WO2020038060A1

WO2020038060A1 - Laser projection module and control method therefor, and image acquisition device and electronic apparatus

Info

Publication number: WO2020038060A1
Application number: PCT/CN2019/090074
Authority: WO
Inventors: 韦怡
Original assignee: Oppo广东移动通信有限公司
Priority date: 2018-08-22
Filing date: 2019-06-05
Publication date: 2020-02-27
Also published as: CN109151271A

Abstract

A laser projection module (100), a control method for the laser projection module (100), a depth image acquisition device (300) and an electronic apparatus (800). The laser projection module (100) comprises a light source (10), a diffuser (20), light detectors (63) and a processor (65). The light source (10) is used to emit a laser. The diffuser (20) is used to diffuse the laser. Each of the light detectors (63) is used to receive the laser reflected back from the diffuser (20) to form a light detection electric signal. The processor (65) is used to determine whether the diffuser (20) is abnormal according to the light detection signal.

Description

Laser projection module and control method thereof, image acquisition equipment and electronic device

Priority information

This application claims the priority and rights of a patent application filed with the State Intellectual Property Office of China on August 22, 2018, with a patent application number of 201810963384.5, and the entirety of which is incorporated herein by reference.

Technical field

The present invention relates to the field of three-dimensional imaging technology, and in particular, to a laser projection module, a method for controlling a laser projection module, a depth image acquisition device, and an electronic device.

Background technique

Time of flight (TOF) imaging system can calculate the depth information of the measured object by calculating the time difference between the time when the laser projection module emits the optical signal and the time when the optical receiver receives the optical signal. Laser projection modules typically include a light source and a diffuser. The light from the light source is diffused by the diffuser and then casts a uniform surface light into the scene.

Summary of the Invention

Embodiments of the present invention provide a laser projection module, a method for controlling the laser projection module, a depth image acquisition device, and an electronic device.

A laser projection module according to an embodiment of the present invention includes a light source, a diffuser, a light detector, and a processor. The light source is used for emitting laser light. The diffuser is used to diffuse the laser light. The light detector is used for receiving the laser light reflected by the diffuser to form a light detection electric signal. The processor is configured to determine whether the diffuser is abnormal according to the light detection signal.

A method for controlling a laser projection module according to an embodiment of the present invention. The laser projection module includes a light source, a diffuser, and a light detector. The light source is used to emit laser light. The diffuser is used to diffuse the laser light. The light detection The receiver is used for receiving the laser light reflected by the diffuser to form a light detection electric signal. The control method includes: acquiring the light detection electric signal output by the light detector; and determining whether the diffuser is abnormal according to the light detection signal.

A depth image acquisition device according to an embodiment of the present invention includes the above-mentioned laser projection module and a light receiver. The light receiver is configured to receive laser light emitted by the laser projection module.

An electronic device according to an embodiment of the present invention includes a casing and the above-mentioned depth image acquisition device. The depth image acquisition device is disposed on the casing.

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

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG. 1 and FIG. 2 are three-dimensional structure diagrams of an electronic device according to some embodiments of the present invention.

FIG. 3 is a schematic diagram of a three-dimensional structure of a depth image acquisition device according to some embodiments of the present invention.

FIG. 4 is a schematic plan view of a depth image acquisition device according to some embodiments of the present invention.

FIG. 5 is a schematic cross-sectional view of the depth image acquisition device in FIG. 4 along the V-V line.

FIG. 6 is a schematic structural diagram of a laser projection module according to some embodiments of the present invention.

FIG. 7 is a schematic diagram of an arrangement of photodetectors in some embodiments of the present invention.

8 to 11 are schematic flowcharts of a method for controlling a laser projection module according to some embodiments of the present invention.

detailed description

The following further describes the embodiments of the present invention with reference to the accompanying drawings. The same or similar reference numerals in the drawings represent the same or similar elements or elements having the same or similar functions throughout.

In addition, the embodiments of the present invention described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of the present invention, and should not be construed as limiting the present invention.

The laser projection module 100 includes a light source 10, a diffuser 20, a light detector 63, and a processor 65. The light source 10 is used to emit laser light. The diffuser 20 is used to diffuse laser light. The photodetector 63 is used to receive the laser light reflected by the diffuser 20 to form a photodetection electrical signal. The processor 65 is configured to determine whether the diffuser 20 is abnormal according to the light detection signal.

In some embodiments, the processor 65 is configured to determine whether the light detection signal exceeds a preset range, and determine that the diffuser 20 is abnormal when the light detection signal exceeds the preset range.

In some embodiments, the processor 65 is configured to determine whether the diffuser 20 is abnormal according to the light detection signal and the driving current of the light source 10.

In some embodiments, the processor 65 is further configured to control the light source 10 to be turned off when the diffuser 20 is abnormal.

In some embodiments, the light detector 63 includes a plurality of light detectors 63, and the plurality of light detectors 63 are arranged symmetrically around the light source 10.

The laser projection module 100 includes a light source 10, a diffuser 20, a light detector 63, and a processor 65. The light source 10 is used to emit laser light. The diffuser 20 is used to diffuse laser light. The photodetector 63 is used to receive the laser light reflected by the diffuser 20 to form a photodetection electrical signal. The control method of the laser projection module 100 includes:

01: Obtaining the light detection electric signal output by the light detector 63; and

03: Determine whether the diffuser 20 is abnormal according to the light detection signal.

In some embodiments, step 03 includes:

031: determine whether the light detection signal exceeds the preset range; and

032: It is determined that the diffuser 20 is abnormal when the light detection signal exceeds the preset range.

In some embodiments, step 03 may further include:

033: Determine whether the diffuser 20 is abnormal according to the light detection signal and the driving current of the light source 10.

In some embodiments, the control method after step 03 further includes:

05: The light source 10 is controlled to be turned off when the diffuser 20 is abnormal.

The photodetector 63 includes a plurality of photodetectors 63, and the photodetectors 63 are arranged symmetrically around the light source 10.

The depth image acquisition device 300 includes the laser projection module 100 and the light receiver 200 of any one of the foregoing embodiments. The light receiver 200 is configured to receive laser light emitted by the laser projection module 100.

The electronic device 800 includes a casing 801 and the depth image acquisition device 300 of any one of the foregoing embodiments, and the depth image acquisition device 300 is disposed on the casing 801.

Please refer to FIG. 1 and FIG. 2 together. An electronic device 800 according to an embodiment of the present invention includes a casing 801 and a depth image acquisition device 300. The electronic device 800 may be a mobile phone, a tablet computer, a game console, a smart watch, a smart bracelet, a headset device, a drone, and the like. The embodiment of the present invention is described by taking the electronic device 800 as a mobile phone as an example. It can be understood that the specific form of the electronic device 800 is not limited to a mobile phone.

The housing 801 may serve as a mounting carrier for the functional elements of the electronic device 800. The housing 801 can provide protection for the functional elements from dust, drop, and water. The functional elements can be a display screen 802, a visible light camera 400, a receiver, and the like. In the embodiment of the present invention, the housing 801 includes a main body 803 and a movable bracket 804. The movable bracket 804 can be moved relative to the main body 803 under the driving of a driving device. For example, the movable bracket 804 can slide relative to the main body 803 to slide. Move into the main body 803 (as shown in FIG. 1) or slide out from the main body 803 (as shown in FIG. 2). Some functional elements (such as the display 802) can be installed on the main body 803, and other functional elements (such as the depth image acquisition device 300, the visible light camera 400, and the receiver) can be installed on the movable bracket 804, and the movement of the movable bracket 804 can be driven The other functional element is retracted into or protruded from the main body 803. Of course, FIG. 1 and FIG. 2 are merely examples of a specific form of the casing 801, and cannot be understood as a limitation on the casing 801 of the present invention.

The depth image acquisition apparatus 300 is mounted on a casing 801. Specifically, the casing 801 may be provided with an acquisition window, and the depth image acquisition device 300 is installed in alignment with the acquisition window so that the depth image acquisition device 300 acquires depth information. In a specific embodiment of the present invention, the depth image acquisition device 300 is mounted on a movable bracket 804. When the user needs to use the depth image acquisition device 300, he can trigger the movable bracket 804 to slide out from the main body 803 to drive the depth image acquisition device 300 to protrude from the main body 803; when the depth image acquisition device 300 is not needed, he can trigger The movable bracket 804 slides into the main body 803 to drive the depth image acquisition device 300 to retract into the main body. In the real-time example of the present invention, the depth image acquisition device 300 is a time-of-flight (TOF) depth camera. Of course, FIG. 1 and FIG. 2 are only examples of a specific form of the casing 801, and cannot be understood as a limitation on the casing 801 of the present invention. For example, in another example, the acquisition window opened on the casing 801 The depth image acquisition device 300 may be fixed and aligned with the acquisition window. In another example, the depth image acquisition device 300 is fixed below the display screen 802.

Please refer to FIGS. 3 to 5 together. The depth image acquisition device 300 includes a first substrate assembly 71, a spacer 72, a laser projection module 100 and a light receiver 200. The first substrate assembly 71 includes a first substrate 711 and a flexible circuit board 712 connected to each other. The spacer 72 is disposed on the first substrate 711. The laser projection module 100 is configured to project laser light outward, and the laser projection module 100 is disposed on the pad 72. The flexible circuit board 712 is bent and one end of the flexible circuit board 712 is connected to the first substrate 711 and the other end is connected to the laser projection module 100. The light receiver 200 is disposed on the first substrate 711. The light receiver 200 is configured to receive laser light reflected by a person or an object in the target space. The light receiver 200 includes a housing 741 and an optical element 742 provided on the housing 741. The housing 741 is integrally connected with the pad 72.

Specifically, the first substrate assembly 71 includes a first substrate 711 and a flexible circuit board 712. The first substrate 711 may be a printed wiring board or a flexible wiring board. The control circuit and the like of the depth image acquisition device 300 may be laid on the first substrate 71. One end of the flexible circuit board 712 may be connected to the first substrate 711, and the other end of the flexible circuit board 712 is connected to the circuit board 50 (shown in FIG. 5). The flexible circuit board 712 can be bent at a certain angle, so that the relative positions of the devices connected at both ends of the flexible circuit board 712 can be selected.

The spacer 72 is disposed on the first substrate 711. In one example, the spacer 72 is in contact with the first substrate 711 and is carried on the first substrate 711. Specifically, the spacer 72 may be combined with the first substrate 711 by means of adhesion or the like. The material of the spacer 72 may be metal, plastic, or the like. In the embodiment of the present invention, a surface where the pad 72 is combined with the first substrate 711 may be a flat surface, and a surface opposite to the combined surface of the pad 72 may be a flat surface, so that the laser projection module 100 is disposed on the pad 72. It has better smoothness.

The light receiver 200 is disposed on the first substrate 711, and the contact surface between the light receiver 200 and the first substrate 711 is substantially flush with the contact surface between the pad 72 and the first substrate 711 (that is, the installation starting point of the two is at On the same plane). Specifically, the light receiver 200 includes a housing 741 and an optical element 742. The casing 741 is disposed on the first substrate 711, and the optical element 742 is disposed on the casing 741. The casing 741 may be a lens holder and a lens barrel of the light receiver 200, and the optical element 742 may be an element such as a lens disposed in the casing 741. Further, the light receiver 200 further includes a photosensitive chip (not shown), and the laser light reflected by a person or an object in the target space passes through the optical element 742 and is irradiated into the photosensitive chip, and the photosensitive chip generates a response to the laser. In the embodiment of the present invention, the housing 741 and the cushion block 72 are integrally connected. Specifically, the casing 741 and the cushion block 72 may be integrally formed; or the materials of the casing 741 and the cushion block 72 are different, and the two are integrally formed by two-color injection molding or the like. The housing 741 and the spacer 72 may also be separately formed, and the two form a matching structure. When assembling the depth image acquisition device 300, one of the housing 741 and the spacer 72 may be set on the first substrate 711, and then the other One is disposed on the first substrate 711 and connected integrally.

In this way, the laser projection module 100 is disposed on the cushion block 72. The cushion block 72 can raise the height of the laser projection module 100, thereby increasing the height of the surface on which the laser projection module 100 emits laser light. The laser light is not easily blocked by the light receiver 200, so that the laser light can be completely irradiated on the measured object in the target space.

With reference to FIG. 6, the laser projection module 100 includes a light source 10, a diffuser 20, a lens barrel 30, a protective cover 40, a circuit board 50, a driver 61, a light detector 63, and a processor 65.

The lens barrel 30 includes a ring-shaped lens barrel sidewall 33, and the ring-shaped lens barrel sidewall 33 surrounds a receiving cavity 62. The side wall 33 of the lens barrel includes an inner surface 331 located in the receiving cavity 62 and an outer surface 332 opposite to the inner surface. The side wall 33 of the lens barrel includes a first surface 31 and a second surface 32 opposite to each other. The receiving cavity 62 penetrates the first surface 31 and the second surface 32. The first surface 31 is recessed toward the second surface 32 to form a mounting groove 34 communicating with the receiving cavity 62. The bottom surface 35 of the mounting groove 34 is located on a side of the mounting groove 34 remote from the first surface 31. The outer surface 332 of the side wall 33 of the lens barrel is circular at one end of the first surface 31, and the outer surface 332 of the side wall 33 of the lens barrel is formed with an external thread at one end of the first surface 31.

The circuit board 50 is disposed on the second surface 32 of the lens barrel 30 and closes one end of the receiving cavity 62. The circuit board 50 may be a flexible circuit board or a printed circuit board.

The light source 10 is carried on the circuit board 50 and received in the receiving cavity 62. The light source 10 is configured to emit laser light toward the first surface 31 (the mounting groove 34) side of the lens barrel 30. The light source 10 may be a single-point light source or a multi-point light source. When the light source 10 is a single-point light source, the light source 10 may specifically be an edge-emitting laser, for example, a distributed feedback laser (Distributed Feedback Laser, DFB), etc .; when the light source 10 is a multi-point light source, the light source 10 may specifically be vertical A cavity-surface emitter (Vertical-Cavity Surface Laser, VCSEL), or the light source 10 may also be a multi-point light source composed of multiple edge-emitting lasers. The height of the vertical cavity surface emitting laser is small, and the use of the vertical cavity surface emitter as the light source 10 is beneficial to reduce the height of the laser projection module 100, and it is convenient to integrate the laser projection module 100 into a mobile phone, etc., which has a high thickness of the fuselage. The requirements of the electronic device 800. Compared with the vertical cavity surface emitter, the temperature drift of the side-emitting laser is smaller, and the influence of the temperature on the effect of the projected laser light from the light source 10 can be reduced.

The driver 61 is carried on the circuit board 50 and is electrically connected to the light source 10. Specifically, the driver 61 may receive the input signal modulated by the processor 65, and convert the input signal into a constant current source and transmit it to the light source 10, so that the light source 10 is directed toward the first position of the lens barrel 30 under the action of the constant current source. The one side 31 emits laser light. The driver 61 of this embodiment is provided outside the lens barrel 30. In other embodiments, the driver 61 may be disposed in the lens barrel 30 and carried on the circuit board 50.

The diffuser 20 is mounted (supported) in the mounting groove 34 and abuts the mounting groove 34. The diffuser 20 is used to diffuse the laser light passing through the diffuser 20. That is, when the light source 10 emits laser light toward the first surface 31 side of the lens barrel 30, the laser light passes through the diffuser 20 and is diffused or projected outside the lens barrel 30 by the diffuser 20.

The protective cover 40 includes a top wall 41 and a protective sidewall 42 extending from one side of the top wall 41. A light through hole 401 is defined in the center of the top wall 41. The protective side wall 42 is disposed around the top wall 41 and the light through hole 401. The top wall 41 and the protection side wall 42 together form a mounting cavity 43, and the light-passing hole 401 communicates with the mounting cavity 43. The cross-section of the inner surface of the protective sidewall 42 is circular, and an inner thread is formed on the inner surface of the protective sidewall 42. The internal thread of the protective sidewall 42 is screwed with the external thread of the lens barrel 30 to mount the protective cover 40 on the lens barrel 30. The interference between the top wall 41 and the diffuser 20 causes the diffuser 20 to be sandwiched between the top wall 41 and the bottom surface 35 of the mounting groove 34.

In this way, the opening 20 is installed in the lens barrel 30, and the diffuser 20 is installed in the installation groove 34, and the protective cover 40 is installed on the lens barrel 30 to clamp the diffuser 20 between the protective cover 40 and the installation groove. Between the bottom surfaces 35 of 34, the diffuser 20 is fixed on the lens barrel 30. In this way, it is not necessary to fix the diffuser 20 to the lens barrel 30 by using glue, which can prevent the gas glue from diffusing and solidifying on the surface of the diffuser 20 after the glue is volatilized to affect the microstructure of the diffuser 20, and can avoid diffusion The diffuser 20 falls off from the lens barrel 30 when the glue of the device 20 and the lens barrel 30 decreases due to aging.

With continued reference to FIG. 6, the light detector 63 is disposed on the circuit board 50 and is housed in the receiving cavity 62. The light transmittance of the diffuser 20 usually cannot reach 100%. Most of the laser light emitted by the light source 10 will be diffused out by the diffuser 20, but a small part of the laser light will be reflected by the diffuser 20. The light detector 63 can be used for receiving the laser light reflected by the diffuser 20. After receiving the laser light reflected from the diffuser 20, the photodetector 63 forms a photodetection electrical signal output. The processor 65 may receive the light detection electric signal output from the light detector 63 and determine whether the diffuser 20 is abnormal according to the light detection electric signal.

Specifically, the processor 65 may be used to determine whether the light detection signal exceeds the preset range. When the light detection signal exceeds the preset range, it indicates that the laser light received by the light detector 63 is more or less. The reason for this phenomenon may occur It is because the diffuser 20 is dirty that the emitted laser light is reduced and the laser light reflected back to the photodetector 63 is increased, or the diffuser 20 is broken and the emitted laser light is increased, the laser light reflected back to the photodetector 63 is reduced, or the diffuser 20 is detached As a result, the laser light is almost completely emitted, the laser light reflected back to the photodetector 63 is substantially zero, and so on. That is, when the light detection signal exceeds the preset range, it can be determined that the diffuser 20 is abnormal. When the light detection signal is within a preset range, it can be determined that the diffuser 20 is normal.

In addition, when the driving current of the light source 10 is large, the laser energy emitted by the light source 10 is also large, and the laser light received by the photodetector 63 is also large. When the driving current of the light source 10 is small, the laser energy emitted by the light source 10 is also large. It is smaller, and the laser light received by the photodetector 63 is less. Therefore, in order to improve the accuracy of the abnormality judgment of the diffuser 20, the processor 65 may determine whether the diffuser 20 is abnormal according to the light detection signal and the driving current of the light source 10. Specifically, the processor 65 may determine the preset range according to the driving current of the light source 10, for example, the driving current of the light source 10 is 1 amp. At this time, the current of the light detection signal formed by the light detector 63 when the diffuser 20 is normal is obtained through experiments at 600. Microamps, for example, the preset range can be determined to be 400 microamps to 800 microamps. It can be understood that the above 1A, 600 microamperes, 400 microamperes to 800 microamperes, and the like are all exemplary descriptions. After the preset range is determined according to the driving current, it can be determined whether the diffuser 20 is abnormal according to the determined preset range and the light detection signal.

Further, when the diffuser 20 is abnormal, the processor 65 may reduce the driving current of the light source 10 or directly control the light source 10 to be turned off, so as to prevent the emitted laser energy from being too high and causing damage to the human eye. In addition, when the diffuser 20 is abnormal, the laser projection module 100 generally cannot work normally, and turning off the light source 10 can reduce unnecessary power consumption.

When the diffuser is abnormal, the emitted light hits the user, which may cause safety problems. In summary, the laser projection module 100, the depth image acquisition device 300, and the electronic device 800 according to the embodiments of the present invention are provided with a light detector 63 on the laser projection module 100, and based on the light detection electric signal output by the light detector 63 It is determined whether the diffuser 20 is abnormal, so that countermeasures can be taken when the diffuser 20 is abnormal, such as turning off the light source 10 and reducing the driving current of the light source 10, thereby improving the safety of the user.

Please refer to FIG. 7. In some embodiments, the number of the light detectors 63 is multiple, and the plurality of light detectors 63 are arranged symmetrically around the light source 10 in the center. In this way, the multiple photodetectors 63 can receive more laser light reflected by the diffuser 20. After the processor 65 receives a plurality of light detection electric signals, it first sums and averages the plurality of light detection electric signals to obtain an average value of the plurality of light detection electric signals, and then uses the average value of the light detection electric signals to a preset range. In comparison, if the average value of the light detection electric signal exceeds the preset range, it is determined that the diffuser 20 is abnormal; if the average value of the light detection electric signal is within the preset range, the processor 65 does not perform an action. Using a plurality of photodetectors 63 disposed at different positions to receive the laser light reflected by the diffuser 20 can more accurately detect the amount of laser light reflected by the diffuser 20, and further, the diffuser 20 can be detected more accurately. Whether or not it is abnormal helps the processor 65 to control the light source 10 more accurately.

Please refer to FIG. 2 to FIG. 5 together. In some embodiments, the side where the cushion block 72 is combined with the first substrate 711 is provided with a receiving cavity 723. The depth image acquisition apparatus 300 further includes an electronic component 77 provided on the first substrate 711. The electronic component 77 is housed in the receiving cavity 723. The electronic component 77 may be an element such as a capacitor, an inductor, a transistor, or a resistor. The electronic component 77 may be electrically connected to a control line laid on the first substrate 711 and used for or controlling the operation of the laser projection module 100 or the light receiver 200. The electronic component 77 is housed in the receiving cavity 723, and the space in the pad 72 is used reasonably. It is not necessary to increase the width of the first substrate 711 to set the electronic component 77, which is beneficial to reducing the overall size of the depth image acquisition device 300. The number of the receiving cavities 723 may be one or more, and the receiving cavities 723 may be spaced apart from each other. When mounting the pad 72, the receiving cavity 723 and the electronic component 77 may be aligned and the pad 72 may be disposed on the first substrate 711.

Please continue to refer to FIG. 2 to FIG. 5. In some embodiments, the cushion block 72 is provided with an escape through hole 724 connected to at least one receiving cavity 723, and at least one electronic component 77 extends into the escape through hole 724. It can be understood that when the electronic component 77 needs to be accommodated in the avoiding through hole, the height of the electronic component 77 is required to be not higher than the height of the receiving cavity 723. For electronic components having a height higher than the receiving cavity 723, an avoiding through hole 724 corresponding to the receiving cavity 723 may be provided, and the electronic component 77 may partially extend into the avoiding through hole 724 so as not to increase the height of the cushion 72. Arranges the electronic component 77.

Please also refer to FIGS. 2 to 5. In some embodiments, the first substrate assembly 711 further includes a reinforcing plate 713, and the reinforcing plate 713 is coupled to a side of the first substrate 711 opposite to the pad 72. The reinforcing plate 713 may cover one side of the first substrate 711, and the reinforcing plate 713 may be used to increase the strength of the first substrate 711 and prevent deformation of the first substrate 711. In addition, the reinforcing plate 713 may be made of a conductive material, such as a metal or an alloy. When the depth image acquisition device 300 is installed on the electronic device 800, the reinforcing plate 713 and the housing 801 may be electrically connected to make the reinforcing plate 713. Grounding and effectively reducing the interference of the static electricity of external components on the depth image acquisition device 300.

Please refer to FIG. 2 to FIG. 5 again. In other embodiments, the depth image acquisition device 300 further includes a connector 76 connected to the first substrate assembly 71 and used to electrically communicate with electronic components external to the depth image acquisition device 300. Sexual connection.

Please refer to FIG. 6 and FIG. 8 to FIG. 11 together. The present invention also provides a control method of the laser projection module 100. The laser projection module 100 is the laser projection module 100 according to any one of the above embodiments. Control methods include:

Step 03 includes:

031: determine whether the light detection signal exceeds the preset range; and

Step 03 may also include:

The control method after step 03 further includes:

With reference to FIG. 6 and FIG. 7, step 01, step 03, step 031, step 032, step 033, and step 05 can all be implemented by the processor 65. That is to say, the processor 65 may be configured to obtain a photodetection electrical signal output from the photodetector 63 and determine whether the diffuser 20 is abnormal based on the photodetection signal. Further, the processor 65 may be further configured to determine whether the light detection signal exceeds a preset range, determine that the diffuser 20 is abnormal when the light detection signal exceeds the preset range, and determine whether the diffuser 20 is abnormal according to the light detection signal and the driving current of the light source 10. And controlling the light source 10 to turn off when the diffuser 20 is abnormal.

It can be understood that the light transmittance of the diffuser 20 usually cannot reach 100%. Most of the laser light emitted by the light source 10 will be diffused out by the diffuser 20, but a small part of the laser light will be reflected by the diffuser 20. The light detector 63 can be used for receiving the laser light reflected by the diffuser 20. After receiving the laser light reflected from the diffuser 20, the photodetector 63 forms a photodetection electrical signal output. The processor 65 may receive the light detection electric signal output from the light detector 63 and determine whether the diffuser 20 is abnormal according to the light detection electric signal.

The control method of the laser projection module 100 according to the embodiment of the present invention determines whether the diffuser 20 is abnormal based on the light detection electric signal output from the photodetector 63, so that countermeasures can be taken when the diffuser 20 is abnormal, such as turning off the light source 10, The driving current and the like of the light source 10 are reduced to improve the safety of the user.

In the description of this specification, reference is made to the terms "certain embodiments", "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" The description means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same implementation or example. Moreover, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more implementations or examples.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as “first” and “second” may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, for example, two, three, unless specifically defined otherwise.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on the present invention. Those skilled in the art can interpret the above within the scope of the present invention. The embodiments are subject to change, modification, replacement, and modification, and the scope of the present invention is defined by the claims and their equivalents.

Claims

A laser projection module, characterized in that the laser projection module includes:

A light source for emitting laser light;

A diffuser for diffusing the laser light;

A light detector for receiving the laser light reflected by the diffuser to form a light detection electrical signal; and

A processor configured to determine whether the diffuser is abnormal according to the light detection signal.
The laser projection module according to claim 1, wherein the processor is configured to determine whether the light detection signal exceeds a preset range, and determine the diffusion when the light detection signal exceeds the preset range. Device abnormality.
The laser projection module according to claim 1, wherein the processor is configured to determine whether the diffuser is abnormal according to the light detection signal and a driving current of the light source.
The laser projection module according to claim 1, wherein the processor is further configured to control the light source to be turned off when the diffuser is abnormal.
The laser projection module according to claim 1, wherein the light detector comprises a plurality of light detectors, and the plurality of light detectors are arranged symmetrically around the light source.
A method for controlling a laser projection module, characterized in that the laser projection module includes a light source, a diffuser, and a light detector, the light source is used to emit laser light, the diffuser is used to diffuse the laser light, and the light The detector is configured to receive laser light reflected by the diffuser to form a light detection electrical signal; the control method includes:

Acquiring the light detection electric signal output by the light detector; and

It is determined whether the diffuser is abnormal according to the light detection signal.
The control method according to claim 6, wherein the determining whether the diffuser is abnormal according to the light detection signal comprises:

Determining whether the light detection signal exceeds a preset range; and

It is determined that the diffuser is abnormal when the light detection signal exceeds the preset range.
The control method according to claim 6, wherein the determining whether the diffuser is abnormal according to the light detection signal comprises:

It is determined whether the diffuser is abnormal according to the light detection signal and a driving current of the light source.
The control method according to claim 6, further comprising:

And controlling the light source to be turned off when the diffuser is abnormal.
The control method according to claim 6, wherein the light detector comprises a plurality of light detectors, and the plurality of light detectors are arranged symmetrically around the light source.
A depth image acquisition device, comprising: a laser projection module and a light receiver, wherein the light receiver is configured to receive laser light emitted by the laser projection module;

The laser projection module includes:

A light source for emitting laser light;

A diffuser for diffusing the laser light;

A light detector for receiving the laser light reflected by the diffuser to form a light detection electrical signal; and

A processor configured to determine whether the diffuser is abnormal according to the light detection signal.
The depth image acquisition device according to claim 11, wherein the processor is configured to determine whether the light detection signal exceeds a preset range, and determine the diffusion when the light detection signal exceeds the preset range. Device abnormality.
The depth image acquisition device according to claim 11, wherein the processor is configured to determine whether the diffuser is abnormal according to the light detection signal and a driving current of the light source.
The depth image acquisition device according to claim 11, wherein the processor is further configured to control the light source to be turned off when the diffuser is abnormal.
The depth image acquisition device according to claim 11, wherein the light detector comprises a plurality of light detectors, and the plurality of light detectors are arranged symmetrically around the light source.
An electronic device, comprising: a casing and a depth image acquisition device, the depth image acquisition device being disposed on the casing;

The depth image acquisition device includes a laser projection module and a light receiver, and the light receiver is configured to receive laser light emitted by the laser projection module;

The laser projection module includes:

A light source for emitting laser light;

A diffuser for diffusing the laser light;

A light detector for receiving the laser light reflected by the diffuser to form a light detection electrical signal; and

A processor configured to determine whether the diffuser is abnormal according to the light detection signal.
The electronic device according to claim 16, wherein the processor is configured to determine whether the light detection signal exceeds a preset range, and determine that the diffuser is abnormal when the light detection signal exceeds the preset range. .
The electronic device according to claim 16, wherein the processor is configured to determine whether the diffuser is abnormal according to the light detection signal and a driving current of the light source.
The electronic device according to claim 16, wherein the processor is further configured to control the light source to be turned off when the diffuser is abnormal.
The electronic device according to claim 16, wherein the light detector comprises a plurality of light detectors, and the plurality of light detectors are arranged symmetrically around the light source.