Projection lens, light projector and depth camera module

Abstract

The application provides a projection lens, a light projector and a depth camera module, comprising a first lens, a second lens, a lamp mirror and a lens barrel; the first lens and the second lens are arranged on the light-in side of the lens barrel; the lamp mirror is arranged on the light-out side of the lens barrel; the first lens is used for converging and projecting a plurality of laser beams projected by a light source to the second lens; the second lens is used for converging and projecting the plurality of laser beams projected by the first lens to the light-in surface of the lamp mirror again; and the lamp mirror is used for making the plurality of incident laser beams parallel or close to parallel out. The application converges light rays to the lamp mirror through the first lens and the second lens, and makes the light diaphragm be located on the light-in surface of the lamp mirror, so that the depth camera module equipped with the projection lens is suitable to be installed in a narrow gap and will not be blocked FOV, for example, the application of the application on a narrow frame screen is realized, and the lamp mirror can also be closely attached to a mobile phone glass cover plate to play a dustproof role.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more specifically, to a projection lens, a light projector, and a depth camera module. Background Technology

[0002] As the market develops, consumers have increasingly stringent requirements for display effects, demanding not only diverse designs but also higher screen-to-body ratios. Full-screen technology, through ultra-narrow bezels or even borderless designs, achieves screen-to-body ratios exceeding 90%.

[0003] Full-screen phones maximize the display area without changing the body shape, resulting in a more stunning display effect. Existing full-screen structural designs have a non-display area, or notch, at the top of the display substrate to accommodate components such as the depth camera module in 3D camera modules. However, this still affects the aesthetics of the display device and the full-screen experience. Summary of the Invention

[0004] In view of this, the present invention provides a projection lens, a light projector, and a depth camera module to solve the problem that the non-display area of ​​the existing depth camera module affects the aesthetics of the display device and the full-screen experience.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] The projection lens provided by the present invention includes a first lens, a second lens, a lamp lens, and a lens barrel;

[0007] The first lens and the second lens are disposed on the light-incident side of the lens barrel; the lamp lens is disposed on the light-outceasing side of the lens barrel;

[0008] The first lens is used to converge multiple laser beams projected by the light source and project them onto the second lens;

[0009] The second lens is used to refocus the multiple laser beams projected by the first lens and project them onto the light-incident surface of the lamp mirror;

[0010] The lamp mirror is used to ensure that the incident multiple laser beams are emitted in parallel or nearly parallel.

[0011] Preferably, the light-incident side of the lamp mirror is provided with a concave light-incident opening;

[0012] The bottom surface of the light inlet is the light-incident surface; the light-incident surface is a convex surface; the aperture of the second lens is disposed on the convex surface;

[0013] The incident light surface is used to ensure that the incident multiple laser beams are emitted in parallel or nearly parallel.

[0014] Preferably, a spacer is provided between the first lens and the second lens.

[0015] Preferably, the light-emitting side of the lamp mirror is provided with a boss structure;

[0016] The end face of the boss structure is the light-emitting surface.

[0017] Preferably, the first lens and the second lens are convex lenses.

[0018] Preferably, the light-incident side of the lamp mirror is fitted to the second lens.

[0019] Preferably, a partition frame is provided on the lens barrel;

[0020] The second lens is disposed on one side of the partition frame, and the lens barrel is disposed on the other side of the partition frame.

[0021] Preferably, the lamp mirror is made of optical plastic material.

[0022] The light projector provided according to the present invention includes the aforementioned projection lens, and further includes a structured light projector;

[0023] The structured light projector is used to project structured light onto the projection lens, the structured light comprising multiple randomly distributed laser beams;

[0024] The projection lens is used to converge the multiple laser beams and incident them onto the light-incident surface of the lamp mirror, thereby causing the incident multiple laser beams to exit in parallel or nearly parallel through the lamp mirror.

[0025] The depth camera module provided according to the present invention includes a light projector and an imaging module.

[0026] The light projector is used to make the incident multiple laser beams exit in parallel or nearly parallel through the lamp lens so that the lasers illuminate the object to be photographed;

[0027] The imaging module is used to receive the laser reflected by the object to be photographed through another light-transmitting area, and to obtain a depth image of the surface of the object to be photographed based on the light spot pattern of the laser reflected by the object to be photographed.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] This invention uses a first lens and a second lens to focus light onto a lamp mirror, and positions the aperture on the light-incident surface of the lamp mirror. This allows a depth camera module with a projection lens to be installed in a narrow gap without obstructing the field of view (FOV). This invention can be applied to narrow-bezel screens (where the black matrix area is relatively narrow). It can also make the lamp mirror fit snugly against the phone's glass cover, providing dust protection. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the display device in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the display device in a modified embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of an installation of the laser module in an embodiment of the present invention;

[0034] Figure 4 This is another schematic diagram of the laser module installation in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the installation of the imaging module in an embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of an installation of the depth camera module in a variation of the present invention;

[0037] Figure 7 This is another installation diagram of the depth camera module in a variation of the present invention;

[0038] Figure 8 This is a schematic diagram of a display device based on an EEL laser in an embodiment of the present invention;

[0039] Figure 9 This is a schematic diagram of a display device based on a VCSEL laser in an embodiment of the present invention;

[0040] Figure 10 This is a schematic diagram of the structure of a display device provided in the first specific embodiment of the present invention;

[0041] Figure 11 This is a schematic diagram of the structure of a display device provided in a second specific embodiment of the present invention;

[0042] Figure 12 This is a schematic diagram of a projection lens according to an embodiment of the present invention;

[0043] Figure 13 This is a schematic diagram of another structure of the projection lens according to an embodiment of the present invention;

[0044] Figure 14 This is a laser spot diagram of a multi-beam laser according to an embodiment of the present invention.

[0045] In the picture:

[0046] 10 is the display substrate; 11 is the laser module; 12 is the imaging module; 1201 is the second lamp lens; 1202 is the receiving lens; 1203 is the photodetector array; 13 is the beam splitter; 14 is the driving circuit; 15 is the processing module; 16 is the lens assembly; 1601 is the first lens; 1602 is the second lens; 1603 is the spacer; 1604 is the lens barrel; 1605 is the frame; 17 is the reflector; 18 is the collimating lens; 19 is the first lamp lens; 20 is the black matrix area; 30 is the display area; 40 is the inner screen. Detailed Implementation

[0047] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0048] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be for both fixing and circuit connection purposes.

[0049] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0051] As described in the background section, existing full-screen-based structural designs have a non-display area, or notch area, on the top of the display substrate in order to install devices such as depth camera modules in 3D camera modules. However, this affects the aesthetics of the display device and the full-screen experience.

[0052] The inventors discovered that existing depth camera modules all use vertical cavity surface emitting lasers (VCSELs) as light sources. However, due to the low output power of VCSEL lasers, when the transmittance of the display substrate is low, the light power of the laser passing through the display panel is low, and an effective depth image cannot be obtained. Therefore, it is necessary to set a non-display area, i.e., a notch area, on the top of the display substrate, and to drill holes in the non-display area to install the VCSEL laser.

[0053] Based on this, the present invention provides a projection lens, a light projector, and a depth camera module to overcome the above-mentioned problems existing in the prior art, including a first lens, a second lens, a lamp lens, and a lens barrel;

[0054] The first lens and the second lens are disposed on the light-incident side of the lens barrel; the lamp lens is disposed on the light-outceasing side of the lens barrel;

[0055] The first lens is used to converge multiple laser beams projected by the light source and project them onto the second lens;

[0056] The second lens is used to refocus the multiple laser beams projected by the first lens and project them onto the light-incident surface of the lamp mirror;

[0057] The lamp mirror is used to ensure that the incident multiple laser beams are emitted in parallel or nearly parallel.

[0058] The present invention uses a first lens and a second lens to focus light onto the lamp mirror and positions the aperture on the light-incident surface of the lamp mirror, making it suitable for mounting a depth camera module with a projection lens in a narrow gap without obstructing the field of view (FOV). This invention can be applied to narrow bezel screens (where the black matrix area is relatively narrow) and can also make the lamp mirror fit snugly against the phone's glass cover, thus providing dust protection.

[0059] The above is the core idea of ​​this invention. To make the above-mentioned objectives, features, and advantages of this invention more apparent and understandable, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0060] This invention provides a display device with a 3D camera module, such as... Figure 1 As shown, the system includes a display substrate 10 and a 3D camera module, which includes a depth camera module located on the backlight side of the display substrate 10. It should be noted that the depth camera module in this embodiment is an infrared camera module, and the laser module uses an infrared laser that emits infrared laser light. The laser module employs a vertical-cavity surface-emitting laser array, an edge-emitting laser, and a semiconductor laser.

[0061] In this embodiment, the light-emitting side of the display substrate is the side that can display images, while the backlight side is the side that cannot display images. That is, the depth camera module in this embodiment can be located below the display substrate 10, i.e., below the screen, without damaging the structure of the display substrate 10; for example, it does not require drilling a hole in the non-display area at the top of the display substrate 10 to house the depth camera module. The display substrate includes a display area and a black matrix area surrounding the display area; the black matrix area includes at least two light-transmitting areas. The light-transmitting areas are circular areas with a diameter of less than 1 mm.

[0062] In this embodiment of the invention, the depth camera module includes a laser module 11 and an imaging module 12. Both the laser module 11 and the imaging module 12 are located on the backlight side of the display substrate 10. The light-emitting port of the laser module 11 faces the display substrate 10, allowing the laser to pass through a light-transmitting area and illuminate the object to be photographed on the light-emitting side of the display substrate 10. The light-inlet port of the imaging module 12 faces the display substrate 10, allowing the laser reflected from the object to pass through another light-transmitting area before entering the imaging module 12.

[0063] The laser module 11 includes a structured light projector and a projection lens; the projection lens includes a lens assembly 16 and a first lamp mirror 19; the structured light projector projects structured light onto the lens assembly, the structured light including multiple randomly distributed laser beams; the lens assembly 16 converges the multiple laser beams and incident them onto the light-incident surface of the first lamp mirror; the first lamp mirror 19 ensures that the incident multiple laser beams exit in parallel or nearly parallel so that the laser beams pass through a light-transmitting area and illuminate the object to be photographed.

[0064] The imaging module 12 is used to receive the laser light reflected from the object to be photographed through another light-transmitting area, and to obtain a depth image of the surface of the object to be photographed based on the light spot pattern of the laser light reflected from the object. This depth image includes depth information of different regions on the surface of the object to be photographed.

[0065] Since the laser module 11 and the imaging module 12 are located on the backlight side of the black matrix area, there is no need to set a non-display area on the top of the display device to install the depth camera module, thus not affecting the aesthetics of the display device and the full-screen experience.

[0066] Furthermore, since both the laser module 11 and the imaging module 12 are located on the backlight side of the display substrate 10, there are multiple possibilities for their arrangement and combination. Without affecting aesthetics, the distance between the laser module 11 and the imaging module 12 can be increased to improve the shooting accuracy of the depth camera module, such as... Figure 2 As shown, the laser module 11 and the imaging module 12 can also be set in the black matrix areas on both sides respectively.

[0067] Optionally, the light-transmitting area is provided with an infrared film layer;

[0068] The first lamp lens 19 is used to make the divergent incident multiple laser beams exit in parallel or nearly parallel so that the laser beams pass through an infrared film layer and a light-transmitting area to illuminate the object to be photographed.

[0069] The imaging module 12 employs an infrared camera to receive infrared laser light reflected from the object to be photographed through another infrared film layer and another light-transmitting area, and to obtain a depth image of the surface of the object to be photographed based on the infrared laser light.

[0070] Optionally, such as Figure 3 , Figure 6 , Figure 10 As shown, the laser module includes a beam splitter located between the structured light projector and the projection lens;

[0071] The structured light projector uses a laser array 1101 to project a dot matrix laser.

[0072] The beam splitter 13 is located on the light-emitting side of the laser array 1101 and is used to split the dot matrix laser emitted by the structured light projector into multiple randomly distributed laser beams.

[0073] In this embodiment of the invention, the display substrate 10 can be a glass substrate, and the inner side of the display substrate 10 is the inner screen 40 of the display device.

[0074] In the embodiments of the present invention, such as Figure 8 and Figure 9 As shown, the depth camera module includes a drive circuit 14 connected to a laser module 11 and an imaging module 12. This drive circuit 14 controls the simultaneous on / off operation of the laser module 11 and the imaging module 12, and controls the output optical power of the laser module 11 by controlling the drive current of the laser module 11, thereby controlling the optical power of the laser passing through a light-transmitting region.

[0075] Furthermore, the depth camera module also includes a processing module 15, and the 3D camera module also includes a 2D imaging module. The 2D imaging module is used to capture 2D images of the object to be photographed. The processing module 15 is used to obtain a 3D image of the object to be photographed based on the depth image captured by the 3D camera module and the 2D image captured by the 2D imaging module.

[0076] It should be noted that in order to place the depth camera module on the backlight side of the display substrate 10, the driving current can be increased by the driving circuit 14, the pulse width of the laser module 11 can be reduced, the optical power of the laser module 11 can be greatly increased, and the total pulse energy of the laser module 11 can be kept basically unchanged, thus meeting the optical power limit for human eye safety.

[0077] In one embodiment of the present invention, such as Figure 4 , Figure 7 , Figure 11 As shown, the structured light projector includes an edge-emitting laser 1102, a collimating lens 18, a reflecting device 17, and a beam splitter 13 located between the laser module and the projection lens; the beam splitter 13 and the laser module 11 are also provided with the collimating lens 18 and the reflecting device 17.

[0078] The side-emitting laser 1102 is used to project laser light onto the collimating lens;

[0079] The collimating lens 18 is located on the light-emitting side of the edge-emitting laser 1102, and is used to collimate the incident laser and emit a collimated beam.

[0080] The reflective device 17 is located on the light-emitting side of the collimating lens 18 and is used to refract the collimated beam and project it onto the beam splitter 13.

[0081] The beam splitter 13 is located on the light-emitting side of the reflector 17 and is used to split the collimated beam projected by the reflector 17 into multiple randomly distributed laser beams.

[0082] Specifically, the beam splitter 13 splits the laser emitted by the side-emitting laser 1102 into multiple randomly distributed lasers. When these lasers irradiate a plane, they form a pattern similar to... Figure 14As shown in the image, when multiple lasers illuminate the object to be photographed, the light spot pattern will deform or shift. After the first imaging module captures the light spot pattern on the surface of the object, it will obtain a depth image of the object's surface based on the deformation or shift of the light spot pattern, thus obtaining the depth information of the unevenness of the object's surface. The processing module 15 can then obtain a 3D image of the object based on the depth image and the 2D image.

[0083] In this embodiment of the invention, the reflective device 17 can be a reflective mirror or a triangular prism. A reflective film can be coated on the reflective surface of the triangular prism.

[0084] The imaging module 12 is a first imaging module, optionally an infrared camera. The first imaging module 12 obtains a depth image of the surface of the object to be photographed based on the light spot pattern of the laser reflected from the object.

[0085] In embodiments of the present invention, such as Figure 5 , Figure 6 , Figure 7 As shown, the imaging module 12 includes a second lamp lens 1201, a receiving lens 1202, and a photodetector array 1203; the photodetector array 1203 includes a plurality of photodetectors arranged in an array.

[0086] The second lamp lens 1201 is used to receive the laser reflected by the object to be photographed through another light-transmitting area, and after narrowing to its narrowest point at the aperture, it diffuses and projects the laser light onto the receiving lens;

[0087] The receiving lens 1202 is used to focus parallel lasers incident at the same angle onto an upper optical detector located on the focal plane of the receiving lens.

[0088] The photodetector is used to receive the laser-generated spot pattern and obtain a depth image of the surface of the object to be photographed based on the spot pattern.

[0089] In this embodiment of the invention, the photodetector may be a CMOS or CCD sensor.

[0090] Figure 12 This is a schematic diagram of a projection lens according to an embodiment of the present invention. Figure 13 This is another structural schematic diagram of the projection lens according to an embodiment of the present invention, as shown below. Figure 12 , Figure 13As shown, the projection lens includes a lens assembly 16 and a first lamp lens 19; the structured light projector is used to project structured light onto the projection lens, the structured light including multiple randomly distributed laser beams; the lens assembly 16 is used to converge the multiple laser beams and incident them onto the light-incident surface of the first lamp lens 19; the first lamp lens 19 is used to make the incident multiple laser beams exit in parallel or nearly parallel so that the laser beams pass through a light-transmitting area and illuminate the object to be photographed.

[0091] In this embodiment of the invention, "nearly parallel" specifically means that the angle between the two laser beams is less than a preset angle threshold, which can be set to 5°. "Multiple laser beams parallel" specifically means that multiple laser beams form multiple groups of laser beams, with the multiple laser beams within each group being parallel to each other.

[0092] In this embodiment of the invention, the lens assembly 16 includes a first lens 1601, a second lens 1602, and a lens barrel 1604. The first lens 1601 and the second lens 1602 are disposed on the light-incident side of the lens barrel; the first lamp mirror 19 is disposed on the light-outceasing side of the lens barrel. The first lens 1601 is used to converge the multiple laser beams and project them onto the second lens; the second lens 1602 is used to converge the multiple laser beams projected by the first lens again and project them onto the light-incident surface of the first lamp mirror. The lens barrel 1604 is used to assemble and fix the first lens 1601, the second lens 1602, and the first lamp mirror 19 into one unit. The light-incident side of the first lamp mirror 19 is provided with a concave light-incident opening; the bottom surface of the light-incident opening is the light-incident surface; the light-incident surface is a convex surface; the aperture of the projection lens is disposed on the convex surface. The light-incident surface is used to ensure that the incident multiple laser beams are emitted in parallel or nearly parallel to form an image at a specified distance at infinity or a distance.

[0093] In this embodiment of the invention, since the depth camera module is installed under a narrow light-emitting slit, the position of the aperture stop, i.e. the narrowest position of the beam, should be at the middle of the height of the narrow slit. Therefore, the lens can achieve the maximum field of view without blocking the light from the top and bottom sides.

[0094] When the projection lens is located on the backlight side of the display substrate 10, a first lamp lens 19 needs to be filled between the lens assembly 16 and the display substrate 10. Since the area available for light transmission is increasingly smaller, the aperture stop, the point where the light from the projection lens converges, needs to be placed at the position of the first lamp lens 19. Therefore, the diameter of the projection lens needs to be relatively large to ensure that light rays emitted at a certain angle converge at a designated position after traveling a certain distance. By making the lower surface of the first lamp lens 19 convex and placing the aperture stop of the projection lens on this convex surface, the first lamp lens 19 can handle a portion of the optical power, essentially acting as a convex lens. Simultaneously, by reducing the angle of light rays emitted from the lens below the first lamp lens 19, the effective aperture of the projection lens can be reduced, thereby reducing the overall system size.

[0095] In this embodiment of the invention, the upper surface of the first lamp lens 19 is in close contact with the lower surface of the display substrate 10, the protrusion structure on the upper part of the first lamp lens 19 is in close contact with the lower surface of the inner screen 40, and the lower edge of the first lamp lens 19 is in close contact with the projection lens barrel, which facilitates assembly and testing.

[0096] A spacer ring 1603 is provided between the first lens 1601 and the second lens 1602, and the spacer ring 1603 is used to fix the relative position between the first lens 2 and the second lens 4.

[0097] In this embodiment of the invention, a boss structure is provided on the light-emitting side of the first lamp lens; the end face of the boss structure is the light-emitting surface. The first lens 1601 and the second lens 1602 are convex lenses. The light-incident side of the first lamp lens 19 is fitted to the second lens 1602. The first lamp lens 19 is made of optical plastic material, which can both bear the function of optical power and provide dust protection between the projection lens and the display substrate 10.

[0098] In a modified embodiment of the present invention, a spacer 1605 is provided on the lens barrel 1604; the second lens 1602 is disposed on one side of the spacer 1605, and the lens barrel 1604 is disposed on the other side of the spacer 1605.

[0099] In this embodiment of the invention, the light rays incident on the first lens 1601 can be projected by any light projector, such as a structured light projector or a side-emitting laser, to project a pattern. The structured light emitted by the light projector can be multiple parallel telecentric beams, or it can be a beam with a principal ray at a certain angle.

[0100] In this embodiment of the invention, the beam splitter 13 may be a waveguide device, a nanophotonic chip, a diffractive optical element (DOE), or a coded structured photomask, etc., and the invention is not limited to these.

[0101] This invention also provides an electronic device, which includes the display device provided in any of the above embodiments. This electronic device can be a mobile phone, tablet computer, or digital camera, etc. The electronic device with a 3D camera module provided by this invention eliminates the need for a non-display area on the top of the display device to install the depth camera module, resulting in a more aesthetically pleasing appearance and facilitating a full-screen experience.

[0102] In this embodiment of the invention, light is focused onto the first lamp mirror by the first and second lenses of the lens assembly, and the aperture is positioned on the light-incident surface of the first lamp mirror. This allows the depth camera module with the projection lens to be installed in a narrow gap without obstructing the field of view (FOV), enabling the application of this invention on narrow-bezel screens (where the black matrix area is relatively narrow). It also allows the first lamp mirror to be flush against the phone's glass cover, providing dust protection. The display device and electronic device with a 3D camera module provided in this embodiment of the invention place the depth camera module on the backlight side of the black matrix area of ​​the display substrate, eliminating the need for a non-display area (notch) on the top of the display device to install the depth camera module, thus preserving the aesthetics and full-screen experience of the display device. In this embodiment of the invention, an infrared film layer is provided in the light-transmitting area of ​​the black matrix area. This infrared film layer allows infrared light to pass through without affecting the operation of the depth camera module, but visible light cannot pass through it, ensuring the integrity of the black matrix area and preserving the aesthetics of the display screen.

[0103] The various embodiments described in this specification are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0104] The various embodiments described in this specification are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0105] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A projection lens, characterized in that, Includes a first lens, a second lens, a lamp lens, and a lens barrel; The first lens and the second lens are disposed on the light-incident side of the lens barrel; the lamp lens is disposed on the light-outceasing side of the lens barrel; The first lens is used to converge multiple laser beams projected by the light source and project them onto the second lens; The second lens is used to refocus the multiple laser beams projected by the first lens and project them onto the light-incident surface of the lamp mirror; The lamp mirror is used to project the incident multiple laser beams. The light-incident side of the lamp mirror is provided with a concave light-incident opening; The bottom surface of the light inlet is the light-incident surface; the light-incident surface is a convex surface; the aperture of the second lens is disposed on the convex surface; The incident light surface is used to ensure that the incident multiple laser beams are emitted in parallel or nearly parallel. The light-emitting side of the lamp mirror is provided with a boss structure; The end face of the boss structure is the light-emitting surface.

2. The projection lens according to claim 1, characterized in that, A spacer ring is provided between the first lens and the second lens.

3. The projection lens according to claim 1, characterized in that, The first lens and the second lens are convex lenses.

4. The projection lens according to claim 1, characterized in that, The light-incident side of the lamp mirror is fitted to the second lens.

5. The projection lens according to claim 2, characterized in that, A partition frame is provided on the lens barrel; The second lens is disposed on one side of the partition frame, and the lens barrel is disposed on the other side of the partition frame.

6. The projection lens according to claim 2, characterized in that, The lamp mirror is made of optical plastic material.

7. A light projector, characterized in that, The projection lens includes any one of claims 1 to 6, and also includes a structured light projector; The structured light projector is used to project structured light onto the projection lens, the structured light comprising multiple randomly distributed laser beams; The projection lens is used to converge the multiple laser beams and incident them onto the light-incident surface of the lamp mirror, thereby causing the incident multiple laser beams to exit in parallel or nearly parallel through the lamp mirror.

8. A depth camera module, characterized in that, The light projector of claim 7 further includes an imaging module; The light projector is used to make the incident multiple laser beams exit in parallel or nearly parallel through the lamp lens so that the lasers illuminate the object to be photographed; The imaging module is used to receive the laser reflected by the object to be photographed through another light-transmitting area, and to obtain a depth image of the surface of the object to be photographed based on the light spot pattern of the laser reflected by the object to be photographed.

Images