reflective element is made of glass or other substrates, the LDS cannot be used to form a circuit. A circuit structure is usually externally arranged, thereby increasing the size of the whole projection module. However, in the present invention, since the reflective element is formed by a molding process and the LDS process can be performed on a molding material, the conductive circuit 60 can be disposed on the surface of the molding body 116 by the LDS process, so that no additional circuit is required, the process difficulty is reduced, and the overall volume of the projection module is reduced.

Alternatively, the conduction circuit 60 is implemented as a conductive member. In the manufacturing process, a plurality of conductive members are arranged in advance, the conductive members are wrapped in the molding layer 200 after molding and injection molding are completed, and the detection circuit 50 is communicated with the circuit board 40 through the conductive members.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.

Claims

1. A reflective element, comprising:

2. The reflective element of claim 1, wherein the reflective surface is formed by coating a surface of a light transmissive medium with a reflective material.

3. The reflective element of claim 1, further comprising two reflective surfaces of the reflective body, wherein the two reflective surfaces are opposite and parallel and are inclined with respect to the incident surface and the exit surface, such that the light beam enters the reflective element from the incident surface, is reflected at least twice by the reflective surfaces, and exits the exit surface, such that the incident light beam and the exit light beam are parallel.

4. The reflective element of claim 3, wherein the entrance face and the exit face are opposite and parallel, the reflective element having a parallelogram in cross-section.

5. A reflective element according to claim 3, wherein both of the reflective surfaces are implemented as flat surfaces.

6. The reflective element according to claim 3, wherein both of the reflective surfaces are implemented as free-form surfaces.

7. The reflective element of claim 6, wherein the inflection angle of the free-form surface is 50 ° to 75 °.

8. The reflective element of claim 6, wherein the turning angle of the light beam on the free-form surface is 60 ° to 150 °.

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

10. The reflective element according to any one of claims 1 to 9, wherein the reflective body further comprises at least one anti-glare surface formed by any one of roughening the surface of the reflective body, coating a light-shielding material, or attaching a light-shielding plate.

11. An optical collimating assembly for use in a structured light projection device, comprising:

a reflective element as claimed in any one of claims 1 to 10; and

12. The optical collimating assembly of claim 11, further comprising at least one light transmissive submount, wherein the light transmissive submount is made of a light transmissive material, wherein the light transmissive submount is attached to the surface of the incident surface or \ and the exit surface, wherein the optical lens is attached to the surface of the light transmissive submount corresponding to a predetermined area of the incident surface or \ and the exit surface.

13. A structured light projection device, comprising:

a projection unit for emitting a light beam;

the optical collimating assembly of any of claims 11 or 12, wherein the optical collimating assembly collimates the light beam emitted by the projection unit; and

14. The structured light projection device of claim 13, wherein the optical diffraction element comprises a collimating part and a diffracting part, wherein the diffracting part is disposed on the light beam emitting side of the collimating part, so that the light beam collimated by the optical collimating component is further collimated by the collimating part and then reaches the spatial target through the diffracting part.

15. A structured light projection device according to claim 14, further comprising 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 wherein 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.

16. The structured light projection device of claim 15, wherein the detection circuitry is implemented as ITO, plated on the surface of the optical diffraction element.

17. The structured light projection device of claim 15, further comprising a continuity circuit, wherein the continuity circuit conducts the detection circuit and the wiring board, wherein the continuity circuit is formed on the surface of the molded body by performing an LDS process.

18. The structured light projection device of claim 15, further comprising a continuity circuit, wherein the continuity circuit conducts the detection circuit and the wiring board, wherein the continuity circuit is encapsulated by the molded body.

19. A method of making an optical collimating assembly for a structured light projection device, comprising:

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

(b) forming a molding layer wrapping the light-transmitting medium with the light-transmitting medium first reflecting surface and the light-transmitting medium second reflecting surface, wherein the molding layer is made of opaque materials;

20. The method of manufacturing an optical collimating assembly of claim 19 wherein step (a) forms the optically transmissive medium first reflective surface and the optically transmissive medium second reflective surface by covering the first surface and the second surface with a material having light reflecting properties.

21. The method of manufacturing an optical collimating assembly of claim 19 further comprising, prior to step (d):

22. The method of manufacturing an optical collimating assembly of claim 21 wherein step (e) forms the anti-glare surface by roughening the cutting surface.

23. The method of manufacturing an optical collimating assembly of claim 21 wherein said step (e) forms said light-shading prevention surface by covering a surface of said cut surface with a light-shading material.

24. The method of claim 21, wherein the light-transmissive strip in step (d) extends horizontally, the predetermined cutting direction forms a predetermined included angle with the extending direction of the light-transmissive strip, and the light-transmissive strip is cut obliquely.

25. The method of manufacturing an optical collimating assembly of claim 21 wherein in step (d) the transparent strips are placed obliquely with a predetermined cutting direction extending in a horizontal direction.

26. The method of manufacturing an optical collimating assembly of claim 19 wherein step (d) further comprises the steps of:

27. The method of manufacturing an optical collimating assembly of claim 19 further comprising:

28. The method of manufacturing an optical collimating assembly of claim 26 further comprising:

29. The method of manufacturing an optical collimating assembly of claim 28 further comprising:

(h) removing the base strip of the strips of reflective elements.

30. The method of manufacturing an optical collimating assembly of claim 28 or 29, further comprising:

31. The method for manufacturing an optical collimating assembly of claim 19, wherein the light transmitting strip in step (d) is cut twice, the two predetermined cutting directions are perpendicular, and the incident surface and the exit surface of the reflecting element are formed perpendicular, so that the light beam enters the reflecting element from the incident surface, is reflected once by the reflecting element, and then exits from the exit surface.

32. The method of manufacturing an optical collimating assembly of claim 19 wherein the first and second surfaces in step (a) are opposing and parallel free-form surfaces, wherein the entrance and exit surfaces formed by the cutting in step (d) are corresponding opposing and parallel free-form surfaces.

33. The method of manufacturing an optical collimating assembly of claim 32, wherein the turning angle of the free-form surfaces of the entrance face and the exit face is 50 ° to 75 °.

34. The method of manufacturing an optical collimating assembly of claim 26, wherein the transparent strips in step (d.1) are arranged on the substrate with their cut surfaces attached to the substrate.