WO2020073764A1

WO2020073764A1 - Projection module, imaging device, and electronic device

Info

Publication number: WO2020073764A1
Application number: PCT/CN2019/104976
Authority: WO
Inventors: 李宗政; 肖德塘; 陈冠宏; 周祥禾; 林君翰
Original assignee: 南昌欧菲生物识别技术有限公司
Priority date: 2018-10-11
Filing date: 2019-09-09
Publication date: 2020-04-16

Abstract

A projection module (10), an imaging device (100) and an electronic device (1000). The projection module (10) comprises a light source (12), a diffuser (14), and a photomask (16), the light source (12) being used to emit light rays. The diffuser (14) is used to diffuse the light rays emitted by the light source (12) into uniform light rays. The photomask (16) is used to project the uniform light rays emitted by the diffuser (14) as structured light rays, the diffuser (14) being positioned between the light source (12) and the photomask (16).

Description

Projection module, imaging device and electronic device

Priority information

This application requests the priority and rights and interests of the patent applications filed on October 11, 2018 and filed with the State Intellectual Property Office of China with application numbers 201811187723.1 and 201821651711.5, and the entire contents of which are incorporated herein by reference.

Technical field

The invention relates to the field of image acquisition technology, in particular to a projection module, an imaging device and an electronic device.

Background technique

In the related art, an imaging device for collecting three-dimensional contour information of an object is receiving more and more attention. The imaging device can project specific light information to the object through structured light technology, and the image sensor receives the light reflected by the object and calculates according to the change of the light information. The three-dimensional contour information of the object. Among them, in coded structured light technology, a vertical cavity surface emitting laser (Vertical Cavity Surface Emitting Laser, VCSEL) array is generally used as a light source, and the light rays form a structured light through a mask, however, the vertical cavity surface emitting laser emits The light is concentrated and the divergence angle is small. A certain distance is required between the light source and the reticle to diffuse the light to form an overlap, so that the light passing through the reticle is more uniform, which is not conducive to the miniaturization of the imaging device. In addition, due to the distribution of the overlapping area, the light still has an uneven phenomenon in the overlapping area, which affects the quality of the projected structured light pattern.

Summary of the invention

Embodiments of the present invention provide a projection module, an imaging device, and an electronic device.

A projection module according to an embodiment of the present invention includes a light source, a diffuser, and a light cover. The light source is used to emit light; the diffuser is used to diffuse the light emitted by the light source to form uniform light; The uniform light emitted from the diffuser is projected to form structured light, and the diffuser is located between the light source and the reticle.

In the projection module according to the embodiment of the present invention, a diffuser is provided between the light source and the light cover to diffuse the light emitted by the light source, and the distance between the light source and the light cover can be relatively close, thereby facilitating the miniaturization design of the projection module, , Diffusing through the diffuser can form uniform light, making the structured light formed by the photomask better.

In some embodiments, the diffuser and the light source are spaced apart, and the diffuser and the reticle are spaced apart. In this way, the diffuser can be arranged as an independent element between the light source and the reticle, which can diffuse the light emitted by the light source and make the light distribution in the projection module uniform.

In some embodiments, the diffuser is disposed on the reticle. In this way, the diffuser and the reticle can be designed as one element. Similarly, the uniform light diffused by the diffuser can be projected through the reticle to form structured light.

In some embodiments, the diffuser may be made by adding a scattering material to the material layer, or by making scattering characteristics on the surface layer of the material layer, or by designing a diffractive microstructure on the surface of the material layer, or It is made by designing micro lens array refractive microstructure on the surface of the material layer. Diffusers can choose different designs according to different uses and optical requirements, which can meet more scene needs.

In some embodiments, the photomask includes a light-transmitting area and a light-shielding area, the light-transmitting area forming a structured pattern. In this way, since the light-transmitting region forms a structured pattern, the light projected through the photomask can form structured light corresponding to the structured pattern, that is, the photomask can project the light to form structured light.

In some embodiments, the projection module includes a projection lens on the light-emitting side of the reticle, and the projection lens is used to project the structured light. In this way, the projection module can improve the effect of structured light projection through the projection lens and achieve corresponding imaging quality.

In some embodiments, the light source includes a vertical cavity surface emitting laser array, and the vertical cavity surface emitting laser array includes a plurality of vertical cavity surface emitting lasers distributed in an array. In this way, the use of a vertical cavity surface emitting laser array as a light source can meet the requirement of a small volume of the light source, and the array distribution formed by multiple vertical cavity surface emitting lasers can ensure the continuity of structured light projection.

An imaging device according to an embodiment of the present invention includes a receiving module and a projection module. The projection module is used to project structured light. The receiving module is used to receive light reflected by the structured light through an object. The projection The module includes a light source, a diffuser, and a light mask, the light source is used to emit light; the diffuser is used to diffuse the light emitted by the light source to form uniform light; and the light mask is used to uniformly emit the diffuser Light projection forms structured light, and the diffuser is located between the light source and the reticle.

In the imaging device according to the embodiment of the present invention, a diffuser is provided between the light source of the projection module and the reticle. The diffuser can diffuse the light emitted by the light source, and the distance between the light source and the reticle can be relatively close, thereby facilitating the projection mode The miniaturized design of the group and imaging device, meanwhile, diffused through the diffuser can form uniform light, making the structured light formed by the photomask better.

In some embodiments, the diffuser may be made by adding a scattering material to the material layer, or by making scattering characteristics on the surface layer of the material layer, or by designing a diffractive microstructure on the surface of the material layer, or It is made by designing micro lens array refractive microstructure on the surface of the material layer. The diffuser 14 can choose different designs according to different uses and optical requirements, which can meet more scene requirements.

In some embodiments, in some embodiments, the receiving module and the projection module are arranged side by side. In this way, it is beneficial for the projection module to project structured light and the light reflected by the object is received by the receiving module.

In some embodiments, the receiving module includes an imaging lens and an image sensor, the image sensor is located on the image side of the imaging lens, and the imaging lens is used to concentrate incident light to the image sensor. In this way, the image sensor can collect the light reflected by the object, and the imaging lens can condense the light to the image sensor, which is helpful for the receiving module to receive the structured light reflected by the projection module after being projected onto the object.

In some embodiments, the receiving module includes a filter, and the filter is located between the imaging lens and the image sensor. In this way, the filter can filter other light than the light projected by the projection module to avoid interference of other light, so that the image information formed by the image sensor collecting light is more accurate.

An electronic device according to an embodiment of the present invention includes the imaging device described in any of the above embodiments.

In the electronic device according to the embodiment of the present invention, the projection module of the imaging device is provided with a diffuser between the light source and the reticle to diffuse the light emitted by the light source. The miniaturized design of the imaging device and the electronic device, at the same time, diffused through the diffuser can form uniform light, making the structured light formed by the photomask better.

Additional aspects and advantages of the present invention will be partially given in the following description, and some will become apparent from the following description, or be learned through the practice of the present invention.

BRIEF DESCRIPTION

The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

FIG. 1 is a schematic structural diagram of a projection module according to an embodiment of the present invention.

2 is another schematic structural diagram of a projection module according to an embodiment of the present invention.

3 is a schematic diagram of light distribution of uniform light projected by a diffuser according to an embodiment of the present invention.

4 is a schematic view of the structure of a photomask according to an embodiment of the present invention.

5 is a schematic diagram of structured light projected by a projection module according to an embodiment of the present invention.

6 is a schematic diagram of the structure of an imaging device according to an embodiment of the present invention.

7 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

Symbol description of main components:

Projection module 10, light source 12, vertical cavity surface emitting laser 122, diffuser 14, reticle 16, light-transmitting area 162, light-shielding area 164, projection lens 18;

Imaging device 100, receiving module 20, imaging lens 22, image sensor 24, filter 26;

Electronic device 1000.

detailed description

The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the drawings, in which the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary, and are only used to explain the present invention, and cannot be construed as limiting the present invention.

In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise specifically limited.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the invention. In addition, the present invention may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

Please refer to FIGS. 1 and 2 together. The projection module 10 according to the embodiment of the present invention includes a light source 12, a diffuser 14 (diffuser), and a light mask 16. The light source 12 is used to emit light. The diffuser 14 is used to diffuse the light emitted by the light source 12 to form a uniform light. The light mask 16 is used to project uniform light emitted from the diffuser 14 to form structured light. The diffuser 14 is located between the light source 12 and the light mask 16.

In the projection module 10 according to the embodiment of the present invention, a diffuser 14 is disposed between the light source 12 and the reticle 16 to diffuse the light emitted by the light source 12, and the distance between the light source 12 and the reticle 16 can be set relatively close, thereby facilitating the projection The miniaturized design of the group 10, meanwhile, diffused through the diffuser 14 can form uniform light, making the structured light formed by the light mask 16 better.

Specifically, referring to FIG. 3, uniform light refers to light having a certain light pattern distribution, density, and uniformity. That is to say, the diffuser 14 can diffuse light to form light with a certain light distribution, density, and uniformity.

Further, the addition of the diffuser 14 can reduce the sensitivity of the distance control between the light source 12 and the reticle 16, which is beneficial to improve the yield rate of the projection module 10 when the projection module 10 is assembled.

In one example, structured light includes coded structured light.

In some embodiments, the diffuser 14 may be made by adding a scattering material to the material layer, or by making scattering characteristics on the surface layer of the material layer, or by designing a diffractive microstructure on the surface of the material layer, or by A microlens array (Micro Lens Array, MLA) refractive microstructure is designed on the surface of the material layer. Specifically, the diffuser 14 can select different designs according to different uses and optical requirements, which can meet more scene requirements.

In some embodiments, the diffuser 14 is kept at a distance from the light source 12. In this way, the projection module 10 can meet the corresponding optical requirements. Wherein, the diffuser 14 and the light source 12 can be set at an appropriate distance according to different optical requirements.

Please refer to FIGS. 4 and 5. In some embodiments, the reticle 16 includes a light-transmitting region 162 and a light-shielding region 164. The light-transmitting region 162 forms a structured pattern.

It can be understood that the light cannot pass through the light-shielding area 164, for example, the light-shielding area 164 can block or absorb the light, so that when the light is projected to the reticle 16, the light-shielding area 164 is blocked and can exit from the light-transmitting area 162, due to light transmission The area 162 forms a structured pattern. Therefore, the light projected through the photomask 16 can form a structured light corresponding to the structured pattern, that is, the photomask 16 can project the light to form a structured light. Among them, the structured pattern includes, but is not limited to, a grid pattern, a dot pattern, or a line pattern. In the embodiment of FIG. 4, the structured pattern is a grid pattern, and the structured light is distributed like a grid (as shown in FIG. 5). It can be understood that, in other embodiments, the structured pattern may also be other patterns, which is not specifically limited herein.

Specifically, in some embodiments, the photomask 16 may be made by photomask etching technology. The light-transmitting material is covered with a layer of light-shielding material, and the light-shielding material of the light-transmitting region 162 is etched away by the photomask etching technique, while the light-shielding material of the light-shielding region 164 is retained.

In the embodiments of the present invention, the uniform light projected onto the reticle 16 can make the structured light projected by the reticle 16 have better quality.

Referring to FIG. 1, in some embodiments, the diffuser 14 and the light source 12 are spaced apart, and the diffuser 14 and the light mask 16 are spaced apart.

In this way, the diffuser 14 can be provided as an independent element between the light source 12 and the reticle 16, that is to say, the projection module 10 can add the diffuser 14 on the basis of the original element, so that the diffuser 14 can The light emitted by the light source 12 diffuses and makes the light distribution in the projection module 10 uniform.

Please refer to FIG. 2, in some embodiments, the diffuser 14 is disposed on the reticle 16.

That is to say, the diffuser 14 and the reticle 16 are provided integrally, so that they can be designed as one element. Similarly, the uniform light diffused by the diffuser 14 can be projected through the reticle 16 to form structured light. In addition, the diffuser 14 is disposed on the reticle 16 without increasing the number of components, optimizing the spatial arrangement of the projection module 10, which is beneficial to the assembly of the projection module 10.

Further, in some embodiments, when the diffuser 14 is disposed on the photomask 16, the light exit surface of the diffuser 14 may be covered with a layer of light-shielding material, and the light-transmitting area 162 of the photomask 16 may be blocked by the photomask etching technique The material is etched away, and the light-shielding material of the light-shielding area 164 of the photomask 16 remains. Of course, in other embodiments, the projection module 10 can also glue the diffuser 14 and the reticle 16 with glue, and fixedly connect to form an integrated structure.

In some embodiments, the projection module 10 includes a projection lens 18 (Projection Lens) located on the light-emitting side of the light mask 16, and the projection lens 18 is used to project structured light.

In this way, the projection module 10 can improve the effect of structured light projection through the projection lens 18 to achieve corresponding imaging quality. For example, line width, depth of field (Depth of Focus, DOF) and field of view (Field of View, FOV), etc. It can be understood that the line width corresponds to the precision of structured light projection, the depth of field corresponds to the effective distance and clarity of structured light projection, and the angle of view corresponds to the range of structured light projection.

In some embodiments, the projection lens 18 includes at least one optical lens. In one example, the projection lens 18 may be an optical lens. In another example, the projection lens 18 may be a combination of multiple optical lenses. In this way, the projection module 10 can improve the effect of structured light projection through the projection lens 18.

In some embodiments, the light source 12 includes a vertical cavity surface emitting laser array, and the vertical cavity surface emitting laser array includes a plurality of vertical cavity surface emitting lasers 122 distributed in an array.

It can be understood that the vertical cavity surface emitting laser 122 is a small-volume semiconductor laser, which can form an array distribution with a higher output power and is used to establish an efficient laser light source. In this way, the projection module 10 can use the vertical cavity surface emitting laser array as the light source 12, which can meet the small volume requirement of the light source 12, and the array distribution formed by multiple vertical cavity surface emitting lasers 122 can ensure the continuity of structured light projection.

Referring to FIG. 6, the imaging device 100 according to the embodiment of the present invention includes a receiving module 20 and the projection module 10 of any of the above embodiments.

The imaging device 100 of the embodiment of the present invention is the projection module 10 of the embodiment of the present invention. That is to say, the projection module 10 of the embodiment of the present invention can be applied to the imaging device 100 of the embodiment of the present invention.

The imaging device 100 according to an embodiment of the present invention may be used to collect three-dimensional contour information of an object. The imaging device 100 projects structured light to the space through the projection module 10. When the structured light is projected to an object in the space, the pattern formed by the structured light According to the change of the three-dimensional contour of the object, the receiving module 20 receives the pattern of the reflected light of the object, and the imaging device 100 calculates the three-dimensional information of the object according to the change of the reflected pattern of the object.

In the imaging device 100, a diffuser 14 is provided between the light source 12 and the reticle 16 of the projection module 10. The diffuser 14 can diffuse the light emitted by the light source 12, and the distance between the light source 12 and the reticle 16 can be set relatively close, thereby It is conducive to the miniaturized design of the projection module 10 and the imaging device 100. At the same time, the diffuser 14 diffuses to form a uniform light, making the structured light formed by the mask 16 better, and is beneficial to improve the imaging device 100 to detect three-dimensional information Accuracy.

In some embodiments, the receiving module 20 and the projection module 10 are arranged side by side. In this way, it is favorable for the projection module 10 to project the structured light and the light reflected by the object is received by the receiving module 20.

In some embodiments, the receiving module 20 includes an imaging lens 22 and an image sensor 24. The image sensor 24 is located on the image side of the imaging lens 22. The imaging lens 22 is used to concentrate incident light to the image sensor 24.

In this way, the image sensor 24 can collect the light reflected by the object, and the imaging lens 22 can condense the light to the image sensor 24, which is beneficial for the receiving module 20 to receive the structured light reflected by the projection module 10 after being projected onto the object.

In some embodiments, the imaging lens 22 includes at least one optical lens. In one example, the imaging lens 22 may be an optical lens. In another example, the imaging lens 22 may be a combination of multiple optical lenses. In this way, the receiving module 20 can improve the imaging effect of the image sensor 24 through the imaging lens 22.

In some embodiments, the receiving module 20 includes a filter 26 that is located between the imaging lens 22 and the image sensor 24.

In this way, the filter 26 can filter other light than the light projected by the projection module 10 to avoid interference of other light, so that the image information formed by the image sensor 24 collecting light is more accurate.

In one example, the projection module 10 can project infrared light, and the filter 26 can be an infrared filter. In this way, the infrared filter can filter non-infrared light to avoid interference of the non-infrared light on the image captured by the image sensor 24.

Referring to FIG. 7, the electronic device 1000 of the embodiment of the present invention includes the imaging device 100 of any of the above embodiments.

The electronic device 1000 of the embodiment of the present invention adopts the imaging device 100 of the embodiment of the present invention, that is, the imaging device 100 of the embodiment of the present invention can be applied to the electronic device 1000 of the embodiment of the present invention.

The electronic device 1000 can acquire the three-dimensional contour information of the object through the imaging device 100, thereby achieving more functions. For example, the electronic device 1000 can obtain three-dimensional contour information of a human face, thereby realizing functions such as face recognition and face unlock.

In the electronic device 1000, the projection module 10 of the imaging device 100 is provided with a diffuser 14 between the light source 12 and the reticle 16 to diffuse the light emitted by the light source 12, and the distance between the light source 12 and the reticle 16 can be relatively close, so that It is beneficial to the miniaturized design of the projection module 10, the imaging device 100, and the electronic device 1000. At the same time, the diffuser 14 diffuses to form a uniform light, making the structured light formed by the mask 16 better.

In some embodiments, the electronic device 1000 includes, but is not limited to, electronic devices such as mobile phones, tablet computers, notebook computers, smart wearable devices, door locks, vehicle-mounted terminals, and drones. In the example shown in FIG. 7, the electronic device 1000 is a mobile phone.

In the description of this specification, reference to the descriptions of the terms "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means combined embodiments The specific features, structures, materials, or characteristics described in the examples are included in at least one embodiment or example of the present invention. In this specification, the schematic expression of the above-mentioned terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, replacements, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, The scope of the invention is defined by the claims and their equivalents.

Claims

A projection module, characterized in that it includes:

A light source, the light source is used to emit light;

A diffuser for diffusing the light emitted by the light source to form a uniform light; and

A light mask, which is used to project uniform light emitted from the diffuser to form structured light, and the diffuser is located between the light source and the light mask.
The projection module according to claim 1, wherein the diffuser and the light source are spaced apart, and the diffuser and the photomask are spaced apart.
The projection module according to claim 1, wherein the diffuser is disposed on the reticle.
The projection module according to claim 1, wherein the diffuser can be made by adding a scattering material to the material layer, or by making a scattering property on the surface layer of the material layer, or by making a surface layer of the material layer It is made by designing diffractive microstructures, or by designing microlens array refraction microstructures on the surface of the material layer.
The projection module according to claim 1, wherein the photomask includes a light-transmitting area and a light-shielding area, and the light-transmitting area forms a structured pattern.
The projection module according to claim 1, characterized in that the projection module includes a projection lens on the light emitting side of the photomask, and the projection lens is used to project the structured light.
The projection module according to claim 1, wherein the light source includes a vertical cavity surface emitting laser array, and the vertical cavity surface emitting laser array includes a plurality of vertical cavity surface emitting lasers distributed in an array.
An imaging device, characterized in that it includes

A projection module, the projection module is used to project structured light; and

A receiving module, the receiving module is used to receive the light reflected by the structured light through the object;

The projection module includes:

A light source, the light source is used to emit light;

A diffuser for diffusing the light emitted by the light source to form a uniform light; and

A light mask, which is used to project uniform light emitted from the diffuser to form structured light, and the diffuser is located between the light source and the light mask.
The imaging device according to claim 8, wherein the diffuser and the light source are spaced apart, and the diffuser and the photomask are spaced apart.
The imaging device according to claim 8, wherein the diffuser is provided on the reticle.
The imaging device according to claim 8, wherein the diffuser can be made by adding a scattering material to the material layer, or by making a scattering property on the surface layer of the material layer, or by designing on the surface of the material layer Diffraction microstructures, or by designing microlens array refraction microstructures on the surface of the material layer.
The imaging device according to claim 8, wherein the photomask includes a light-transmitting area and a light-shielding area, the light-transmitting area forming a structured pattern.
The imaging device according to claim 8, wherein the projection module includes a projection lens located on the light exit side of the reticle, and the projection lens is used to project the structured light.
The imaging device according to claim 8, wherein the light source includes a vertical cavity surface emitting laser array, and the vertical cavity surface emitting laser array includes a plurality of vertical cavity surface emitting lasers distributed in an array.
The imaging device according to claim 8, wherein the receiving module includes an imaging lens and an image sensor, the image sensor is located on an image side of the imaging lens, and the imaging lens is used to collect incident light To the image sensor.
The imaging device according to claim 15, wherein the receiving module includes a filter, and the filter is located between the imaging lens and the image sensor.
The imaging device according to claim 8, wherein the receiving module and the projection module are arranged side by side.
An electronic device, characterized by comprising the imaging device according to any one of claims 8-17.