CN218547146U - Laser projection module, depth camera and electronic equipment - Google Patents

Abstract

The application provides a laser projection module, a depth camera and an electronic device. The laser projection module comprises two laser projectors, the laser projectors are used for projecting an emergent light beam to a target area to form a corresponding emergent light field, the two laser projectors are stacked and arranged along the vertical direction, the optical centers of the two laser projectors are overlapped in the horizontal direction, the two laser projectors are arranged in a staggered mode to enable the visual field ranges of the two laser projectors in the horizontal direction to be spliced with each other, and the visual field angle of the laser projection module in the horizontal direction is larger than that of a single laser projector in the horizontal direction. The application can effectively improve the angle of field of the laser projection module in the horizontal direction, thereby expanding the application of the laser projection module in more electronic equipment.

Description

Laser projection module, depth camera and electronic equipment

[ technical field ] A

The application relates to the technical field of optical ranging and imaging, in particular to a laser projection module, a depth camera and an electronic device.

[ background ] A method for producing a semiconductor device

With the continuous development and progress of 3D (3-Dimension) sensing technology, more and more electronic devices start to carry 3D sensing technology, which is not only embodied in the traditional industries such as mobile phones and tablet computers, but also embodied in the industries such as robots (e.g., sweeping robots, delivering/shipping robots, etc.), and especially during the global spread of the current new coronavirus pneumonia epidemic situation, the delivering/shipping robots are more highly developed in history. In electronic equipment, the 3D sensing technology is mainly embodied in depth imaging, which is generally implemented by a laser projection module and a laser receiving module that are disposed in the electronic equipment, wherein the laser projection module is configured to emit a light beam to a target area, and the laser receiving module is configured to receive a reflected light beam reflected by the target area from the emitted light beam, and generate a depth image of the target area according to the reflected light beam, thereby implementing a depth imaging function.

In the related art, the laser projection module generally includes a light source, a collimating lens and an optical diffraction element, wherein light emitted by the light source is collimated by the collimating lens and then enters the diffraction optical element, and the diffraction optical element copies a plurality of parts of the incident light and then projects the copied light to a target area to form a corresponding speckle light field. However, the field angle of the laser projection module is generally small, and two main reasons are: firstly, the larger the field angle is, the more the diffraction efficiency and the energy distribution of the speckle light field projected finally are reduced; secondly, the larger the field angle is, the smaller the speckle density around the speckle light field which is finally projected is, so that the speckle density on a matching window with a specified size cannot meet the requirement of the algorithm, and the algorithm cannot be matched. In short, the small angle of view of the laser projection module severely limits its application in various electronic devices.

Therefore, there is a need for an improved structure of the laser projection module.

[ Utility model ] A method for manufacturing a semiconductor device

The application provides a laser projection module, a depth camera and electronic equipment, and aims to solve the problem that the laser projection module in the related art is difficult to meet the requirement of a large field angle.

In order to solve the above technical problem, a first aspect of the embodiments of the present application provides a laser projection module, which includes two laser projectors for projecting outgoing light beams to a target area to form corresponding outgoing light fields, where the two laser projectors include two laser projectors stacked in a vertical direction, optical centers of the two laser projectors coincide in a horizontal direction, and the two laser projectors are staggered so that field ranges of the two laser projectors in the horizontal direction are spliced with each other, so that a field angle of the laser projection module in the horizontal direction is larger than that of a single laser projector in the horizontal direction; wherein the vertical direction indicates the direction of a connecting line between the two laser projectors, and the horizontal direction is perpendicular to the vertical direction.

In some embodiments, a laser projector includes a light source for emitting an exit beam, a collimating element for collimating the exit beam for projection onto a diffractive optical element, and a diffractive optical element for replicating the incident exit beam into portions for projection onto a target area to form a corresponding exit light field.

In some embodiments, the light source is a light source array including a plurality of sub light sources arranged in an array, wherein the plurality of sub light sources are preferably arranged in an irregular array.

In some embodiments, the array arrangement shapes of the plurality of sub light sources in the light source arrays in the two laser projectors are different.

In some embodiments, the light source arrays in the two laser projectors have the same array arrangement shape of the plurality of sub light sources, and the light source array in one laser projector is inclined to the light source array in the other laser projector by a preset angle.

In some embodiments, the angle of view of the laser projection module in the horizontal direction is equal to twice the angle of view of the single laser projector in the horizontal direction.

A second aspect of the embodiments of the present application provides a depth camera, which includes a laser projection module, a collector, and a control and processor according to the first aspect of the embodiments of the present application, wherein the control and processor are configured to: the control laser projection module sends out the outgoing beam to the target area to and control the collector and receive the reflected beam that the outgoing beam reflected through the target area, and generate the depth map of target area according to the reflected beam.

A third aspect of embodiments of the present application provides an electronic device including the depth camera of the second aspect of embodiments of the present application.

As can be seen from the above description, the present application has the following advantages compared with the related art:

the laser projection module comprises two laser projectors, wherein the two laser projectors are stacked up and down to enable optical centers of the two laser projectors to coincide in the vertical direction (namely the direction of a connecting line between the two laser projectors), and the two laser projectors are arranged in a staggered mode when stacked up and down to enable the visual field ranges of the two laser projectors in the horizontal direction (perpendicular to the vertical direction) to be spliced with each other, so that the purpose that the visual field angle of the laser projection module in the horizontal direction is larger than that of a single laser projector in the horizontal direction is achieved.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions in the related art or the embodiments of the present application, the drawings required to be used in the description of the related art or the embodiments of the present application will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, but not all embodiments, and that other drawings may be obtained by those skilled in the art without inventive efforts.

FIG. 1 (a) is a schematic structural diagram of a conventional laser projection module;

fig. 1 (b) is a schematic structural diagram of a laser projection module according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a laser projector according to an embodiment of the present disclosure;

FIG. 3 is a first comparative diagram of an array of light sources in two laser projectors provided by an embodiment of the present application;

FIG. 4 is a second comparison of an array of light sources in two laser projectors provided by an embodiment of the present application;

fig. 5 is a schematic structural diagram of a depth camera according to an embodiment of the present application.

[ detailed description ] embodiments

In order to make the objectives, technical solutions and advantages of the present application more obvious and understandable, the present application will be clearly and completely described below in conjunction with the embodiments of the present application and the corresponding drawings, wherein the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. It should be understood that the embodiments of the present application described below are only for explaining the present application and are not intended to limit the present application, that is, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts based on the embodiments of the present application belong to the protection scope of the present application. In addition, the technical features involved in the embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

Fig. 1 (a) is a schematic structural diagram of a conventional laser projection module. In the conventional solution, in order to improve the field angle of the laser projection module, especially the horizontal field angle, two laser projectors 10 are usually used to project speckle pattern beams to the space area 101, the two laser projectors 10 are placed next to each other along the horizontal direction (x direction), and the emergent light direction is the z direction, in this placement manner, the optical centers 1021, 1022 of the two laser projectors 10 have a certain distance in the horizontal direction, so that the projected beams have an un-illuminated area 1012 in the space area 101, and 1011 in the space area 101 corresponds to the overlapping area of the two beams, so that the light beams are not uniformly distributed in the whole field of view, thereby resulting in that the accuracy of the depth camera measurement using the laser projection module is not high. To solve this problem, the embodiment of the present application provides a laser projection module shown in fig. 1 (b), which still includes two laser projectors 10 in the existing laser projection module, and each laser projector 10 is used to project an outgoing beam to a target area to form a corresponding outgoing light field, where the outgoing beam is a speckle pattern beam.

Specifically, two laser projectors 10 are stacked in a vertical direction (as shown in fig. 1 (a), a direction perpendicular to a plane in which an x direction and a z direction are located, that is, a direction perpendicular to a paper surface) (that is, one laser projector 10 is disposed on the other laser projector 10), optical centers 1021 and 1022 of the two laser projectors 10 are overlapped in a horizontal direction (since the two are overlapped in the horizontal direction, fig. 1 (b) only marks 1021), and the two laser projectors 10 are disposed in a staggered manner when stacked so that the field ranges of the two laser projectors 10 in the horizontal direction are spliced with each other, so that the field angle of the laser projection module in the horizontal direction is larger than the field angle of the single laser projector 10 in the horizontal direction. In fig. 1 (b), a region 1031 between two solid arrows indicates a field range of one laser projector 10 in the horizontal direction, and a region 1032 between two dotted arrows indicates a field range of another laser projector 10 in the horizontal direction, and in the conventional installation process, if two laser projectors 10 are stacked only in the vertical direction, the field ranges projected by the two laser projectors 10 also overlap in the vertical direction and cannot achieve the effect of expanding the field in the horizontal direction, and therefore, the two laser projectors 10 are installed in a staggered manner, that is, the light beams projected by the two laser projectors 10 do not overlap in the vertical direction.

In the present embodiment, the two laser projectors 10 are arranged in a staggered manner when stacked, rather than in an aligned manner, and the purpose is to make the projection directions of the two laser projectors 10 at a certain angle to each other, because only the range of the fields of view of the two laser projectors 10 in the horizontal direction can be spliced. The optical centers of the two laser projectors 10 are overlapped in the horizontal direction, but not staggered, so that when the distance between the laser projection module and the target area is changed, the distance between the laser projection module and each speckle block in the emergent light field projected by the target area in the horizontal direction can still be kept unchanged. In addition, if the field of view ranges of the two laser projectors 10 in the horizontal direction are only spliced and do not overlap, the field angle of the laser projection module in the horizontal direction is equal to twice the field angle of the single laser projector 10 in the horizontal direction; if the field ranges of the two laser projectors 10 in the horizontal direction overlap, the field angle of the laser projection module in the horizontal direction is less than twice of the field angle of the single laser projector 10 in the horizontal direction, but still greater than the field angle of the single laser projector 10 in the horizontal direction; preferably, the field of view ranges of the two laser projectors 10 in the horizontal direction are only spliced without overlapping, so that the field angle of the laser projection module in the horizontal direction is equal to twice the field angle of the single laser projector 10 in the horizontal direction.

In practical application, the most typical application scene of laser projection module is exactly the degree of depth formation of image, can project the laser beam to the regional emission of target through the laser projection module that this application embodiment provided, later can be according to the reflection beam generation target area's of emergent beam through the regional reflection of target depth image to realize the degree of depth formation of image function.

In the embodiment of the present application, two laser projectors 10 are adopted to form a laser projection module, the two laser projectors 10 are stacked together up and down, so that the optical centers of the two laser projectors 10 overlap each other in the horizontal direction, and the two laser projectors 10 are staggered when stacked up and down, so that the field ranges of the two laser projectors 10 in the horizontal direction are spliced together, thereby achieving the purpose that the field angle of the laser projection module in the horizontal direction is larger than that of a single laser projector 10 in the horizontal direction. Experiments prove that the angle of field of the laser projection module provided by the embodiment of the application in the horizontal direction can reach more than 100 degrees.

In some embodiments, please further refer to fig. 2, fig. 2 is a schematic structural diagram of a laser projector according to an embodiment of the present disclosure. The laser projector 10 includes a light source 11, a collimating element 12 and a diffractive optical element 13, wherein the light source 11 is configured to emit an outgoing light beam, the collimating element 12 is configured to collimate the outgoing light beam to be projected to the diffractive optical element 13, and the diffractive optical element 13 is configured to copy some parts of the incoming outgoing light beam to be projected to a target area to form a corresponding outgoing light field. Of course, in other embodiments, the laser projector 10 may also include other structures commonly used in the art, such as a circuit board 14 and a housing 15, the circuit board 14 being used to carry the light source 11 and various circuits that enable the normal operation of the laser projector 10, and the housing 15 being used to house, support, and protect the circuit board 14, the light source 11, the collimating element 12, and the diffractive optical element 13.

In this embodiment, the collimating element 12 may be composed of at least one collimating lens, and the light source 11 may adopt a light source array including a plurality of sub light sources 111 arranged in an array (see fig. 3 or fig. 4), and for the shape of the array arrangement of the plurality of sub light sources 111 in the light source array, the shape may be any shape, including but not limited to a rectangle, a trapezoid, a circle, an ellipse, and a polygon, which is not limited in this embodiment. Preferably, the sub-light source 111 may be a Vertical Cavity Surface Emitting Laser (VCSEL), which has the advantages of small size and low power consumption, and is advantageous for the laser projection module to be integrated in a miniature electronic device. In addition, in the present embodiment, the plurality of sub light sources 111 in the light source array are arranged in an irregular array, because only the array arrangement of the plurality of sub light sources 111 in the light source array is irregular, the speckle pattern beam can be projected to the target area after being collimated by the collimating element 12 and replicated by the diffractive optical element 13.

As an embodiment, please further refer to fig. 3, fig. 3 is a first comparison diagram of the light source arrays in the two laser projectors according to the embodiment of the present application. The collimation diameters of the emitted light beams by the two laser projectors 10 are the same, and the two laser projectors 10 use the diffractive optical element 13 having the same structure, but the array arrangement shapes of the plurality of sub light sources 111 in the light source arrays in the two laser projectors 10 are different from each other. In fig. 3, (1) of fig. 3 shows an array arrangement shape of the plurality of sub light sources 111 in the light source array in one laser projector 10, and (2) of fig. 3 shows an array arrangement shape of the plurality of sub light sources 111 in the light source array in another laser projector 10.

If the array arrangement shapes of the sub light sources 111 in the light source arrays in the two laser projectors 10 are the same, then the laser projection module projects a speckle light field on a target area, two similar scattered patches appear in the two light field areas corresponding to the two laser projectors 10, and the distribution of the speckles in each speckle block is consistent with the array distribution of the sub light sources 111 in the light source array, which causes a phenomenon of misidentification when similarity matching is performed, and further causes a parallax error calculation, so the array arrangement shapes of the sub light sources 111 in the light source arrays in the two laser projectors 10 in the embodiment are different from each other, and the purpose is to enable the laser projection module to generate no similar speckle block in the speckle light field in the target area, and improve the randomness of the speckle light field.

In another embodiment, referring to fig. 4, fig. 4 is a second comparison diagram of the light source arrays in the two laser projectors according to the embodiment of the present application. Compared with the previous embodiment, the embodiment provides another way for improving the randomness of the speckle light field, and the method comprises the following steps: the collimation diameters of the emitted light beams of the two laser projectors 10 are the same, the two laser projectors 10 adopt the diffraction optical element 13 with the same structure, the array arrangement shapes of the plurality of sub light sources 111 in the light source arrays in the two laser projectors 10 are the same, but the light source array in one laser projector 10 is arranged in an inclined way by a preset angle relative to the light source array in the other laser projector 10. In fig. 4, fig. 4 (1) shows a state in which the light source array in one laser projector 10 is placed with reference to its housing 15, and fig. 4 (2) shows a state in which the light source array in another laser projector 10 is placed with reference to its housing 15, it can be seen that the light source array in fig. 4 (2) is placed obliquely, and for the sake of understanding, we can refer to a state in which the light source array in fig. 4 (1) is placed with respect to its housing 15 as a forward direction placement state, and refer to a state in which the light source array in fig. 4 (2) is placed with respect to its housing 15 as an oblique placement state.

It should be noted that the above embodiment is only a preferred implementation of the present embodiment, and is not the only limitation on the arrangement form of the light source arrays in the two laser projectors 10; in this regard, those skilled in the art can flexibly set the setting according to the actual application scenario based on the embodiment.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a depth camera according to an embodiment of the present disclosure. The embodiment of the present application further provides a depth camera, which includes a transmitter, a collector, and a control and processor, wherein the control and processor are configured to: controlling the emitter to emit a beam to the target area, controlling the collector to receive a reflected beam of the emitted beam reflected by the target area, and generating a depth image of the target area according to the reflected beam; wherein, the transmitter includes the aforesaid laser projection module that this application embodiment provided.

As mentioned above, the light source 11 in the laser projection module (i.e. the emitter) may be a light source array including a plurality of sub-light sources 111 arranged in an irregular array, in which case the control and processor controls all the sub-light sources 111 in the light source array to emit light to project the speckle pattern beam onto the target area. It can be understood that the depth camera is mainly used for acquiring a depth image of a target area, which requires scanning the target area, so that the embodiment of the present application needs to control all the sub-light sources 111 in the light source array to emit light, rather than controlling some of the sub-light sources 111 in the light source array to emit light.

Therefore, according to the depth camera provided by the embodiment of the application, the emitter in the depth camera adopts the laser projection module provided by the embodiment of the application, so that a larger field angle can be obtained in the horizontal direction to meet the requirements of the depth camera in various different application scenes.

In addition, the embodiment of the application further provides an electronic device, and the electronic device comprises the depth camera provided by the embodiment of the application. It can be understood that, when the electronic device needs to have a depth imaging function, it is sufficient to set the aforementioned depth camera provided in the embodiments of the present application; for example, electronic devices such as a sweeping robot and a meal/delivery robot need to have a depth imaging function, in which case the depth camera provided in the embodiments of the present application needs to be arranged to sense the surrounding environment in advance, that is, the depth camera may detect the surrounding environment in real time to determine whether there is an obstacle, so as to plan the next action and the travel path.

It should be noted that, the embodiments in the present disclosure are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

It should also be noted that, in the present application, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended 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.

Claims (10)

1. A laser projection module comprises a laser projector, wherein the laser projector is used for projecting an emergent light beam to a target area to form a corresponding emergent light field; it is characterized in that the preparation method is characterized in that,

the laser projectors comprise two lasers which are stacked along the vertical direction, and the optical centers of the two lasers coincide in the horizontal direction;

the two laser projectors are arranged in a staggered mode so that the visual field ranges of the two laser projectors in the horizontal direction are spliced with each other, and the visual field angle of the laser projection module in the horizontal direction is larger than that of a single laser projector in the horizontal direction;

wherein the vertical direction indicates a direction of a connecting line between the two laser projectors, and the horizontal direction is perpendicular to the vertical direction.

2. The laser projection module of claim 1, wherein the laser projector comprises a light source, a collimating element, and a diffractive optical element, wherein the light source is configured to emit the outgoing light beam, the collimating element is configured to collimate the outgoing light beam for projection onto the diffractive optical element, and the diffractive optical element is configured to replicate the incoming outgoing light beam in portions for projection onto the target area to form the corresponding outgoing light field.

3. The laser projection module of claim 2, wherein the light source is a light source array comprising a plurality of sub-light sources arranged in an array.

4. The laser projection module of claim 3, wherein the plurality of sub-light sources are arranged in an irregular array.

5. The laser projection module of claim 4, wherein the arrangement shapes of the plurality of sub light sources in the light source arrays in two laser projectors are different.

6. The laser projection module of claim 4, wherein the light source arrays in the two laser projectors have the same array arrangement shape of the sub light sources, and the light source array in one laser projector is inclined at a predetermined angle with respect to the light source array in the other laser projector.

7. The laser projection module of claim 1, wherein the angle of view of the laser projection module in the horizontal direction is equal to twice the angle of view of a single laser projector in the horizontal direction.

8. A depth camera comprising the laser projection module of any one of claims 1-7, a collector, and a control and processor, wherein the control and processor is configured to:

controlling the laser projection module to emit an emergent beam to a target area, controlling the collector to receive a reflected beam of the emergent beam reflected by the target area, and generating a depth image of the target area according to the reflected beam.

9. The depth camera of claim 8, wherein the light source in the laser projection module is a light source array comprising a plurality of sub-light sources arranged in an irregular array, and the control and processor is specifically configured to control all the sub-light sources in the light source array to emit light so that the laser projection module projects a speckle pattern beam onto the target area.

10. An electronic device comprising a depth camera as claimed in claim 8 or 9.

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