Receiver module, transmitter module and TOF camera

Abstract

The present application designs the technical field of camera modules, and proposes a receiving end module, a transmitting end module and a TOF camera. The receiving end module includes a receiving end lens, which includes at least an incident light-transmitting layer, a first dimming layer group and a first light-distributing layer stacked from top to bottom; the first dimming layer group includes a first sub-wavelength structure layer; the first light-distributing layer includes a plurality of first micro-lens units arranged in an array. The transmitting end module includes a transmitting end lens, which includes an exit light-transmitting layer, a second dimming layer group and a second light-distributing layer stacked from top to bottom; the second dimming layer group includes a second sub-wavelength structure layer; the second light-distributing layer includes a plurality of second micro-lens units arranged in an array. The TOF camera includes the aforementioned receiving end module and transmitting end module. Compared with the prior art, the receiving end module and the transmitting end module of the present application are smaller in size and have fewer components, thereby reducing the overall size of the TOF camera.

Description

Technical Field

[0001] The utility model relates to the technical field of shooting lenses, and in particular to a receiving end module, a transmitting end module and a TOF camera. Background Art

[0002] TOF (Time offlight) cameras generally include a transmitter module and a receiver module. The transmitter module emits infrared light, which is reflected when it encounters the object being measured and received by the receiver module. By recording the time from the emission to the reception of the infrared light, the depth information of the illuminated object is calculated to complete the 3D modeling. By obtaining the distance of multiple points, the TOF camera's sensor system can effectively shape a 3D stereo model. This technology has been widely used in surveying and mapping, mobile phones, unmanned driving and other application fields.

[0003] See also Figure 1 At present, the receiving end module of the TOF camera generally includes a receiving end lens barrel 10, a receiving end circuit board 11 and an image chip 12; the image chip 12 is arranged on the top surface of the receiving end circuit board 11; the receiving end lens barrel 10 is fixedly connected to the top surface of the receiving end circuit board 11, and its bottom covers the image chip 12; the top of the receiving end lens barrel 10 is provided with a lens 13, which is a traditional lens, and the circumferential side wall of the lens 13 is threadedly connected with the inner wall of the top of the receiving end lens barrel 10, so that the lens 13 is installed on the receiving end lens barrel 10. However, the height of the lens 13 is relatively large, which will indirectly lead to a relatively large thickness of the overall receiving end module.

[0004] See also Figure 1 At present, the transmitting end module of the TOF camera generally includes a transmitting end circuit board 21, a transmitting end lens barrel 20 and an infrared light emitter 22. The infrared light emitter 22 is arranged on the top surface of the transmitting end circuit board 21; the transmitting end lens barrel 20 is fixedly connected to the top surface of the transmitting end circuit board 21, and its bottom covers the infrared light emitter 22. A diffractor 23 and a collimator 24 are arranged in the transmitting end lens barrel 20 from top to bottom. The collimator 24 is located above the infrared light emitter 22, and the light emitted by the infrared light emitter 22 passes through the collimator 24 and the diffractor 23 from bottom to top. However, since the diffractor 23 and the collimator 24 are arranged in the transmitting end lens barrel 20, this will cause the height of the transmitting end lens barrel 20 to be relatively large, which will indirectly cause the thickness of the transmitting end module to be relatively large.

[0005] In summary, since the thickness of the receiving module and the transmitting module is relatively large, it is not conducive to reducing the overall volume of the TOF camera.

[0006] In addition, the receiving module and the transmitting module need to be electrically connected to other parts in the TOF camera, such as the control unit, through flexible circuit boards and connectors respectively. Such a structure will greatly increase the number of parts inside the TOF camera, which is not conducive to reducing the size of the TOF camera.

[0007] Based on the above reasons, it is necessary to provide a method for reducing the size of a TOF camera. Utility Model Content

[0008] The utility model provides a receiving end module, a transmitting end module and a TOF camera, which have the advantage of small size.

[0009] The technical solution adopted by the utility model is as follows:

[0010] A receiving end module is applied to a TOF camera, comprising a receiving end lens, a first lens bracket, a chip sensor and a first circuit board. The receiving end lens is arranged above the first circuit board through the first lens bracket, and the chip sensor is arranged on the top surface of the first circuit board and corresponds to the position of the receiving end lens; the receiving end lens at least comprises an incident light-transmitting layer, a first dimming layer group and a first light-homogenizing layer which are stacked in sequence from top to bottom; the first dimming layer group comprises at least one first sub-wavelength structure layer for adjusting the light field of the incident light; the first light-homogenizing layer comprises a first light-homogenizing substrate, and a plurality of first micro-lens units are formed on the light emitting surface of the first light-homogenizing substrate; the plurality of first micro-lens units are arranged in an array.

[0011] In one embodiment, the first sub-wavelength structure layer includes a first dimming substrate, and a first sub-wavelength structure for adjusting the light field of the incident light is formed on the light incident surface and / or the light exit surface of the first dimming substrate.

[0012] In one embodiment, the first subwavelength structure includes a plurality of first light-transmitting protrusions; the plurality of first light-transmitting protrusions are protruded on the light incident surface and / or the light exit surface of the first dimming substrate; the first light-transmitting protrusions are cylindrical protrusions, or elliptical cylindrical protrusions, or frustum-shaped protrusions, prismatic protrusions, or hemispherical protrusions.

[0013] In one embodiment, each of the plurality of first microlens units includes a plurality of first lenses, and the plurality of first lenses are formed on the light emitting surface of the first light-homogenizing substrate at intervals from each other.

[0014] In one embodiment, a light emitting surface of the first light-homogenizing substrate is provided with a filter layer; the filter layer covers all the first lenses.

[0015] In one embodiment, a plurality of first sub-wavelength structure layers are configured, and all first sub-wavelength structure layers are stacked in sequence from top to bottom; and a light-transmitting spacer is disposed between adjacent first sub-wavelength structure layers.

[0016] A transmitting end module, which is used to emit light for reception by a receiving end module as claimed in claim 1, characterized in that the transmitting end module includes a transmitting end lens, a second lens holder, a light emitter and a second circuit board; the transmitting end lens is arranged above the second circuit board through the second lens holder, and the light emitter is arranged on the top surface of the second circuit board and corresponds to the position of the transmitting end lens; the transmitting end lens at least includes an output light-transmitting layer, a second dimming layer group and a second light-homogenizing layer stacked in sequence from top to bottom; the second dimming layer group includes at least one second sub-wavelength structure layer for adjusting the light field of the incident light; the second light-homogenizing layer includes a second light-homogenizing substrate, and a plurality of second micro-lens units are formed on the light incident surface of the second light-homogenizing substrate; the plurality of second micro-lens units are arranged in an array.

[0017] In one embodiment, the second subwavelength structure layer includes a second dimming substrate, and a second subwavelength structure for adjusting the light field of the incident light is formed on the light incident surface and / or the light exit surface of the second dimming substrate; the second subwavelength structure includes a plurality of second light-transmitting protrusions; the plurality of second light-transmitting protrusions are protruding on the light incident surface and / or the light exit surface of the second dimming substrate; the second light-transmitting protrusions are cylindrical protrusions, or elliptical cylindrical protrusions, or frustum-shaped protrusions, prismatic protrusions, or hemispherical protrusions.

[0018] In one embodiment, each of the plurality of second microlens units includes a plurality of second lenses, and the plurality of second lenses are formed on the light incident surface of the second light-homogenizing substrate at intervals.

[0019] A TOF camera comprises a bracket cover, the above-mentioned receiving end module and the above-mentioned transmitting end module; a first circuit board and a second circuit board are integrally formed to form a circuit substrate; the circuit substrate is provided with a first conductive welding pad and a second conductive welding pad for electrically connecting to an external component; the bracket cover is covered on the top surface of the circuit substrate, and the bracket cover is provided with two windows; a first lens bracket and a second lens bracket are fixedly connected to the bracket cover, and are located above the two windows one by one.

[0020] The beneficial effects of the utility model are:

[0021] The receiving end lens of the present application includes an incident light-transmitting layer, a first dimming layer group and a first light-homogenizing layer, wherein the first dimming layer group uses a first sub-wavelength structure layer to adjust the incident light field, and the first light-homogenizing layer uses a plurality of second micro-lens units arranged in an array to adjust the range of light emission, so that the light can be irradiated on the chip sensor more evenly, thereby improving the imaging quality. Compared with the prior art, the receiving end lens of the present application can reduce the thickness of the entire receiving end lens while ensuring the imaging quality by virtue of the smaller thickness of the first dimming layer group and the first light-homogenizing layer, and finally reduce the thickness of the entire receiving end module and reduce the volume of the receiving end module.

[0022] In addition, the transmitting end lens of the present application includes an output light-transmitting layer, a second dimming layer group, and a second light-homogenizing layer. The second light-homogenizing layer of the present application uses a plurality of second microlens units to adjust the emission range of light, so that the light emitted by the light emitter can enter the second dimming layer group more evenly. After the second dimming layer group uses a second sub-wavelength structure layer to adjust the light field, the light is emitted from the output light-transmitting layer in a more dispersed manner, so that the light covers a wider range. Compared with the prior art, the transmitting end lens of the present application does not need to set up an additional independent collimator to adjust the emission range of light, thereby reducing the number of parts and thus reducing the thickness of the transmitting end lens. In addition, the thickness of the entire transmitting end lens can be further reduced by virtue of the smaller thickness of the second dimming layer group and the second light-homogenizing layer. Ultimately, the thickness of the entire receiving end module is reduced and the volume of the receiving end module is reduced.

[0023] In this way, the thickness and structural volume of the receiving end lens and the transmitting end lens of the present application are relatively small, which is beneficial to reducing the overall structural volume of the TOF camera.

[0024] In addition, the first circuit board and the second circuit board of the present application are integrally formed to form a circuit substrate, and the circuit substrate is provided with a first conductive welding pad and a second conductive welding pad for electrically connecting to external components. When the circuit substrate is installed inside the device, its first conductive welding pad and the second conductive welding pad are directly in contact and welded with the conductive ends of other parts or other circuit boards, thereby eliminating the conductive parts that act as conductive media between the two, such as flexible circuit boards and connectors, and ultimately reducing the number of parts of the entire TOF camera, thereby reducing its overall volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the utility model and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the utility model, but should not constitute a limitation of the utility model.

[0026] Figure 1 It is a structural schematic diagram of the prior art of the embodiment of the utility model;

[0027] Figure 2 A schematic diagram of the combined structure of a TOF camera according to an embodiment of the utility model;

[0028] Figure 3 This is a schematic cross-sectional structural diagram of a TOF camera according to an embodiment of the present utility model;

[0029] Figure 4 This is a schematic diagram of the structure of a receiving end lens of an embodiment of the utility model;

[0030] Figure 5 This is a schematic diagram of the bottom structure of the first light-homogenizing layer of an embodiment of the utility model;

[0031] Figure 6 It is a schematic structural diagram of the second light-homogenizing layer of an embodiment of the utility model.

[0032] Notes on the attached drawings:

[0033] 10. Receiver lens barrel; 11. Receiver circuit board; 12. Image chip; 13. Lens;

[0034] 20. Transmitter lens barrel; 21. Transmitter circuit board; 22. Infrared light transmitter; 23. Diffractor; 24. Collimator;

[0035] 30, receiving end lens; 31, first lens bracket; 311, first sink; 312, first light through hole; 32, chip sensor; 33, incident light-transmitting layer; 341, first sub-wavelength structure layer; 3411, first light-transmitting protrusion; 342, light-transmitting spacer; 35, first light-homogenizing layer; 351, first microlens unit; 36, filter layer;

[0036] 40, emitting end lens; 41, second lens bracket; 411, second sink; 412, second light through hole; 42, light emitter; 43, exit light-transmitting layer; 441, second sub-wavelength structure layer; 442, second light-transmitting protrusion; 45, second light-homogenizing layer; 451, second microlens unit;

[0037] 50. Bracket cover;

[0038] 60. Circuit substrate; 61. First circuit board; 62. Second circuit board. DETAILED DESCRIPTION

[0039] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0040] This embodiment discloses a TOF camera, which can be applied to mobile phones, drones, sweepers, robots and other electronic devices that require a shooting function.

[0041] See also Figure 2 and Figure 3 The TOF camera of this embodiment includes a receiving end module, a transmitting end module, a bracket cover 50 and a circuit substrate 60.

[0042] The transmitting end module is used to transmit light, and the receiving end module has the function of receiving light emitted by the transmitting end module and reflected back.

[0043] The support cover 50 is covered on the top surface of the circuit substrate 60 . The support cover 50 is provided with two windows, one for allowing the light received by the receiving end module to pass through and the other for allowing the light emitted by the transmitting end module to pass through.

[0044] The receiving end module of this embodiment includes a receiving end lens 30 , a first lens bracket 31 , a chip sensor 32 and a first circuit board 61 . The transmitting end module includes a transmitting end lens 40 , a second lens bracket 41 , a light emitter 42 and a second circuit board 62 .

[0045] Among them, the first circuit board 61 and the second circuit board 62 are integrally formed to form a circuit substrate 60. Such a structural method can make the internal structure of the TOF camera more compact, which is beneficial to reducing its volume. At the same time, it can also reduce the processing steps in its manufacturing process to reduce manufacturing costs.

[0046] In this embodiment, the bottom surface of the circuit substrate 60 is provided with a first conductive welding pad (not shown in the figure) and a second conductive welding pad (not shown in the figure) for electrically connecting to external components. When the TOF camera is assembled on an electronic device, the first conductive welding pad and the second conductive welding pad respectively abut or fix the conductive connector of the electronic device, so that the electronic device can be electrically connected to the circuit substrate 60 to realize the transmission of power and signals between the electronic device and the receiving end module and the transmitting end module. Compared with the prior art, this embodiment does not need to additionally set up a flexible circuit board and a connector to electrically connect the circuit substrate 60 and the external components, which can reduce the parts of the TOF camera, thereby reducing the volume of the TOF camera and reducing its manufacturing cost. In other embodiments, the installation position of the first conductive welding pad and the second conductive welding pad can also be changed according to the assembly requirements.

[0047] In this embodiment, the first conductive welding pad and the second conductive welding pad can be composed of multiple solder points. When assembling the circuit substrate 60, the molten solder material is first spot-welded to the first conductive welding pad and the second conductive welding pad of the circuit substrate 60, and then the first conductive welding pad and the second conductive welding pad of the circuit substrate 60 are abutted against each conductive joint of the electronic device. After the solder material solidifies, the solder material can fix the first conductive welding pad and the second conductive welding pad to the conductive joint of the electronic device and electrically connect them to the conductive joint.

[0048] In this embodiment, the receiving end lens 30 is arranged above the first circuit board 61 through the first lens bracket 31. Specifically, the bottom surface of the first lens bracket 31 is glued to the top surface of the bracket cover 50 to achieve the fixed connection between the two; in actual application scenarios, the installation position of the first lens bracket 31 on the bracket cover 50 can be adjusted according to actual needs, so that the receiving end lens 30 is fixed to the top surface of the bracket cover 50 through the first lens bracket 31, so that the receiving end lens 30 can be suspended above the first circuit board 61.

[0049] Furthermore, a recessed first platform 311 is provided on the top surface of the first lens holder 31, and a first light through hole 312 penetrating the bottom surface of the first lens holder 31 is provided at the bottom of the first platform 311, and the position of the first light through hole 312 corresponds to the position of one of the windows on the holder cover 50; the receiving end lens 30 is embedded in the first platform 311, and the top surface of the receiving end lens 30 is flush with the outer port of the first platform 311, so that the surface flatness of the receiving end module can be improved.

[0050] The chip sensor 32 is arranged on the top surface of the first circuit board 61 to receive the light entering from the receiving end lens 30. Specifically, the chip sensor 32, the corresponding window of the bracket cover 50, the first light through hole 312 and the receiving end lens 30 are located on the same straight line, so that the external light can enter the receiving end module from top to bottom, and finally be received by the chip sensor 32, and the chip sensor 32 generates a related light signal.

[0051] In this embodiment, the transmitting end lens 40 is arranged above the second circuit board 62 through the second lens bracket 41. Specifically, the bottom surface of the second lens bracket 41 is glued to the top surface of the bracket cover 50 to achieve the fixed connection between the two; in actual application scenarios, the installation position of the second lens bracket 41 on the bracket cover 50 can be adjusted according to actual needs. Further, a recessed second sink 411 is provided on the top surface of the second lens bracket 41, and a second light through hole 412 that passes through the bottom surface of the second lens bracket 41 is provided at the bottom of the second sink 411, and the position of the second light through hole 412 corresponds to the position of another window on the bracket cover 50; the transmitting end lens 40 is embedded in the second sink 411, and the top surface of the transmitting end lens 40 is flush with the outer port of the second sink 411, so that the surface flatness of the transmitting end module can be improved.

[0052] The light emitter 42 is disposed on the top surface of the first circuit board 61. The light emitter 42 may be an infrared emitter for emitting infrared light. Of course, the light emitter 42 may also be other light emitting components that can emit specific light. The light emitter 42, the corresponding window of the bracket cover 50, the second light through hole 412 and the transmitting end lens 40 are located on the same straight line, so that the light emitted by the light emitter 42 can pass through the transmitting end lens 40 from bottom to top and finally diffuse outside the transmitting end module.

[0053] Next, the structure of the receiving end lens 30 of this embodiment is further described.

[0054] Please combine Figure 3 and Figure 4 In this embodiment, the receiving end lens 30 at least includes an incident light-transmitting layer 33, a first dimming layer group, and a first light-distributing layer 35, which are stacked in sequence from top to bottom. The incident light-transmitting layer 33, the first dimming layer group, and the first light-distributing layer 35 can be connected as a whole by gluing to form the receiving end lens 30.

[0055] In this embodiment, the incident light-transmitting layer 33 is used to allow light to pass through and to protect the first dimming layer group. In addition, it also has a certain dimming effect, such as uniform light, focusing light or dispersing light. The incident light-transmitting layer 33 can be a plane lens, or a concave lens, or a convex lens, or a lens with a convex top surface and a flat bottom surface, or a lens with a concave top surface and a flat bottom surface, or other lenses of applicable shapes. When the incident light-transmitting layer 33 is a plane mirror, it only plays a protective role and a certain light-homogenizing role. When the incident light-transmitting layer 33 is a concave lens or a convex lens, it can play a role in adjusting the range of light, such as focusing or dispersing light. The incident light-transmitting layer 33 can be a light-transmitting layer made of glass, a light-transmitting layer made of resin, etc., as long as it can transmit light and has a certain hardness to play a protective role.

[0056] In this embodiment, the first dimming layer group includes three first sub-wavelength structure layers 341 stacked from top to bottom for adjusting the light field of the incident light and two transparent spacers 342. A layer of transparent spacer 342 is provided between adjacent first sub-wavelength structure layers 341, and the transparent spacer 342 is used to isolate two adjacent first sub-wavelength structure layers 341 to prevent the surfaces of the two first sub-wavelength structure layers 341 from being squeezed against each other and damaging their own surface structural features. The transparent spacer 342 is a transparent flat lens, and its material can be a transparent material such as glass, resin, etc.

[0057] Of course, in other embodiments, the number of first sub-wavelength structural layers 341 may be one layer, two layers, or more than three layers, and the number of light-transmitting interlayers 342 may be changed according to the number of first sub-wavelength structural layers 341. For example, when the first sub-wavelength structural layer 341 is one layer, the light-transmitting interlayer 342 may not be provided. When more than two first sub-wavelength structural layers 341 are provided, it is necessary to ensure that a light-transmitting interlayer 342 is provided between every two adjacent first sub-wavelength structural layers 341.

[0058] In the present embodiment, the first sub-wavelength structure layer 341 includes a first dimming substrate, and a first sub-wavelength structure for adjusting the light field of the incident light is formed on the light incident surface and / or light exit surface of the first dimming substrate. Specifically, since the light passes through the first dimming substrate from top to bottom, the top surface of the first dimming substrate is the light incident surface, and the bottom surface is the light exit surface. The first dimming substrate can be a light-transmitting glass layer or resin layer, etc. The top surface or bottom surface of the first dimming substrate is provided with a first sub-wavelength structure, or the top surface and bottom surface of the first dimming substrate are provided with a first sub-wavelength structure at the same time. The first sub-wavelength structure can adjust the phase, amplitude, polarization and other light fields of the incident light, so as to control the phase delay, achieve the purpose of controlling the optical path difference, and facilitate obtaining a good imaging effect.

[0059] In this embodiment, the first sub-wavelength structure includes a plurality of first light-transmitting protrusions 3411; the plurality of first light-transmitting protrusions 3411 are convexly arranged on the light incident surface and / or light emitting surface of the first dimming substrate. Specifically, nano-material processing technology can be used to perform nano-level processing on the surface of the first dimming substrate, so that a plurality of nano-level first light-transmitting protrusions 3411 can be formed on the top surface and / or bottom surface of the first dimming substrate, and the structural size (particle size or height) of the first light-transmitting protrusions 3411 is smaller than the wavelength of the light wave, so that the plurality of first light-transmitting protrusions form a first sub-wavelength structure, and the first sub-wavelength structure obtains peculiar properties such as negative refractive index and zero refractive index.

[0060] The first light-transmitting protrusions 3411 may be cylindrical protrusions, elliptical protrusions, frustum-shaped protrusions, prism-shaped protrusions, or hemispherical protrusions. The structural dimensions (particle diameter or height) and shapes of the first light-transmitting protrusions 3411 may be the same or different.

[0061] Please combine Figure 4 and Figure 5 In this embodiment, the first light-homogenizing layer 35 includes a first light-homogenizing substrate, which may be a light-transmitting resin layer, a light-transmitting glass layer, or the like. A plurality of first microlens units 351 are formed on the light-emitting surface of the first light-homogenizing substrate. The plurality of first microlens units 351 are arranged in an array, and each first microlens unit 351 evenly distributes the incident light into surface light, so that each part of the chip sensor 32 can receive light more evenly. Specifically, the first light-homogenizing substrate may be a circular plate with a diameter of 12 inches, which may include 5,000 square or circular first microlens units 351. The side length or diameter of each first microlens unit 351 is 1 mm.

[0062] In the present embodiment, each of the plurality of first microlens units 351 includes a plurality of first lenses (not shown in the figure), and the plurality of first lenses are formed at intervals on the light emitting surface of the first light-evening substrate (i.e., the bottom surface of the first light-evening substrate), and the first lens may be hemispherical. Specifically, nano-machining technology may be used to process the emitting surface of the first light-evening substrate so that the light emitting surface of the first light-evening substrate forms the aforementioned first lens, and the particle size of the first lens is smaller than the wavelength of the light. Each first lens may adjust the light individually, and each first microlens unit 351 adjusts the light in a small range. When all the first microlens units 351 adjust the light at the same time, the light may be finally homogenized into a surface light source, and the surface light source may be more evenly received by the chip sensor 32, thereby improving the imaging effect.

[0063] In this embodiment, the light emitting surface of the first light-homogenizing substrate is further provided with a filter layer 36. The filter layer 36 covers all the first lenses. The filter layer 36 is used to filter the light of unnecessary wavelengths. The filter layer 36 can be a filter film coated on the light emitting surface of the first light-homogenizing substrate.

[0064] Compared with the prior art, the receiving end lens 30 of this embodiment uses the first sub-wavelength structure layer 341 to adjust the incident light field, and the first light-homogenizing layer 35 adjusts the range of light emission through multiple second micro-lens units 451 arranged in an array, so that the light can be irradiated on the chip sensor 32 more evenly, thereby improving the imaging quality. Compared with the prior art, the receiving end lens 30 of this embodiment can reduce the thickness of the entire receiving end lens 30 while ensuring the imaging quality by virtue of the smaller thickness of the first dimming layer group and the first light-homogenizing layer 35, thereby reducing the thickness of the entire receiving end module and reducing the volume of the receiving end module, and finally reducing the volume of the TOF camera.

[0065] Next, the structure of the transmitting end lens 40 of this embodiment is further described.

[0066] Please combine Figure 3 and Figure 6 In this embodiment, the transmitting end lens 40 at least includes an output light-transmitting layer 43, a second light-adjusting layer group, and a second light-distributing layer 45, which are stacked in sequence from top to bottom. The output light-transmitting layer 43, the second light-adjusting layer group, and the second light-distributing layer 45 can be connected as a whole by gluing to form a transmitting end lens.

[0067] The material of the outgoing light-transmitting layer 43 may be the same as the material of the incident light-transmitting layer 33 of the receiving end lens 30. The outgoing light-transmitting layer 43 may be a flat lens, which is used to allow light to pass through and to protect the second dimming layer group.

[0068] The second dimming layer group includes at least one second sub-wavelength structure layer 441 , which is used to adjust the light field of the incident light, that is, to adjust the light field of the light emitted by the light emitter 42 , such as adjusting the phase, amplitude, polarization, etc. of the light.

[0069] The second sub-wavelength structure layer 441 includes a second dimming substrate, and a second sub-wavelength structure for adjusting the light field of the incident light is formed on the light incident surface and / or light exit surface of the second dimming substrate. Specifically, since the light passes through the second dimming substrate from bottom to top, the bottom surface of the second dimming substrate is the light incident surface, and the top surface is the light exit surface. The second dimming substrate can be a transparent glass layer or resin layer, etc. The top surface or bottom surface of the second dimming substrate is provided with a second sub-wavelength structure, or the top surface and bottom surface of the second optical substrate are provided with a second sub-wavelength structure at the same time. The second sub-wavelength structure can adjust the light field such as the phase, amplitude, and polarization of the incident light, so as to control the phase delay, achieve the purpose of controlling the optical path difference, and facilitate obtaining a good imaging effect. The second sub-wavelength structure includes a plurality of second light-transmitting protrusions 442, and the shape and structure of the second light-transmitting protrusions 442 are equivalent to the shape and structure of the first light-transmitting protrusions 3411, so the shape and structure of the second light-transmitting protrusions 442 are not further elaborated here.

[0070] In this embodiment, the second light-homogenizing layer 45 includes a second light-homogenizing substrate, which may be a light-transmitting glass layer, a light-transmitting resin layer, etc. A plurality of second microlens units 451 are formed on the light incident surface of the second light-homogenizing substrate. The plurality of second microlens units 451 are arranged in an array, and the incident light is evenly dispersed into surface light by each second microlens unit 451, so that the surface light can pass through the second dimming layer group more evenly, so that the light field of the light can be adjusted by the second dimming layer group.

[0071] Specifically, the second light-homogenizing substrate may be a circular plate with a diameter of 12 inches, and the circular plate may include 5000 square or circular second microlens units 451. The side length or diameter of each second microlens unit 451 is 1 mm.

[0072] In this embodiment, the second microlens unit 451 is composed of a plurality of second lenses (not shown in the figure). Specifically, the structure and shape of the second lens can be equivalent to the structure and shape of the first lens, and both are hemispherical. Each second lens can adjust the light individually, and each second microlens unit 451 can adjust the light in a small range. When all the second microlens units 451 adjust the light at the same time, the light can be homogenized into a surface light source, and the surface light source can pass through the second dimming layer group more evenly.

[0073] Compared with the prior art, the second light-homogenizing layer 45 of this embodiment uses a plurality of second microlens units 451 to adjust the emission range of light, so that the light emitted by the light emitter 42 can enter the second dimming layer group more evenly. After the second dimming layer group uses the second sub-wavelength structure layer 441 to adjust the light field, the light is emitted from the exit light-transmitting layer 43 in a more dispersed manner, so that the light covers a wider range. Compared with the prior art, the transmitting end lens 40 of this embodiment does not need to set up an additional independent collimator to adjust the emission range of light, so the number of parts can be reduced, thereby reducing the thickness of the transmitting end lens 40. In addition, the thickness of the entire transmitting end lens 40 can be further reduced by relying on the characteristics of the second dimming layer group and the second light-homogenizing layer 45, thereby reducing the thickness of the entire receiving end module and reducing the volume of the receiving end module, and finally reducing the volume of the TOF camera.

[0074] As long as it does not violate the creative idea of ​​the utility model, any combination of various different embodiments of the utility model should be regarded as the content disclosed by the utility model; within the technical concept of the utility model, any simple modification of the technical solution and any combination of different embodiments that do not violate the creative idea of ​​the utility model should be within the protection scope of the utility model.

Claims

1. A receiving end module, applied to a TOF camera, comprising a receiving end lens (30), a first lens bracket (31), a chip sensor (32) and a first circuit board (61), wherein the receiving end lens (30) is arranged above the first circuit board (61) through the first lens bracket (31), and the chip sensor (32) is arranged on the top surface of the first circuit board (61) and corresponds to the position of the receiving end lens (30); characterized in that: The receiving end lens (30) comprises at least an incident light-transmitting layer (33), a first light-adjusting layer group and a first light-homogenizing layer (35) which are stacked in sequence from top to bottom; the first light-adjusting layer group comprises at least one first sub-wavelength structure layer (341) for adjusting the light field of the incident light; the first light-homogenizing layer (35) comprises a first light-homogenizing substrate, a plurality of first micro-lens units (351) being formed on a light emitting surface of the first light-homogenizing substrate; the plurality of first micro-lens units (351) are arranged in an array.

2. The receiving end module according to claim 1, characterized in that: The first sub-wavelength structure layer (341) comprises a first dimming substrate, and a first sub-wavelength structure for adjusting the light field of the incident light is formed on the light incident surface and / or the light exit surface of the first dimming substrate.

3. The receiving end module according to claim 2, characterized in that: The first sub-wavelength structure comprises a plurality of first light-transmitting protrusions (3411); the plurality of first light-transmitting protrusions (3411) are protrudingly arranged on the light incident surface and / or the light exit surface of the first dimming substrate; the first light-transmitting protrusions (3411) are cylindrical protrusions, or elliptical protrusions, or frustum-shaped protrusions, prismatic protrusions, or hemispherical protrusions.

4. The receiving end module according to claim 1, characterized in that: Each of the plurality of first microlens units (351) comprises a plurality of first lenses, and the plurality of first lenses are formed on a light emitting surface of the first light-uniform substrate at intervals from each other.

5. The receiving end module according to claim 4, characterized in that: A light emitting surface of the first light-homogenizing substrate is provided with a filter layer (36); the filter layer (36) covers all of the first lenses.

6. The receiving end module according to claim 1, characterized in that: The first sub-wavelength structural layers (341) are arranged in a plurality, and all the first sub-wavelength structural layers (341) are stacked in sequence from top to bottom; and a light-transmitting spacer (342) is provided between adjacent first sub-wavelength structural layers (341).

7. A transmitting end module, used for emitting light for receiving by the receiving end module as claimed in claim 1, characterized in that: The transmitting end module comprises a transmitting end lens (40), a second lens bracket (41), a light emitter (42) and a second circuit board (62); the transmitting end lens (40) is arranged above the second circuit board (62) through the second lens bracket (41), and the light emitter (42) is arranged on the top surface of the second circuit board (62) and corresponds to the position of the transmitting end lens (40); the characteristics are: The emission end lens (40) comprises at least an output light-transmitting layer (43), a second light-adjusting layer group and a second light-homogenizing layer (45) which are stacked in sequence from top to bottom; the second light-adjusting layer group comprises at least one second sub-wavelength structure layer (441) for adjusting the light field of incident light; the second light-homogenizing layer (45) comprises a second light-homogenizing substrate, and a plurality of second micro-lens units (451) are formed on the light incident surface of the second light-homogenizing substrate; the plurality of second micro-lens units (451) are arranged in an array.

8. The transmitting end module according to claim 7, characterized in that: The second sub-wavelength structure layer (441) comprises a second dimming substrate, and a second sub-wavelength structure for adjusting the light field of the incident light is formed on the light incident surface and / or the light exit surface of the second dimming substrate; the second sub-wavelength structure comprises a plurality of second light-transmitting protrusions (442); the plurality of second light-transmitting protrusions (442) are protrudingly arranged on the light incident surface and / or the light exit surface of the second dimming substrate; the second light-transmitting protrusions (442) are cylindrical protrusions, or elliptical cylindrical protrusions, or frustum-shaped protrusions, prismatic protrusions, or hemispherical protrusions.

9. The transmitting end module according to claim 7, characterized in that: Each of the plurality of second microlens units (451) comprises a plurality of second lenses, and the plurality of second lenses are formed at intervals from one another on the light incident surface of the second light-uniform substrate.

10. A TOF camera, characterized in that: It comprises a bracket cover plate (50), a receiving end module as claimed in claim 1 and a transmitting end module as claimed in claim 7; the first circuit board (61) and the second circuit board (62) are integrally formed to constitute a circuit substrate (60); the circuit substrate (60) is provided with a first conductive welding pad and a second conductive welding pad for electrically connecting to an external component; the bracket cover plate (50) is covered on the top surface of the circuit substrate (60), and the bracket cover plate (50) is provided with two windows; the first lens bracket (31) and the second lens bracket (41) are fixedly connected to the bracket cover plate (50), and are located above the two windows one by one.

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