WO2021026829A1

WO2021026829A1 - Light transmitting module, light receiving module, depth camera, and electronic device

Info

Publication number: WO2021026829A1
Application number: PCT/CN2019/100633
Authority: WO
Inventors: 刘福
Original assignee: Oppo广东移动通信有限公司
Priority date: 2019-08-14
Filing date: 2019-08-14
Publication date: 2021-02-18
Also published as: CN114096884A

Abstract

A light transmitting module (30), a light receiving module (40), a depth camera (100), and an electronic device (1000). The light transmitting module (30) comprises a light source (31) and a diffuser (33). The light source (31) is configured to transmit a light signal, the wavelength of the light signal being 1350 nm-1550 nm. The diffuser (33) is configured to diffuse the light signal.

Description

Light emitting module, light receiving module, depth camera and electronic equipment

Technical field

This application relates to the field of three-dimensional imaging technology, in particular to a light emitting module, a light receiving module, a depth camera and an electronic device.

Background technique

Time of Flight (TOF) depth cameras have been widely used in electronic devices such as mobile phones, so that the electronic devices have the function of acquiring three-dimensional information of objects. The time-of-flight depth camera can calculate the depth information of the measured object by calculating the time difference between the time when the light emitting module emits the light signal and the time when the light receiving module receives the light signal.

Summary of the invention

The embodiments of the present application provide a light emitting module, a light receiving module, a depth camera, and electronic equipment.

The light emitting module of the embodiment of the present application includes a light source and a diffuser. The light source is used to emit an optical signal, and the wavelength of the optical signal is 1350 nm to 1550 nm. The diffuser is used to diffuse the optical signal.

The light receiving module of the embodiment of the present application includes a lens assembly and a photosensitive element. The photosensitive element is used to receive only the optical signal passing through the lens assembly and having a wavelength range of 1350 nm to 1550 nm.

The depth camera of the embodiment of the present application includes a light emitting module and a light receiving module. The light emitting module includes a light source and a diffuser. The light source is used to emit an optical signal, and the wavelength of the optical signal is 1350 nm to 1550 nm. The diffuser is used to diffuse the optical signal. The light receiving module includes a lens assembly and a photosensitive element. The photosensitive element is used to receive only the optical signal passing through the lens assembly and having a wavelength range of 1350 nm to 1550 nm.

The electronic device of the embodiment of the present application includes a casing and a depth camera. The depth camera includes a light emitting module and a light receiving module. The light emitting module includes a light source and a diffuser. The light source is used to emit an optical signal, and the wavelength of the optical signal is 1350 nm to 1550 nm. The diffuser is used to diffuse the optical signal. The light receiving module includes a lens assembly and a photosensitive element. The photosensitive element is used to receive only the optical signal passing through the lens assembly and having a wavelength range of 1350 nm to 1550 nm.

The light emitting module, light receiving module, depth camera, and electronic device of the embodiments of the present application use a light source that can emit light signals with a wavelength of 1350 nm to 1550 nm, and a photosensitive element that can only receive light signals with a wavelength of 1350 nm to 1550 nm. Since there is almost no background light signal with a wavelength of 1350nm-1550nm in the ambient light, the influence of the background light signal on the calculation of the moment when the light receiving module receives the light signal is avoided, and the acquisition accuracy of depth information can be further improved.

The additional aspects and advantages of the embodiments of the present application will be partially given in the following description, and some will become obvious from the following description, or be understood through the practice of the present application.

Description of the drawings

The above-mentioned and/or additional aspects and advantages of the present application will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, in which:

FIG. 1 is a schematic diagram of a plan structure of an electronic device according to an embodiment of the present application;

2 is a schematic diagram of a three-dimensional assembly of a depth camera according to an embodiment of the present application;

3 is a schematic diagram of a plane assembly of a depth camera according to an embodiment of the present application;

4 is a schematic cross-sectional view of the depth camera shown in FIG. 3 along the line IV-IV;

5 is a schematic diagram of a plane assembly of a depth camera according to an embodiment of the present application;

6 and 7 are three-dimensional exploded schematic diagrams of the depth camera according to the embodiment of the present application;

8 and 9 are three-dimensional exploded schematic diagrams of the cushion assembly and the light emitting module of the depth camera according to the embodiment of the present application;

FIG. 10 is a schematic diagram of a planar structure of a light receiving module according to some embodiments of the present application;

FIG. 11 is a schematic structural diagram of a diffuser of a light receiving module according to some embodiments of the present application;

FIG. 12 is a schematic diagram of the power of the optical signal output by the light emitting module according to some embodiments of the present application.

Description of main components and symbols:

Electronic device 1000, case 200, front 201, back 202, visible light camera 300, display 400, depth camera 100, substrate 10, flexible circuit board 11, reinforcing plate 12, spacer component 20, spacer 21, first Surface 211, second surface 212, conductive hole 213, thermal hole 214, conductive member 22, heat conductive member 23, light emitting module 30, light source 31, bracket 32, installation space 321, light outlet 322, diffuser 33, light incident Surface 331, light-emitting surface 332, non-coated area 333, coated area 334, light detector 34, glue 35, high reflective film 36, filter film 37, light receiving module 40, lens barrel 41, light entrance 411, photosensitive Element 42, lens assembly 43, filter 44, housing 50, first housing cavity 51, second housing cavity 52, mounting groove 53, first sub-housing 54, light opening 541, second sub-housing 55 , Connector 60, Processor 70.

detailed description

The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The following embodiments described with reference to the accompanying drawings are exemplary, and are only used to explain the present application, and cannot be understood as a limitation to the present application.

In this application, unless expressly stipulated and defined otherwise, the “on” or “under” of the first feature on the second feature may be in direct contact with the first and second features, or indirectly through an intermediary. contact. Moreover, the "above", "above" and "above" of the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or it only means that the level of the first feature is higher than the second feature. The “below”, “below” and “below” of the second feature of the first feature may mean that the first feature is directly below or obliquely below the second feature, or it simply means that the level of the first feature is smaller than the second feature.

Please refer to FIG. 3 and FIG. 4, this application provides a light emitting module 30. The light emitting module 30 includes a light source 31 and a diffuser 33. The light source 31 is used to emit an optical signal, wherein the wavelength of the optical signal is 1350 nm to 1550 nm. The diffuser 33 is used to diffuse the light signal emitted by the light source 31.

Please continue to refer to FIG. 3 and FIG. 4, this application also provides a light receiving module 40. The light receiving module 40 includes a lens assembly 43 and a photosensitive element 42. The photosensitive element 42 is used for receiving only the optical signal passing through the lens assembly 43 and having a wavelength range of 1350 nm to 1550 nm.

Please also refer to FIG. 3 and FIG. 4, this application also provides a depth camera 100. The depth camera 100 includes a light emitting module 30 and a light receiving module 40. The light emitting module 30 includes a light source 31 and a diffuser 33. The light source 31 is used to emit an optical signal, wherein the wavelength of the optical signal is 1350 nm to 1550 nm. The diffuser 33 is used to diffuse the light signal emitted by the light source 31. The light receiving module 40 includes a lens assembly 43 and a photosensitive element 42. The photosensitive element 42 is used for receiving only the optical signal passing through the lens assembly 43 and having a wavelength range of 1350 nm to 1550 nm.

Referring to FIG. 1 and FIG. 4, the present application also provides an electronic device 1000. The electronic device 1000 includes a housing 200 and a depth camera 100. The depth camera 100 includes a light emitting module 30 and a light receiving module 40. The light emitting module 30 includes a light source 31 and a diffuser 33. The light source 31 is used to emit an optical signal, wherein the wavelength of the optical signal is 1350 nm to 1550 nm. The diffuser 33 is used to diffuse the light signal emitted by the light source 31. The light receiving module 40 includes a lens assembly 43 and a photosensitive element 42. The photosensitive element 42 is used for receiving only the optical signal passing through the lens assembly 43 and having a wavelength range of 1350 nm to 1550 nm.

In a depth camera that acquires depth information of a measured object based on Time of Flight (TOF) technology, the wavelength band of the light signal emitted by the light emitting module is usually 850 nm or 940 nm. In the ambient light, there are more light with wavelengths of 850nm or 940nm. When the depth camera is working in an outdoor environment, in addition to receiving the light signal emitted by the light emitting module, the light receiving module will also receive light with a wavelength of 850nm or 940nm in the ambient light (ie, background light signal). This part of the background light signal will affect the calculation of the time when the light receiving module receives the light signal, and an error in the calculation of the time when the light receiving module receives the light signal will affect the accuracy of depth information acquisition.

The light emitting module 30, the light receiving module 40, the depth camera 100, and the electronic device 1000 of the embodiment of the present application use a light source 31 that can emit light signals with a wavelength of 1350 nm to 1550 nm, and use light sources that can only receive light with a wavelength of 1350 nm to 1550 nm. Signal photosensitive element 42. Since there is almost no light with a wavelength of 1350nm～1550nm (ie, background light signal) in the ambient light, even in an outdoor strong light environment, the background light signal with a wavelength of 1350nm～1550nm is very small, and a very small amount of background light The signal has little effect on the calculation of the time when the light receiving module 40 receives the light signal, and the depth information calculated based on the more accurate time when the light receiving module 40 receives the light signal has a higher accuracy. It should be noted that: the optical signal with a wavelength band of 1350nm-1550nm means that the wavelength of the optical signal can be 1350nm, 1360nm, 1370nm, 1385nm, 1394nm, 1400nm, 1410nm, 1425nm, 1450nm, 1480nm, 1490nm, 1500nm, 1520nm, 1535nm, Any one of 1540nm, 1550nm and any value between any two values.

Please refer to FIG. 1, the electronic device 1000 of the embodiment of the present application includes a casing 200 and a depth camera 100. The electronic device 1000 can be a mobile phone, a tablet computer, a smart watch, a smart bracelet, a smart helmet, a smart glasses, a head-mounted display device, a game console, a notebook computer, etc. This application uses the electronic device 1000 as a mobile phone as an example for description. The specific form of the electronic device 1000 is not limited to a mobile phone.

The case 200 can be used as a mounting carrier for the functional elements of the electronic device 1000. The case 200 can provide protection against dust, water, and drop resistance for the functional elements. The functional elements can be the display screen 400 of the electronic device 1000, the visible light camera 300, Depth camera 100, motherboard, power module and other components. The casing 200 may include a front 201 and a back 202, the front 201 and the back 202 are opposite to each other, and functional elements may be installed on the front 201 or the back 202. For example, in the example shown in FIG. 1, the display screen 400 is installed on the front 201, the visible light camera 300 is installed on the back 202, and the depth camera 100 is installed on the back 202. At this time, the visible light camera 300 can be used as a rear camera, and the depth camera 100 It can also be used as a rear depth camera. Among them, the visible light camera 300 may include one or more of a telephoto camera, a wide-angle camera, a periscope camera, a black-and-white camera, etc.; the display screen 400 may be a display screen 400 such as a liquid crystal display, an OLED display, or a Microled display. .

Of course, in other embodiments, the installation positions of the display screen 400, the visible light camera 300, and the depth camera 100 on the housing 200 can be arranged in other ways. For example, the display screen 400 can be set on the front 201 and the back 202 at the same time, and the visible light camera 300 can also be installed on the front 201 as a front camera, and the depth camera 100 can also be installed on the front 201 as a front depth camera. In addition, the visible light camera 300 can also be installed below the display screen 400, that is, a visible light camera. 300 receives light passing through the display screen 400 for imaging. The depth camera 100 can also be arranged under the display screen 400. The light signal emitted by the depth camera 100 enters the outside of the electronic device 1000 after passing through the display screen 400, and the depth camera 100 receives The light signal after passing through the display screen 400 from the outside of the electronic device 1000 obtains depth information.

1 to 4, the depth camera 100 includes a substrate 10, a housing 50, a spacer assembly 20, a light emitting module 30, a light receiving module 40, and a processor 70. Wherein, the depth camera 100 may be a time-of-flight depth camera that uses the principle of time-of-flight ranging to obtain depth information.

Please refer to FIGS. 2 to 4, the substrate 10 can be used to carry the housing 50, the spacer assembly 20, the light emitting module 30 and the light receiving module 40. The substrate 10 can be used to electrically connect the main board of the electronic device 1000 with the spacer assembly 20, the light emitting module 30 and the light receiving module 40. The substrate 10 includes a flexible circuit board 11 and a reinforcement board 12. A circuit is laid on the flexible circuit board 11. The spacer assembly 20 and the light receiving module 40 can be arranged on one side of the flexible circuit board 11. The circuit and the spacer assembly 20, the light emitting module 30 and the light receiving module 40 are all Electrical connection. The reinforcing plate 12 can be arranged on the other side of the flexible circuit board 11, and the reinforcing plate 12 can be made of a material with greater hardness such as steel, so as to improve the overall strength of the substrate 10 and facilitate the assembly of the circuit and the spacer. 20 and the light receiving module 40 are electrically connected.

3 and 4, the housing 50 is disposed on the substrate 10, and the housing 50 can be connected to the substrate 10, for example, the housing 50 is bonded to the substrate 10 by glue. The housing 50 may be used to form a part of the housing of the depth camera 100, and the cushion assembly 20, the light emitting module 30 and the light receiving module 40 may be at least partially housed in the housing 50.

The housing 50 may be an integrally formed whole. The housing 50 may be provided with a plurality of cavities, and different cavities may be used to accommodate different components in the aforementioned cushion assembly 20, the light emitting module 30, and the light receiving module 40. The housing 50 and the substrate 10 enclose a first accommodating cavity 51 and a second accommodating cavity 52. The first accommodating cavity 51 may be spaced from the second accommodating cavity 52, and the first accommodating cavity 51 may also communicate with the second accommodating cavity 52.

In the embodiment of the present application, the housing 50 includes a first sub-housing 54 and a second sub-housing 55. The first sub-housing 54 and the second sub-housing 55 can be manufactured by an integral molding process, for example, The first sub-housing 54 and the second sub-housing 55 are formed by a single casting, or the first and the

second sub-housing

54 and 55 are formed by a single cutting process. The first sub-housing 54 and the substrate 10 jointly enclose a first accommodating cavity 51, the first sub-housing 54 is formed with a light-passing port 541, the light-passing port 541 communicates with the first accommodating cavity 51, and the second sub-housing 55 and The substrate 10 collectively encloses a second receiving cavity 52.

In another example, the housing 50 includes a plurality of separate sub-housings, and each of the sub-housings can be individually connected to the substrate 10, for example, one sub-housing is used to house the light emitting module 30 and the other sub-housing. For accommodating the light receiving module 40, the two sub-shells can be glued on the substrate 10 respectively. When one of the components (which can be the light emitting module 30 or the light receiving module 40) needs to be repaired or replaced, Disassemble one of the sub-housings without affecting the other sub-housing and other components.

Please refer to FIG. 4, FIG. 8 and FIG. 9, the spacer assembly 20 is disposed on the substrate 10. The spacer assembly 20 is electrically connected to the substrate 10. The spacer assembly 20 includes a spacer 21 and a conductive element 22.

The spacer 21 is disposed on the substrate 10, and the relative position of the spacer 21 and the substrate 10 may be fixed, for example, the spacer 21 is bonded to the substrate 10. The cushion block 21 may be accommodated in the first accommodating cavity 51 to prevent the cushion block 21 from falling off the substrate 10 and falling out. Of course, the cushion block 21 may not be accommodated in the housing 50. The spacer 21 may be insulated, for example, the spacer 21 may be a PCB board, a ceramic block, or the like. The spacer 21 includes a first surface 211 and a second surface 212, wherein the first surface 211 and the second surface 212 are opposite to each other. When the spacer 21 is arranged on the substrate 10, the first surface 211 is carried on the substrate 10, and the second surface 212 forms a certain height difference with the substrate 10, so that the components arranged on the second surface 212 are different from those directly arranged on the substrate 10. Compared with the components, the components arranged on the second surface 212 are padded with respect to the substrate 10. By selecting the spacers 21 of different heights, the height arrangement requirements of different components can be adapted. A conductive hole 213 is defined in the spacer 21, and the conductive hole 213 penetrates the first surface 211 and the second surface 212. The conductive hole 213 can be opened at a position spaced from the outer peripheral wall of the spacer block 21, and the conductive hole 213 can also be opened on the outer peripheral wall of the spacer block 21.

The conductive member 22 is disposed in the conductive hole 213. The conductive member 22 may be any conductive material such as conductive silver paste, conductive ceramic, etc. The conductive member 22 may be filled in the conductive hole 213 and exposed from the first surface 211 and the second surface 212. The part of the conductive member 22 exposed from the first surface 211 can be used to electrically connect with the substrate 10, and the part of the conductive member 22 exposed from the second surface 212 can be used to communicate with elements (such as a light source) provided on the second surface 212. 31 and/or the photodetector 34) are electrically connected, so that the conductive member 22 is used to electrically connect the element and the substrate 10. According to the wiring requirements of the components arranged on the second surface 212, the number of conductive holes 213 and the positions of the conductive holes 213 can be set arbitrarily, and are not limited to the examples in the embodiments shown in the drawings of this application.

2 and 4, the light emitting module 30 is disposed on the second surface 212, the light emitting module 30 is electrically connected to the substrate 10 through the conductive member 22, and the light receiving module 40 is disposed on the substrate 10. It can be understood that since the first surface 211 is combined with the substrate 10 and the light receiving module 40 is disposed on the substrate 10, the height of the light receiving module 40 and the first surface 211 relative to the substrate 10 is basically the same, while the second pad The block 21 has a certain thickness, that is, the second surface 212 and the first surface 211 have a certain height difference. Therefore, the installation height of the light emitting module 30 (relative to the substrate 10, the same below) is higher than that of the light receiving module 40 Set the height (relative to the substrate 10, the same below). Since the height of the light emitting module 30 is smaller than the height of the light receiving module 40, the height of the light emitting module 30 is higher than that of the light receiving module 40, which can prevent the light receiving module 40 from blocking the light emitting The module 30 emits a light signal, so that the light emitting end of the light emitting module 30 is closer to the light incident end of the light receiving module 40, so that the depth information obtained by the depth camera 100 is relatively complete.

Please refer to FIG. 4 and FIG. 8 to FIG. 10, the light emitting module 30 is disposed on the second surface 212. In the embodiment of the present application, both the light emitting module 30 and the cushion block 21 are accommodated in the first receiving cavity 51. The light emitting module 30 includes a light source 31, a bracket 32, a diffuser 33 (diffuser), a light detector 34, a high reflection film 36, and a filter film 37.

The bracket 32 is disposed on the second surface 212. The bracket 32 may be adhered to the second surface 212 by glue 35. The bracket 32 and the second surface 212 jointly enclose an installation space 321, and the installation space 321 can be used for installing the light source 31. The bracket 32 may also be provided with a light outlet 322, the light outlet 322 communicates with the installation space 321, and the light outlet 322 can be used for light emitted by the light source 31 to pass through.

The light source 31 is contained in the installation space 321, and the light source 31 may be a vertical cavity surface emitting laser (VCSEL) or an edge emitting laser (EEL). The light source 31 can send out a light signal with a uniform light spot, and the wavelength of the light signal is 1350 nm to 1550 nm, and the light signal can reach the diffuser 33 after passing through the light exit 322. The light source 31 can be arranged on the second surface 212, the light source 31 can be electrically connected to the conductive member 22, and the light source 31 is electrically connected to the substrate 10 through the conductive member 22, so as to avoid using too long or too complicated connection lines to connect the light source 31 and The substrate 10 reduces the parasitic inductance of the connection line, which is beneficial for the light source 31 to output an ideal optical signal, and improves the accuracy of the depth information finally obtained. In one example, the pins of the light source 31 may be directly electrically connected to the conductive member 22 exposed from the second surface 212. In another example, the light source 31 and the conductive member 22 may be electrically connected by wire bonding. connection.

The diffuser 33 is disposed on the bracket 32. Specifically, the diffuser 33 may be bonded to the bracket 32 by glue 35. The diffuser 33 includes a light incident surface 331 and a light output surface 332 opposite to each other, and the light incident surface 331 is opposite to the light source 31. The diffuser 33 may be made of materials such as transparent glass or resin. The diffuser 33 may be located outside the installation space 321. For example, the diffuser 33 may completely cover the light outlet 322, and the light incident surface 331 of the diffuser 33 may conflict with the bracket 32. The light signal emitted from the light source 31 passes through the light outlet 322 and then reaches the diffuser 33. The diffuser 33 can increase the viewing angle range of the light signal, so that the light signal emitted by the light emitting module 30 illuminates a larger range. The light signal passing through the diffuser 33 may further pass through the light opening 541, and after passing through the light opening 541, the light signal exits the depth camera 100.

It should be mentioned that if a hole needs to be opened on the casing 200 for the light signal emitted by the light emitting module 30 to pass through, the light emitting module 30 is heightened to reduce the light emitting module 30 and the casing. The distance between the openings on the 200. Since the light signal emitted by the light emitting module 30 is a divergent light signal, the distance between the light emitting module 30 and the opening on the casing 200 is the same under the premise that the luminous flux of the emitted light is the same The smaller the size, the smaller the size of the opening, and the smaller the opening. On the one hand, the impact on the appearance of the electronic device 1000 is smaller, and on the other hand, the screen-to-body ratio of the electronic device 1000 can be enlarged.

The light detector 34 is disposed on the second surface 212 and located in the installation space 321. The conductive hole 213 is used for allowing the conductive member 22 to pass through to electrically connect the photodetector 34 and the substrate 10. The number of photodetectors 34 can be one or more. When the number of photodetectors 34 is one, one photodetector 34 corresponds to one conductive hole 213; when the number of photodetectors 34 is more than one, each photodetector 34 corresponds to a conductive hole 213. The light detector 34 can be used to receive the light signal reflected by the diffuser 33 to form a detection electrical signal. The detection electrical signal can be a current signal, a voltage signal, a power signal calculated from a current signal or a voltage signal, a resistance signal, etc., There is no restriction here. The detected electrical signal can be used as a basis for determining whether the light source 31 is in a constant power working state, or as a basis for determining whether the diffuser 33 is in a normal working state, or as a basis for determining whether the light source 31 is in a constant power working state. The basis for determining whether the diffuser 33 is in a normal working state. Where the light source 31 is in a constant power working state, it means that the output power of the light source 31 is stable at a target power (the target power can be a value or a range. When the target power is a value, the power output by the light source 31 is equal to Target power, when the target power is within a power range, the power output by the light source 31 is within the power range). If the power output by the light source 31 is not stabilized at a target power, the light source 31 is not in a constant power working state. Of course, different application scenarios may have different requirements for the output power of the light source 31. For example, some application scenarios (such as the application scenario where the depth camera 100 is used as a rear depth camera) require the output power of the light source 31 to stabilize at a higher power ( A value or a range), for example, the output power of the light source 31 is required to stabilize at 10W. Some application scenarios (such as the application scenario where the depth camera 100 is used as a front depth camera) require that the output power of the light source 31 be stabilized at a lower power (a value or a range), for example, the output power of the light source 31 is required to be stabilized at 5W -6W. Among them, for different application scenarios, the target power may be inconsistent. When the diffuser 33 is in a normal working state, it means that the diffuser 33 is not damaged (such as ruptured) nor detached. When the diffuser 33 is damaged and/or detached, the diffuser 33 is in an abnormal working state.

Specifically, when the light source 31 is in a constant power working state and the diffuser 33 is in a normal working state, the light source 31 outputs a light signal with stable power, the diffuser 33 is intact, and the light detector 34 can receive all the reflected light from the diffuser 33. For the optical signal, the detected electrical signal output by the photodetector 34 will be equal to the first electrical signal (ie a value) or be within the range of the first electrical signal. Since different application scenarios have different requirements for the output power of the light source 31, the first electrical signal (or the first electrical signal range) is determined according to the target power in different application scenarios. When the target power is larger, the first electrical signal The signal (or the value in the first electrical signal range) is also larger; when the target power is smaller, the first electrical signal (or the value in the first electrical signal range) is also smaller. When the light source 31 is not in a constant power working state and the diffuser 33 is in a normal working state, the detection electrical signal will be equal to the second electrical signal (ie a value) or within the range of the second electrical signal, wherein, when the detection electrical signal is equal to the first For the second electrical signal, the second electrical signal is smaller than the first electrical signal or smaller than the minimum value of the first electrical signal range; when the detection electrical signal is within the second electrical signal range, the maximum value of the second electrical signal range is less than the first electrical signal The signal may be less than the minimum value of the first electrical signal range. The light source 31 is not in a constant power working state may be caused by the temperature change of the light source 31. Generally, when the temperature of the light source 31 increases, the output power of the light source 31 cannot be stabilized at the target power required by the current application scenario. The output power will be reduced, the amount of the light signal reflected by the diffuser 33 received by the photodetector 34 will be reduced, and the output detection electrical signal will also be reduced. When the diffuser 33 is not in a normal working state, no matter whether the light source 31 is in a constant power working state, the detection electrical signal will be equal to the third electrical signal (ie a value) or within the range of the third electrical signal. When the detected electrical signal is equal to the third electrical signal, the third electrical signal is less than the second electrical signal or less than the minimum value of the second electrical signal range; when the detected electrical signal is within the third electrical signal range, the third electrical signal range is the largest The value is smaller than the second electrical signal or smaller than the minimum value of the second electrical signal range. It can be understood that when the diffuser 33 is damaged and/or falls off, regardless of whether the power of the optical signal output by the light source 31 is stable at the target power, the optical signal reflected by the diffuser 33 will be greatly reduced, and the photodetector 34 can receive The reflected light signal is also greatly reduced, and the output detection electrical signal will be greatly reduced.

Referring to FIG. 10 and FIG. 11, the high reflection film 36 is provided on the diffuser 33. The diffuser 33 includes a coating area 334 and a non-coating area 333 connected to the coating area 334. The highly reflective film 36 is formed in the coating area 334, and the coating area 334 corresponds to the light receiving area of the photodetector 34; the non-coating area 334 corresponds to the optical signal area where the light source 31 emits optical signals. When the number of photodetectors 34 is one, the coating area 334 corresponds to the light-receiving area of one photodetector 34; when the number of photodetectors 34 is multiple, the coating area 334 and the light-receiving area of multiple photodetectors 34 The light area corresponds, for example, the coated area 334 may surround the non-coated area 333, so that the coated area 334 can correspond to the light-receiving areas of the multiple photodetectors 34. The highly reflective film 36 is used to reflect light signals with a wavelength of 1350 to 1550 nm. It can be understood that when the intensity of the outdoor ambient light is strong, there may be a small amount of 1350-1550nm light in the ambient light. This part of the light may pass through the diffuser 33 and be incident on the light detector 34, then the light detector 34 In addition to receiving the light signal reflected back by the diffuser 33, it is also possible to receive light of 1350 to 1550 nm in the ambient light. The high reflection film 36 has high reflectivity. The high reflection film 36 is used to reflect the light of 1350 to 1550 nm in the ambient light, which can prevent the light of 1350 to 1550 nm in the ambient light from interfering with the photodetector 34.

The filter film 37 is provided on the light detector 34. When the number of photodetectors 34 is one, there is also one filter film 37, and the one filter film 37 is arranged on the one photodetector 34; when the number of photodetectors 34 is more than one, the filter There are also multiple light films 37, and each light detector 34 is provided with a filter film 37. The filter film 37 can be used to transmit only light signals with a wavelength of 1350 nm to 1550 nm. It can be understood that although the highly reflective film 36 is provided, light with a wavelength outside of 1350 nm to 1550 nm in the ambient light may pass through the diffuser 33 and be incident on the photodetector 34. A filter film 37 is provided on the photodetector 34, which can block the ambient light with wavelengths other than 1350nm-1550nm from being incident on the photodetector 34, and the photodetector 34 can only receive the light signal reflected by the diffuser 33 In order to output the detection electrical signal, the accuracy of the detection electrical signal is higher, and the working state of the light source 31 and/or the working state of the diffuser 33 determined based on the more accurate detection electrical signal is more accurate.

Please refer to Figure 2, Figure 4, Figure 6 and Figure 7, the light receiving module 40 is arranged on the substrate 10, the light receiving module 40 is formed with a light entrance 411, external light signals enter through the light entrance 411 Light receiving module 40. In the embodiment of the present application, the plane forming the light opening 541 can be flush with the plane forming the light entrance 411, so that the light signal entering the outside through the light opening 541 will not be blocked by the light receiving module 40, and from The light signal passing through the light entrance 411 from outside will not be blocked by the light emitting module 30.

The light receiving module 40 and the light emitting module 30 are disposed on the same substrate 10, so that the positions of the light receiving module 40 and the light emitting module 30 are relatively fixed, and there is no need to use additional brackets for the light receiving module 40 and the light The transmitting module 30 is fixed. When the depth camera 100 is installed, the depth camera 100 can be installed in the housing 200 as a whole, without the need to separately install the light receiving module 40 and the light emitting module 30 before performing calibration. In addition, the depth camera 100 may further include a connector 60 connected to the substrate 10, and the connector 60 is electrically connected to the main board of the electronic device 1000. The number of the connector 60 can be a single one, and a single connector 60 can be electrically connected to the light emitting module 30 and the light receiving module 40 at the same time through wire routing, and there is no need to provide multiple connectors 60. The light receiving module 40 includes a photosensitive element 42, a filter 44, a lens barrel 41 and a lens assembly 43.

The photosensitive element 42 may be disposed on the substrate 10 and electrically connected to the substrate 10, and the photosensitive element 42 is accommodated in the second receiving cavity 52. The photosensitive element 42 is used for receiving only the optical signal passing through the lens assembly 43 and having a wavelength range of 1350 nm to 1550 nm. The material of the photosensitive element 42 may include silicon and germanium, wherein the proportion of germanium is less than or equal to 10%, for example, the proportion of germanium may be 0.1%, 1%, 2.5%, 3.8%, 5%, 7%, 8. %, 9%, 10%, etc. The material of the photosensitive element 42 may also include silicon and indium gallium arsenide. It can be understood that the photosensitive element made of silicon can only respond to light signals in the wavelength range of 350nm-1064nm, and cannot respond to light signals in the wavelength range of 1350nm to 1550nm, while the photosensitive element 42 made of silicon and germanium is either made of silicon and indium gallium The photosensitive element 42 made of arsenic can respond to light signals with longer wavelengths, such as 1350 nm to 1550 nm. Therefore, the photosensitive element 42 can be made of silicon and germanium or the photosensitive element 42 can be made of silicon and indium gallium arsenide. After the photosensitive element 42 receives the optical signal, the photosensitive element 42 converts the optical signal into an electrical signal, and the electrical signal can be used for calculating depth information.

The filter 44 is disposed above the photosensitive element 42 and is received in the second receiving cavity 52. The filter 44 is used to only transmit light signals with a wavelength of 1350 nm to 1550 nm, so the photosensitive element 42 can only receive light signals with a wavelength of 1350 nm to 1550 nm. The lens assembly 43 may be installed in the lens barrel 41. The lens assembly 43 may be composed of multiple (for example, 4) lenses. The aforementioned light entrance 411 is opened on the lens barrel 41. After the optical signal enters from the light entrance 411, it first passes through the lens assembly 43 and is incident on the filter 44. The filter 44 filters out the optical signals with wavelengths outside of 1350nm-1550nm, and finally only the optical signals with 1350nm-1550nm It can be focused on the photosensitive element 42. The lens barrel 41 may be detachably installed with the housing 50, specifically, the lens barrel 41 may be detachably installed with the second sub-housing 55. In the embodiment of the present application, the housing 50 is further provided with an installation groove 53, and the installation groove 53 can be used for installing the lens barrel 41. The position of the installation groove 53 may correspond to the position of the second receiving cavity 52. The outer wall of the lens barrel 41 is formed with an external thread, and the inner wall of the installation groove 53 is formed with an internal thread. The lens barrel 41 and the housing 50 are detachably connected with the external thread and the internal thread. For example, the lens barrel 41 is screwed into the installation groove 53. Or the lens barrel 41 is screwed out of the installation groove 53.

When installing the depth camera 100, the spacer assembly 20 and the photosensitive element 42 can be fixed on the substrate 10 first, and at the same time the conductive member 22 and the substrate 10, and the photosensitive element 42 and the substrate 10 are electrically connected; then the light emitting module 30 is installed On the second surface 212 of the cushion block 21, the light source 31 and the conductive member 22 are electrically connected at the same time; then the housing 50 is fixed on the substrate 10, so that the light emitting module 30 and the cushion block assembly 20 are received in the first receiving cavity 51 Inside, the photosensitive element 42 is accommodated in the second receiving cavity 52; finally, the lens barrel 41 with the lens assembly 43 can be screwed into the mounting groove 53 to complete the assembly of the entire depth camera 100. Of course, the lens barrel 41 with the lens assembly 43 can also be screwed into the mounting groove 53 first, and then the housing 50 with the lens barrel 41 is fixed on the substrate 10. When necessary (for example, when replacing the lens assembly 43), the lens barrel 41 can be separated from the housing 50 separately, without the need to separate the housing 50 from the substrate 10 first.

Referring to FIGS. 1, 4 and 6, the processor 70 may be provided outside the depth camera 100, for example, on the main board of the electronic device 1000 and electrically connected to the connector 60 of the depth camera 100. The processor 70 may also be arranged in the depth camera 100, for example, in the light emitting module 30 or in the light receiving module 40. The processor 70 may calculate the depth information according to the time when the light transmitting module 30 transmits the light signal and the time when the light receiving module 40 receives the light signal. The processor 70 may also receive the detection electrical signal output by the photodetector 34, and determine whether the light source 31 is in a constant power working state and/or whether the diffuser 33 is in a normal working state according to the detection electrical signal. The specific determination process is as described above , I won’t repeat it here. The processor 70 may also control the light source 31 according to whether the light source 31 is in a constant power working state and/or whether the diffuser 33 is in a normal working state.

Specifically, when the detected electrical signal is equal to the first electrical signal or is within the range of the first electrical signal, the processor 70 is used to control the driving circuit for driving the light source 31 to emit light and still drive the light source 31 to emit light with the current operating current.

When the detected electrical signal is equal to the second electrical signal or within the range of the second electrical signal, the processor 70 may control the driving circuit to increase the operating current to drive the light source 31 to emit light, so that the power output by the light source 31 is maintained at the target power. In an example, the value of the increased operating current can be selected with the help of a temperature detector. Specifically, the light emitting module 30 may also include a temperature detector (not shown), and the temperature detector may be arranged on the second surface 212 Above and adjacent to the light source 31, a temperature detector is used to detect the temperature of the light source 31. When the detected electrical signal is equal to the second electrical signal or within the range of the second electrical signal, the processor 70 controls the temperature detector to detect the temperature of the light source 31, and the processor 70 then changes the operating current-power-temperature curve based on the temperature and the target power. (Different temperatures correspond to different operating current-power curves) find the target operating current, and at the current temperature of the light source 31, the power corresponding to the target operating current is at the target power. The processor 70 may control the driving circuit to drive the light source 31 to emit light with a target operating current, so that the light source 31 outputs an optical signal with a constant power. After the processor 70 controls the drive circuit to drive the light source 31 to emit light with the increased target operating current, the photodetector 34 can continue to receive the light reflected by the diffuser 33 and output a detection electrical signal. At this time, if the electrical signal is detected Equal to the first electrical signal or within the range of the first electrical signal, the processor 70 continues to control the drive circuit to drive the light source 31 to emit light with the increased target operating current; if the detected electrical signal is equal to the second electrical signal or is within the second range , The processor 70 again controls the temperature detector to detect the temperature of the light source 31, and updates the target operating current according to the temperature (the updated target operating current is higher than the target operating current before the update), and the processor 70 controls the updated target operating current The current drives the light source 31 to emit light. In this cycle, the processor 70 gradually increases the operating current for driving the light source 31 to emit light according to the feedback of the photodetector 34, so that the software design ensures that the light source 31 can always output a light signal with a constant power, realizing automatic power control of the light emitting module 30 (Automatic Power Control, APC) adjustment function (shown in Figure 12).

When the detected electrical signal is within the range of the third electrical signal, it indicates that the diffuser 33 is not in a normal working state, that is, the diffuser 33 is damaged or falls off. At this time, the processor 70 can control the driving circuit to stop supplying operating current to the light source 31 to turn off Light source 31. It can be understood that when the diffuser 33 is damaged or falls off, the diffuser 33 cannot diffuse the light signal emitted by the light source 31 into a uniform surface light, which will cause the depth camera 100 to fail to be used normally. When the diffuser 33 is damaged or falls off, the processor 70 turns off the light source 31 to prevent the depth camera 100 from continuously emitting light signals when it cannot be used normally, thereby saving energy consumption of the electronic device 1000.

In summary, in the light emitting module 30, the light receiving module 40, the depth camera 100, and the electronic device 1000 of the embodiment of the present application, the light emitting module 30 emits light signals with a wavelength of 1350 nm to 1550 nm, and the light receiving module 40 receives a wavelength It is an optical signal from 1350nm to 1550nm, and there is almost no background light signal with a wavelength of 1350nm to 1550nm in the ambient light, thereby avoiding the influence of the background light signal on the calculation of the time when the light receiving module 40 receives the optical signal, and further improving the depth information The acquisition accuracy. In addition, light signals with longer wavelengths have lower energy, and according to the characteristics of the human eye, light signals with longer wavelengths will not converge on the retina. Therefore, the use of light signals with a wavelength of 1350nm to 1550nm can avoid harm to human eyes .

In addition, the light emitting module 30 is also provided with a light detector 34 to detect the working state of the light source 31 and the working state of the diffuser 33, so that the working state of the light source 31 and the working state of the diffuser 33 can be detected according to the light detector 34. The state better controls the light source 31. When the diffuser 33 is working normally but the light source 31 is not in a constant power working state, the working current of the light source 31 is increased to ensure that the light emitting module 30 can output a light signal with stable power, which can further improve the acquisition accuracy of depth information. When the diffuser 33 fails to work normally, turning off the light source 31 can reduce the power consumption of the electronic device 1000.

Furthermore, the light emitting module 30 is disposed on the second surface 212 of the cushion block 21, and the light emitting module 30 is electrically connected to the substrate 10 through the conductive member 22, and the cushion block 21 cushions the height of the high light emitting module 30. The height difference between the light emitting module 30 and the light receiving module 40 is reduced, and the light receiving module 40 is prevented from being blocked by the light emitting module 30 to emit light signals, and the light signals emitted by the light emitting module 30 have greater coverage Range, the depth camera 100 can obtain depth information of more objects in the scene, and the obtained depth information is highly complete.

Please refer to FIGS. 4, 8 and 9, in some embodiments, the spacer 21 is further provided with a thermally conductive hole 214, and the thermally conductive hole 214 penetrates the first surface 211 and the second surface 212. The spacer assembly 20 further includes a heat conducting member 23 which is filled in the heat conducting hole 214. The light source 31 is arranged on the heat conducting member 23. The light source 31 generates heat during operation, and if the heat cannot be dissipated in time, it may affect the intensity and frequency of the optical signal emitted by the light source 31 and make the light source 31 unable to maintain a constant power working state. At this time, if the light source 31 is arranged on the heat-conducting member 23, the heat-conducting member 23 can quickly conduct the heat generated by the light source 31 to the substrate 10, and further conduct the heat to the outside through the substrate 10, so that the hardware design can be used The light source 31 is kept in a constant power working state.

Specifically, the heat-conducting member 23 is filled in the heat-conducting hole 214, and the heat-conducting member 23 may be made of a material with better thermal conductivity such as copper and silver. The heat-conducting element 23 is exposed from the first surface 211 and the second surface 212 so that one end of the heat-conducting element 23 is in contact with the light source 31 and the other end is in contact with the substrate 10. The orthographic projection of the light source 31 on the second surface 212 can completely fall onto the heat-conducting member 23, so that the contact area between the light source 31 and the heat-conducting member 23 is larger, and the heat conduction efficiency is improved. In one example, the number of heat conducting holes 214 is multiple, and the plurality of heat conducting holes are arranged at intervals, and the heat conducting member 23 arranged in each heat conducting hole 214 is in contact with the light source 31; in another example, the number of heat conducting holes 214 is Single, the hollow volume of a single heat conduction hole 214 can be set to be larger, for example, greater than the sum of the hollow volumes of the plurality of heat conduction holes 214 when multiple heat conduction holes 214 are opened, so that the single heat conduction hole 214 can be set A larger number of heat-conducting parts 23 improves heat-conducting efficiency.

Further, the heat conducting hole 214 can also be opened in a small top and big bottom shape, that is, the size of the end of the heat conducting hole 214 close to the second surface 212 can be substantially the same as the area of the orthographic projection of the light source 31 on the second surface 212, close to The size of one end of the first surface 211 can be set to be larger than the area of the orthographic projection of the light source 31 on the second surface 212, so as to increase the contact area between the heat conducting member 23 and the substrate 10 and improve the heat conduction efficiency.

Referring to FIG. 4, in some embodiments, when the photodetector 34 is disposed on the second surface 212, the conductive hole 213 can be used for the conductive member 22 to pass through to electrically connect the photodetector 34 and the substrate 10. The photodetector 34 and the conductive member 22 may be electrically connected by wire bonding, or the pins of the photodetector 34 may directly contact the conductive member 22. In addition, the position aligned with the photodetector 34 can also be provided with the above-mentioned thermally conductive hole 214, and the thermally conductive member 23 in the thermally conductive hole 214 can be used to quickly conduct the heat generated by the photodetector 34 to the substrate 10 to Ensure that the light detector 34 is working properly.

In some embodiments, the filter film 37 may not be provided in the light emitting module 30. At this time, the photodetector 37 can be set as an element that can only receive light signals from 1350 nm to 1550 nm. Specifically, the working waveband of the photodetector 34 can be changed by changing the material composition of the photodetector 34, so that the photodetector 34 only works in the waveband of 1350nm-1550nm.

In some embodiments, the light receiving module 40 may not be provided with the filter 44. In this case, the photosensitive element 42 may be a photosensitive element that only receives light signals from 1350 nm to 1550 nm. Specifically, the working wavelength band of the photosensitive element 42 can also be changed by changing the material composition of the photosensitive element 42 so that the photosensitive element 42 only operates in the wavelength band of 1350 nm to 1550 nm.

In some embodiments, the light emitting module 30 and the light receiving module 40 can also be placed on two independent substrates 10 and connected to the main board of the electronic device 1000 through two connectors 60 respectively.

In the description of this specification, reference is made to the terms “certain embodiments”, “one embodiment”, “some embodiments”, “exemplary 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 application. In this specification, the schematic representations of the above-mentioned terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials, or characteristics can be combined in any one or more embodiments or examples in an appropriate manner.

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

Although the embodiments of the present application have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present application. A person of ordinary skill in the art can comment on the foregoing within the scope of the present application. The embodiments undergo changes, modifications, substitutions and modifications, and the scope of this application is defined by the claims and their equivalents.

Claims

A light emitting module, characterized in that the light emitting module includes:

A light source, the light source is used to emit a light signal, and the wavelength of the light signal is 1350nm-1550nm; and

A diffuser, which is used to diffuse the optical signal.
The light emitting module according to claim 1, wherein the light emitting module further comprises a light detector, and the light detector is used to receive the light signal reflected by the diffuser to form a detection electric signal The detected electrical signal is used as a basis for determining whether the light source is in a constant power working state and/or as a basis for determining whether the diffuser is in a normal working state.
The light emitting module according to claim 2, wherein the diffuser includes a light incident surface and a light output surface opposite to each other, the light incident surface is opposite to the light source, and the light output surface is provided with a high The reflective film, the highly reflective film is used to reflect light with a wavelength of 1350 nm to 1550 nm.
The light emitting module according to claim 3, wherein the diffuser comprises a coated area and a non-coated area connected to the coated area, the high reflective film is formed in the coated area, and The non-coated area corresponds to the light signal area emitted by the light source, and the coated area corresponds to the light receiving area of the photodetector.
3. The light emitting module of claim 3, wherein the working wavelength band of the light detector is 1350 nm to 1550 nm.
The light emitting module according to claim 3, wherein a filter film is provided on the photodetector, and the filter film is used to transmit optical signals with a wavelength of 1350 nm to 1550 nm.
A light receiving module, characterized in that the light receiving module includes:

Lens assembly; and

The photosensitive element, the photosensitive element is used to receive only the optical signal passing through the lens assembly and having a wavelength range of 1350 nm to 1550 nm.
7. The light receiving module according to claim 7, wherein the light receiving module further comprises a filter, and the filter is used to transmit only optical signals with a wavelength of 1350 nm to 1550 nm.
The light receiving module according to claim 7, wherein the material of the photosensitive element includes silicon and germanium; or

The material of the photosensitive element includes silicon and indium gallium arsenide.
A depth camera, characterized in that the depth camera comprises:

A light emitting module, the light emitting module includes:

A light source, the light source is used to emit a light signal, and the wavelength of the light signal is 1350nm-1550nm; and

A diffuser, the diffuser used to diffuse the optical signal; and

The light receiving module includes:

Lens assembly; and

The photosensitive element, the photosensitive element is used to receive only the optical signal passing through the lens assembly and having a wavelength range of 1350 nm to 1550 nm.
The depth camera according to claim 10, wherein the light emitting module further comprises a light detector, and the light detector is configured to receive the light signal reflected by the diffuser to form a detection electric signal;

The depth camera further includes a processor, and the processor is configured to:

Determining whether the light source is in a constant power working state and/or determining whether the diffuser is in a normal working state according to the detected electrical signal; and

The light source is controlled according to whether the light source is in a constant power working state and/or whether the diffuser is in a normal working state.
The depth camera according to claim 11, wherein the diffuser comprises a light-incident surface and a light-exit surface opposite to each other, the light-incident surface is opposite to the light source, and a high reflective film is provided on the light-emitting surface The high reflection film is used to reflect light with a wavelength of 1350 nm to 1550 nm.
The depth camera according to claim 12, wherein the diffuser comprises a coated area and a non-coated area connected to the coated area, the high-reflective film is formed in the coated area, and the non-coated area The area corresponds to the light signal area emitted by the light source, and the coating area corresponds to the light receiving area of the photodetector.
The depth camera of claim 12, wherein the working wavelength band of the photodetector is 1350 nm to 1550 nm.
The depth camera of claim 12, wherein a filter film is provided on the photodetector, and the filter film is used to transmit light signals with a wavelength of 1350 nm to 1550 nm.
The depth camera according to claim 10, wherein the light receiving module further comprises a filter, and the filter is used to transmit only light signals with a wavelength of 1350 nm to 1550 nm.
The depth camera of claim 10, wherein the material of the photosensitive element includes silicon and germanium; or

The material of the photosensitive element includes silicon and indium gallium arsenide.
An electronic device, characterized in that, the electronic device includes:

Chassis; and

A depth camera, the depth camera is combined with the housing;

The depth camera includes:

A light emitting module, the light emitting module includes:

A light source, the light source is used to emit a light signal, and the wavelength of the light signal is 1350nm-1550nm; and

A diffuser, the diffuser used to diffuse the optical signal; and

The light receiving module includes:

Lens assembly; and

The photosensitive element, the photosensitive element is used to receive only the optical signal passing through the lens assembly and having a wavelength range of 1350 nm to 1550 nm.
The electronic device according to claim 18, wherein the light emitting module further comprises a light detector, and the light detector is used to receive the light signal reflected by the diffuser to form a detection electric signal;

The depth camera further includes a processor, and the processor is configured to:

Determining whether the light source is in a constant power working state and/or determining whether the diffuser is in a normal working state according to the detected electrical signal; and

The light source is controlled according to whether the light source is in a constant power working state and/or whether the diffuser is in a normal working state.
The electronic device according to claim 19, wherein the diffuser comprises a light-incident surface and a light-exit surface opposite to each other, the light-incident surface is opposite to the light source, and a high reflective film is provided on the light-emitting surface The high reflection film is used to reflect light with a wavelength of 1350 nm to 1550 nm.
The electronic device according to claim 20, wherein the diffuser comprises a coated area and a non-coated area connected to the coated area, the high reflective film is formed in the coated area, and the non-coated area The area corresponds to the light signal area emitted by the light source, and the coating area corresponds to the light receiving area of the photodetector.
The electronic device according to claim 20, wherein the working wavelength band of the photodetector is 1350nm-1550nm.
22. The electronic device according to claim 20, wherein a filter film is provided on the photodetector, and the filter film is used to transmit light signals with a wavelength of 1350 nm to 1550 nm.
18. The electronic device of claim 18, wherein the light receiving module further comprises a filter, and the filter is used to transmit only optical signals with a wavelength of 1350 nm to 1550 nm.
The electronic device according to claim 18, wherein the material of the photosensitive element comprises silicon and germanium; or

The material of the photosensitive element includes silicon and indium gallium arsenide.