Emission module capable of regulating emission energy on the basis of acousto-optic effect, and apparatus and related device

Abstract

Provided in the present application is an emission module based on an acousto-optic effect. The emission module comprises a light source module, at least one acousto-optic deflection module and a control module. The light source module is configured to emit a light beam. The acousto-optic deflection module comprises an acousto-optic interaction medium and an acoustic wave generator, wherein the acoustic wave generator is configured to generate an acoustic wave propagating in a preset direction in the acousto-optic interaction medium. The control module comprises an acousto-optic deflection control unit and an emission energy regulation unit, wherein the acousto-optic deflection control unit is configured to deflect, by means of controlling an acoustic wave frequency applied by the acoustic wave generator, a light beam, which passes through the acousto-optic interaction medium, by a plurality of different preset deflection angles within a preset deflection angle range, such that the light beam serves as a sensing light beam for scanning a detection range, and the emission energy regulation unit is configured to correspondingly regulate the energy of the sensing light beam by means of changing an acoustic wave power applied by the acoustic wave generator. Further provided in the present application are a photoelectric detection apparatus comprising the emission module, and an electronic device.

Description

Transmitting module, device and related equipment for regulating transmitting energy based on acousto-optic effect Technical Field

[0001] The present application relates to the field of photoelectric detection, and in particular to an emission module, device and related equipment for regulating emission energy based on the acousto-optic effect. Background Art

[0002] LiDAR's ranging function is typically based on the Time of Flight (ToF) principle. This involves emitting laser pulses into the measurement scene and measuring the time it takes for the laser pulses to travel back and forth between the LiDAR and the target object to calculate three-dimensional information such as the distance to the target object. Due to its advantages of long sensing range, high accuracy, and low energy consumption, ToF measurement is widely used in consumer electronics, smart driving, AR / VR, and other fields.

[0003] To increase the detection distance and expand the field of view, LiDAR needs to increase the power of the emitted laser pulses. To eliminate interference from ambient light and multiple radars to ensure signal-to-noise ratio and ranging accuracy, LiDAR also needs to increase the number of laser pulses emitted in a single ranging measurement to eliminate noise through statistical methods. However, the high peak power, multiple frequency, and wide pulse width of the laser pulses all mean higher laser radiation energy, which puts a test on the LiDAR's ability to meet human eye safety standards. Summary of the Invention

[0004] In view of this, the present application provides a transmission module, device and related equipment for adjusting transmission energy based on acousto-optic effect, which can improve the problems of the existing technology.

[0005] In a first aspect, the present application provides a transmitting module based on the acousto-optic effect, characterized in that it is configured to transmit a sensing light beam for three-dimensional information detection based on the time-of-flight principle into a detection range, and includes:

[0006] a light source module configured to emit a light beam;

[0007] at least one acousto-optic deflection module, comprising an acousto-optic interaction medium and an acoustic wave generator, wherein the acoustic wave generator is configured to generate an acoustic wave propagating along a preset direction within the acousto-optic interaction medium; and

[0008] The control module includes an acousto-optic deflection control unit and an emission energy adjustment unit. The acousto-optic deflection control unit is configured to control the frequency of the acoustic wave applied by the acoustic wave generator to deflect the light beam passing through the acousto-optic interaction medium to multiple different preset deflection angles within a preset deflection angle range as a sensing light beam for scanning the detection range. The emission energy adjustment unit is configured to adjust the energy of the sensing light beam accordingly by changing the power of the acoustic wave applied by the acoustic wave generator.

[0009] In a second aspect, the present application provides a photoelectric detection device configured to detect the distance of an object within a preset detection range. The photoelectric detection device includes a receiving module, a processing module, and a transmitting module as described above. The receiving module is configured to sense light signals from within the detection range and output corresponding light sensing signals, and the processing module is configured to analyze and process the light sensing signals to obtain three-dimensional information about the object within the detection range.

[0010] In a third aspect, the present application provides an electronic device, comprising an application module and the above-mentioned photoelectric detection device, wherein the application module is configured to implement corresponding functions according to the detection results of the photoelectric detection device.

[0011] Beneficial effects of this application:

[0012] The present application adjusts the emission energy of the sensing light beam by changing the acoustic wave power applied to the acousto-optic deflection module, and can select multiple different acoustic wave power value adjustment intervals for adjustment, which has high flexibility and can also improve the sensitivity of the emission energy adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings.

[0014] FIG1 is a schematic diagram of functional modules of an electronic device provided in one embodiment of the present application;

[0015] FIG2 is a schematic diagram of functional modules of an embodiment of the photoelectric detection device shown in FIG1 ;

[0016] FIG3 is a schematic diagram of a statistical histogram obtained by the processing module in FIG2 ;

[0017] FIG4 is a signal timing diagram of a photoelectric detection device according to an embodiment of the present application when performing detection;

[0018] FIG5 is a schematic diagram of the optical path of an embodiment of the emission module shown in FIG2 ;

[0019] FIG6 is a schematic structural diagram of the acousto-optic deflection module shown in FIG2 ;

[0020] FIG7 is a schematic diagram of the optical path of another embodiment of the emission module in FIG2;

[0021] FIG8 is a schematic diagram of the structure of a photoelectric detection device provided in one embodiment of the present application as an automotive laser radar. DETAILED DESCRIPTION

[0022] 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 represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limitations on the present application. In the description of the present application, it should be understood that the terms "first" and "second" are only used for description and are not to be construed as indicating or implying relative importance or implicitly indicating the number or arrangement order of the indicated technical features. Thus, the technical features defined as "first" and "second" may explicitly or implicitly include one or more of the technical features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integrated connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0024] The disclosure below provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, only the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may reuse reference numbers and / or reference letters in different examples. This repetition is for the purpose of simplifying and clearly stating the present application and does not itself indicate a specific relationship between the various embodiments and / or settings discussed. In addition, the various specific processes and materials provided in the description below are merely examples for implementing the technical solutions of the present application, but those of ordinary skill in the art should appreciate that the technical solutions of the present application may also be implemented by other processes and / or other materials not described below.

[0025] Further, described feature, structure can be combined in one or more embodiments in any suitable manner.In the description below, many specific details are provided so that the embodiments of the present application can be fully understood. However, it will be appreciated by those skilled in the art that even without one or more of the specific details, or by adopting other structures, components etc., the technical scheme of the present application can also be put into practice. In other cases, known structures or operations are not shown or described in detail to avoid blurring the key points of the present application.

[0026] An embodiment of the present application provides a transmitting module based on the acousto-optic effect, characterized in that it is configured to transmit a sensing light beam for performing three-dimensional information detection based on the time-of-flight principle into a detection range, and includes:

[0027] a light source module configured to emit a light beam;

[0028] at least one acousto-optic deflection module, comprising an acousto-optic interaction medium and an acoustic wave generator, wherein the acoustic wave generator is configured to generate an acoustic wave propagating along a preset direction within the acousto-optic interaction medium; and

[0029] The control module includes an acousto-optic deflection control unit and an emission energy adjustment unit. The acousto-optic deflection control unit is configured to control the frequency of the acoustic wave applied by the acoustic wave generator to deflect the light beam passing through the acousto-optic interaction medium to multiple different preset deflection angles within a preset deflection angle range as a sensing light beam for scanning the detection range. The emission energy adjustment unit is configured to adjust the energy of the sensing light beam accordingly by changing the power of the acoustic wave applied by the acoustic wave generator.

[0030] Optionally, in some embodiments, the sensing light beam is first-order diffraction light resulting from diffraction of the light beam through the acousto-optic interaction medium.

[0031] Optionally, in some embodiments, the energy value of the sensing light beam and the corresponding acoustic wave power value have a changing relationship that is a periodic function.

[0032] Optionally, in some embodiments, the emission energy adjustment unit is configured to correspondingly adjust the emission energy of the sensing light beam by simultaneously changing the light emitting power of the light source module.

[0033] Optionally, in some embodiments, two separate acousto-optic deflection modules are included, namely a first acousto-optic deflection module and a second acousto-optic deflection module. The first acousto-optic deflection module is configured to deflect the passing light beam along a first direction to a plurality of different preset deflection angles within a preset deflection angle range, and the second acousto-optic deflection module is configured to deflect the passing light beam along a second direction different from the first direction to a plurality of different preset deflection angles within a preset deflection angle range. The light beam emitted by the light source module is deflected by the first acousto-optic deflection module and the second acousto-optic deflection module respectively to form a sensing light beam that performs a two-dimensional scanning on the detection range. The emission energy adjustment unit adjusts the energy of the sensing light beam by controlling the acoustic wave power applied to at least one of the acousto-optic deflection modules.

[0034] Optionally, in some embodiments, an electro-optical deflection module is further included, wherein the acousto-optic deflection module is configured to deflect the passing light beam along a first direction to a plurality of different preset deflection angles within a preset deflection angle range, and the electro-optical deflection module is configured to deflect the passing light beam along a second direction different from the first direction to a plurality of different preset deflection angles within a preset deflection angle range according to the intensity of the electric field applied thereto. The light beam emitted by the light source module is deflected by the acousto-optic deflection module and the electro-optical deflection module respectively to form a sensing light beam for two-dimensional scanning of the detection range, and the control module adjusts the energy of the sensing light beam by controlling the acoustic wave power applied to the acousto-optic deflection module.

[0035] Optionally, in some embodiments, the light source module further includes a beam reduction optical device, and the beam reduction optical device is configured to reduce the strip-shaped collimated light beam to a preset size before transmitting it to the acousto-optic deflection module.

[0036] Optionally, in some embodiments, the first direction is a horizontal direction, and the second direction is a vertical direction; or, the first direction is a vertical direction, and the second direction is a horizontal direction.

[0037] Embodiments of the present application also provide a photoelectric detection device configured to detect three-dimensional information of an object within a preset detection range, comprising the transmitting module described above, a receiving module, and a processing module. The photoelectric detection device further comprises a receiving module and a processing module. The receiving module is configured to sense light signals from within the detection range and output corresponding light sensing signals, and the processing module is configured to analyze and process the light sensing signals to obtain three-dimensional information of the object within the detection range.

[0038] Optionally, in some embodiments, within the same partition detection period for performing distance detection on a partition along a preset scanning angle within the detection range, the emission energy adjustment unit adjusts the multiple first sensing light beam pulses first emitted within the partition detection period to have a lower first emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules, and then changes the acoustic wave power applied to at least one of the acousto-optic deflection modules based on the analysis of the sensed first sensing light beam pulse echo by the processing module to adjust the emission energy of the multiple second sensing light beam pulses emitted later within the partition detection period.

[0039] Optionally, in some embodiments, if the analysis of the first sensing beam pulse echo shows that there is no object within the preset maximum safety distance, the emission energy adjustment unit adjusts the multiple second sensing beam pulses emitted later within the partition detection period to have a higher second emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules. After emitting the second sensing beam pulse, the processing module obtains the sensing result of the current partition detection period based on the analysis of the second sensing beam pulse echo.

[0040] Optionally, in some embodiments, the second emission energy is equal to or greater than the maximum emission energy required for the maximum distance detection value that the sensing beam pulse must meet along the current scanning angle; or, the second emission energy is less than the maximum emission energy, and the appropriate emission energy is determined based on the object distance information obtained by analyzing the echo of the first sensing beam pulse.

[0041] Optionally, in some embodiments, if the analysis of the first sensing beam pulse echo shows that there is an object within a preset maximum safety distance, the transmitting module stops emitting the sensing beam pulse, and the processing module directly outputs the analysis result of the first sensing beam pulse echo as the sensing result of the current partition detection period.

[0042] Optionally, in some embodiments, if the analysis of the first sensing beam pulse echo shows that there is an object within a preset maximum safety distance, the emission energy adjustment unit can maintain the acoustic wave power applied to the acousto-optic deflection module so that the multiple second sensing beam pulses emitted later within the partition detection period still have a lower first emission energy. After emitting the second sensing beam pulse, the processing module obtains the sensing result of the current partition detection period based on the analysis of the first sensing beam pulse echo and the second sensing beam pulse echo.

[0043] Optionally, in some embodiments, if the analysis of the first sensing beam pulse echo shows that there is an object within a preset maximum safety distance, the emission energy adjustment unit adjusts the multiple second sensing beam pulses emitted later within the same partition detection period to have a third emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules. The third emission energy is positively correlated with the object distance obtained by the processing module through the analysis of the first sensing beam pulse echo, and does not exceed the relevant safety standards that should be met at the object distance.

[0044] Optionally, in some embodiments, the emission energy adjustment unit is configured to emit a plurality of second sensing beam pulses with a second emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules if the moving speed of the photoelectric detection device exceeds a preset speed threshold. The second emission energy is equal to or greater than the maximum emission energy required for the maximum distance detection value that the sensing beam pulse must meet along the current scanning angle.

[0045] An embodiment of the present application also provides an electronic device, which includes the photoelectric detection device. The electronic device realizes the corresponding function based on the three-dimensional information obtained by the photoelectric detection device. The electronic device is, for example, a mobile phone, a car, a robot, an access control / monitoring system, a smart door lock, an unmanned vehicle, a drone, etc. The three-dimensional information is, for example, proximity information, depth information, distance information, coordinate information, etc. of an object within the detection range. Among them, the three-dimensional information can be used, for example, in 3D modeling, identity recognition, automatic driving, machine vision, monitoring, drone control, augmented reality (AR) / virtual reality (VR), simultaneous localization and mapping (SLAM), object proximity judgment and other fields, and this application does not limit this.

[0046] The photoelectric detection device, for example, can be a laser radar (LiDAR), which can be used to obtain three-dimensional information about objects within its detection range. Such LiDARs are used, for example, in intelligent vehicles, intelligent aircraft, 3D printing, VR, AR, service robots, and other fields. Taking intelligent vehicles as an example, a LiDAR is installed in an intelligent vehicle. The LiDAR scans the surrounding environment by rapidly and repeatedly emitting laser beams to obtain point cloud data reflecting the shape, position, and movement of one or more objects in the surrounding environment. Specifically, the LiDAR emits a laser beam into the surrounding environment and receives echo beams reflected by various objects in the surrounding environment. By calculating the time delay between the emission time of the laser beam and the return time of the echo beam (i.e., the time of flight), the distance / depth information of each object is determined. The LiDAR can also determine angular information describing the orientation of the laser beam's detection range. By combining the distance / depth information of each object with the angular information of the laser beam, a three-dimensional map of each object in the scanned surrounding environment is generated. This three-dimensional map can be used to guide the intelligent driving of the unmanned vehicle.

[0047] Hereinafter, embodiments in which the photoelectric detection device is applied to electronic equipment will be described in detail with reference to the accompanying drawings.

[0048] Figure 1 is a schematic diagram of the functional modules of a photoelectric detection device provided in an embodiment of the present application, as applied to an electronic device. Figure 2 is a schematic diagram of the functional modules of a photoelectric detection device provided in an embodiment of the present application.

[0049] 1 and 2 , the electronic device 1 includes a photoelectric detection device 10. The photoelectric detection device 10 can detect an object 2 within a detection range to obtain three-dimensional information about the object 2. The detection range can be defined as the three-dimensional spatial range within which the photoelectric detection device 10 can effectively detect three-dimensional information, and can also be referred to as the field of view angle or field of view range of the photoelectric detection device 10. The three-dimensional information can include, for example, but is not limited to, one or more of proximity information of the object 2, depth information on the surface of the object 2, distance information to the object 2, and spatial coordinate information of the object 2.

[0050] The electronic device 1 may include an application module 20, which is configured to perform preset operations or implement corresponding functions based on the detection results of the photoelectric detection device 10. For example, but not limited to: determining whether an object 2 is within a preset detection range in front of the electronic device 1 based on the proximity information of the object 2; or controlling the movement of the electronic device 1 to avoid obstacles based on the distance information of the object 2; or implementing 3D modeling, identity recognition, machine vision, etc. based on the depth information of the surface of the object 2. In other words, the application module 20 may include a combination of the hardware required to perform the above operations and implement the above functions, and the software required to control and coordinate the operation of the hardware.

[0051] The electronic device 1 may further include a storage medium 30, which can support the storage needs of the electronic device 1 and / or the photoelectric detection device 10 during operation. As shown in FIG1 , in some embodiments, the storage medium 30 can be disposed within the electronic device 1. As shown in FIG2 , in some embodiments, the storage medium 30 can also be disposed within the photoelectric detection device 10.

[0052] The electronic device 1 may further include a processor 40 to support data processing requirements during operation of the electronic device 1 and / or the photoelectric detection device 10. As shown in FIG1 , in some embodiments, the processor 40 may be disposed within the electronic device 1. As shown in FIG2 , in some embodiments, the processor 40 may also be disposed within the photoelectric detection device 10.

[0053] Optionally, in some embodiments, the photoelectric detection device 10 may be, for example, a dToF measurement device that performs three-dimensional information sensing based on the direct time of flight (dToF) principle. The dToF measurement device may emit a sensing light beam within a detection range and receive a sensing light beam reflected back from an object 2 within the detection range. The time difference between the emission and reception moments of the reflected sensing light beam is referred to as the flight time t of the sensing light beam. The three-dimensional information of the object 2 may be obtained by calculating half the distance traveled by the sensing light beam within the flight time t. Where c is the speed of light.

[0054] In some other embodiments, the photoelectric detection device 10 may also be an indirect time of flight (iToF) measurement device that performs three-dimensional information sensing based on the iToF measurement principle. The iToF measurement device obtains three-dimensional information of the object 2 by comparing the phase difference between the sensing light beam when it is emitted and when it is reflected and received.

[0055] In the following embodiments of the present application, the photoelectric detection device 10 is mainly described as a dToF measurement device as an example.

[0056] In some embodiments, as shown in FIG2 , the photoelectric detection device 10 includes a transmitting module 12, a receiving module 14, and a processing module 15. The transmitting module 12 is configured to transmit a sensing light beam into a detection range to detect three-dimensional information of an object 2 within the detection range. Part of the sensing light beam will be reflected by the object 2 and returned. The reflected sensing light beam echo carries the three-dimensional information of the object 2, and part of the sensing light beam echo can be sensed by the receiving module 14 to obtain the three-dimensional information of the object 2. The receiving module 14 is configured to sense light signals from the detection range and output corresponding light sensing signals. The three-dimensional information detection of the object 2 within the detection range is achieved by analyzing the light sensing signals. It is understood that the light signals sensed by the receiving module 14 can be photons, for example, including photons of the sensing light beam echo reflected by the object 2 within the detection range and photons of ambient light within the detection range. The processing module 15 is configured to analyze and process the light sensing signal to obtain the moment when the sensing beam echo is sensed by the receiving module 14, and obtain the three-dimensional information of the object 2 based on the time difference between the emission moment of the sensing beam and the moment when it is reflected back and sensed.

[0057] The processing module 15 may be provided on the photoelectric detection device 10 . It should be understood that, in some other embodiments, all or part of the functional units of the processing module 15 may also be provided on the electronic device 1 .

[0058] In some embodiments, the sensing beam can be, for example, a plurality of laser pulses emitted in sequence. The emission module 12 is configured to emit the laser pulses as a sensing beam according to a preset time sequence. Specifically, the emission module 12 emits sensing beam pulses to partitions in different directions within the detection range in a time-sharing manner according to a preset scanning method for distance detection, and emits a plurality of sensing beam pulses for each partition according to a corresponding preset time sequence. After completing the emission of a plurality of sensing beam pulses for one of the partitions, the distance information of the partition can be obtained. This process can be regarded as a partition detection period, and after scanning a plurality of partitions one by one, it is regarded as completing a frame detection of the entire detection range, and the distance information of all partitions in the entire detection range can be obtained, which can be used to construct a point cloud of a frame of the entire detection range. That is, a frame detection of the detection range includes a plurality of partition detection periods corresponding to the partition scanning.

[0059] Optionally, the sensing light beam is, for example, visible light, infrared light or near-infrared light, with a wavelength range of, for example, 390 nanometers (nm)-780nm, 700nm-1400nm, 800nm-1000nm, 900nm-1600nm, etc.

[0060] Please refer to Figures 2, 3 and 4. Figure 3 is a schematic diagram of the statistical histogram obtained by the processing module 15 in Figure 2. In some embodiments, the processing module 15 may include a timing unit 152, a statistics unit 154, a flight time acquisition unit 156 and a three-dimensional information acquisition unit 158.

[0061] The timing unit 152 is configured to determine the reception time of the light signal sensed by the receiving module 14. During the detection process, the photoelectric detection device 10 emits multiple sensing beams through the transmitting module 12. The timing unit 152 starts timing each time the transmitting module 12 emits a sensing beam to record the reception time of the light signal sensed by the receiving module 14 between two adjacent sensing beam emissions. During this period, the receiving module 14 outputs a corresponding light sensing signal for each light signal received. The timing unit 152 records the reception time of the sensed light signal based on the light sensing signal output by the receiving module 14 and counts the time in a time bin corresponding to the reception time to form a corresponding light signal count. The time bin is the minimum time unit Δt in which the timing unit 152 records the moment when the light sensing signal is generated. It can reflect the accuracy of the time recording of the light signal reception time by the timing unit 152. The finer the time bin, the higher the accuracy of the time recording. In some embodiments, the timing unit 152 can implement the timing function, for example, through a time-to-digital converter (TDC) 1522. The TDC 1522 can be connected to the corresponding photosensitive pixel 142 on the receiving module 14 and configured to record the reception time of the sensed light signal based on the light sensing signal generated by the corresponding photosensitive pixel 142. For example, the TDC 1522 is synchronously triggered to start timing each time a sensing light beam is emitted, and subsequently stops timing in response to the light sensing signal generated by the corresponding photosensitive pixel 142, and the time period is used as the reception time of the corresponding light signal that triggered the light sensing signal.

[0062] In some embodiments, the timing unit 152 may include a counting memory 1524, which has a counting storage space allocated according to the time bins. Each time the TDC 1522 records the reception time of an optical signal, it accumulates one in the counting storage space of the corresponding time bin, that is, the optical signal count in the corresponding time bin increases by one. The optical signal count value of each time bin corresponds to the number of optical signals received at the moments represented by the time bin in the multiple emission periods of the sensing light beam.

[0063] The statistical unit 154 is configured to perform statistics on the accumulated optical signal counts in each time bin to obtain a statistical histogram that can reflect the time distribution of the number of optical signals sensed by the receiving module 14 during multiple sensing light beam emissions. As shown in FIG3 , the abscissa of the statistical histogram represents the timestamp of each corresponding time bin, and the ordinate of the statistical histogram represents the accumulated optical signal count values ​​in each corresponding time bin. In some embodiments, the statistical unit 154 may include a histogram circuit 1544 (see FIG2 ), which is configured to perform statistics on the optical signal counts in each time bin to generate a statistical histogram. It should be understood that the statistical unit 154 performs statistical analysis on the corresponding accumulated optical signal counts during multiple sensing light beam emissions within a partition detection period. In order to make the counts have mathematical statistical significance, the number of sensing light beam emissions within a partition detection period can be as many as hundreds, thousands, tens of thousands, hundreds of thousands, or even millions of times.

[0064] During the sensing process, a large number of ambient light photons are also sensed by the receiving module 14, generating corresponding optical signal counts. The probability of these ambient light photons being sensed and remaining counted in each time bin tends to be similar, forming a noise background within the detection range. In scenes with strong ambient light, the average level of the noise background is relatively high, while in scenes with weak ambient light, the average level of the noise background is relatively low. Furthermore, the optical signal counts generated by the sensing beam echo reflected from object 2 are superimposed on the noise background, causing the optical signal counts in the time bin corresponding to the moment the sensing beam echo is sensed to be significantly higher than the optical signal counts in other time bins, thereby forming a prominent signal peak. It is understood that the height of the signal peak count value is affected by factors such as the optical power of the sensing beam, the reflectivity of the object 2, and the detection range of the photoelectric detection device 10. The width of the signal peak is affected by factors such as the pulse width of the emitted sensing beam, the photoelectric conversion elements of the receiving module 14, and the timing jitter of the TDC 1522. Thus, the time-of-flight acquisition unit 156 can obtain the time-of-flight of the relevant sensing light beam reflected by the object 2 based on the time difference between the timestamp t1 of the time bin corresponding to the peak value of the signal peak and the emission time t0 of the relevant sensing light beam that generated the signal peak. The three-dimensional information acquisition unit 158 ​​can be configured to obtain three-dimensional information between the object 2 that reflected the sensing light beam and the photoelectric detection device 10 based on the flight time of the sensing light beam determined by the statistical histogram, for example, the distance between the object 2 within the detection range and the photoelectric detection device 10.

[0065] It should be understood that the transmitting module 12 and the receiving module 14 are arranged side by side, with the light-emitting surface of the transmitting module 12 and the light-entering surface of the receiving module 14 both facing the same side of the photoelectric detection device 10. The distance between the transmitting module 12 and the receiving module 14 can range from 2 millimeters (mm) to 20 mm, for example. Since the transmitting module 12 and the receiving module 14 are relatively close to each other, the transmission path of the sensing light beam from the transmitting module 12 to the object 2 and the return path from the object 2 to the receiving module 14 after reflection are not completely equal, but both are much larger than the distance between the transmitting module 12 and the receiving module 14 and can be considered to be approximately equal. Therefore, the distance between the object 2 and the photoelectric detection device 10 can be calculated based on the product of half the flight time t of the sensing light beam reflected back by the object 2 and the speed of light c.

[0066] In some embodiments, as shown in FIG2 , the receiving module 14 may include a photoelectric sensor 140 and a receiving optical device 144. The receiving optical device 144 is disposed on the light incident side of the photoelectric sensor 140 and is configured to transmit the optical signal from the detection range to the photoelectric sensor 140 for sensing. For example, the receiving optical device 144 may include a receiving lens (not shown). Optionally, the receiving lens may include a single lens or multiple lenses. The photoelectric sensor 140 is configured to sense the optical signal transmitted from the detection range via the receiving optical device 144 and output a corresponding light sensing signal.

[0067] In some embodiments, the receiving module 14 may also include a peripheral circuit (not shown) composed of one or more devices such as a signal amplifier and an analog-to-digital converter (ADC), and the peripheral circuit may be partially or fully integrated into the photoelectric sensor 140.

[0068] Optionally, the photosensor 140 may include a single photosensitive pixel 142 or a plurality of photosensitive pixels 142 forming a photosensitive pixel array. The detection range of the photoelectric detection device 10 may include multiple sub-regions located at different locations. The photosensitive pixels 142 of the photosensor 140 each have a corresponding sub-region within the detection range. The light signal returned from each sub-region is propagated through the receiving optical device 144 to the corresponding photosensitive pixel 142 for sensing. That is, the sub-region corresponding to each photosensitive pixel 142 can be considered as the spatial range encompassed by the field of view formed by the receiving optical device 144 for that photosensitive pixel 142. Thus, when the sensing beam emitted by the transmitting module 12 scans across the sub-region and an object 2 is present on the sub-region, the sensing beam echo reflected from the object 2 is propagated through the receiving optical device 144 to the corresponding photosensitive pixel 142 for sensing. That is, the light signal returned from the sub-region includes photons from the ambient light in the sub-region and, when an object 2 is present in the sub-region, also includes the sensing beam echo projected onto the sub-region and reflected by the object 2.

[0069] One of the photosensitive pixels 142 may include a single photoelectric conversion device or a plurality of photoelectric conversion devices. The photoelectric conversion device is configured to sense the received light signal and convert it into a corresponding electrical signal as the light sensing signal output. Optionally, the photoelectric conversion device is, for example, a single photon avalanche diode (SPAD), an avalanche photon diode (APD), a silicon photomultiplier (SiPM) formed by connecting multiple SPADs in parallel, and / or other suitable photoelectric conversion elements.

[0070] As shown in FIG2 , the transmitting module 12 includes a light source module 122 and at least one acousto-optic deflection module 124. The light source module 122 is configured to emit a light beam, and the acousto-optic deflection module 124 is configured to deflect the light beam emitted by the light source module 122 to a plurality of different preset deflection angles within a preset deflection angle range according to the frequency of the applied sound wave. Thus, the deflection angle of the light beam by the acousto-optic deflection module 124 can be controlled by adjusting the frequency of the applied sound wave.

[0071] In some embodiments, the transmitting module 12 may further include at least one secondary deflection module 126. The secondary deflection module 126 is configured to further deflect the light beam deflected by the acousto-optic deflection module 124 by a preset angle within a preset deflection angle range.

[0072] It should be understood that, in some embodiments, the secondary deflection module 126 can use the acousto-optic effect to deflect the light beam, just like the acousto-optic deflection module 126; in some other embodiments, the secondary deflection module 126 can also use other methods to achieve the deflection of the light beam, for example: the secondary deflection module 126 can be an electro-optic deflector, a liquid crystal polarization grating, a lens or a lens group, a super lens, etc.

[0073] It should be understood that, in some embodiments, the number of the secondary deflection modules 126 may be two or more, so as to expand the deflection angle range of the sensing light beam emitted by the entire transmitting module 12 through multiple deflections.

[0074] It should be understood that in some embodiments, the direction in which the secondary deflection module 126 deflects the light beam can differ from the direction in which the acousto-optic deflection module 124 deflects the light beam, thereby achieving two-dimensional deflection of the sensing light beam. For example, the acousto-optic deflection module 124 deflects the light beam in the horizontal direction, while the secondary deflection module 126 deflects the light beam in the vertical direction. The direction of the deflected light beam here is different from the emission direction of the light beam. The beam deflection direction can be understood as the direction in which the emission direction of the light beam tends to change when the emission direction of the light beam is changed.

[0075] The acousto-optic deflection module 124 is capable of deflecting the passing light beam with high precision, but the angular range of the deflected light beam is too small. Therefore, one or more secondary deflection modules 126 are set on the light-emitting side of the acousto-optic deflection module 124 to further deflect the light beam deflected by the acousto-optic deflection module 124. This can meet the requirements of large-angle high-precision scanning and can also realize two-dimensional deflection of the sensing light beam.

[0076] Referring to FIG4 , the light source module 122 includes one or more light-emitting units 1220, each configured to emit a light beam. The light-emitting unit 1220 may be a light-emitting structure in the form of a vertical cavity surface emitting laser (VCSEL), an edge emitting laser (EEL), a light emitting diode (LED), a laser diode (LD), a fiber laser, or the like. The edge emitting laser may be a Fabry Perot (FP) laser, a distributed feedback (DFB) laser, an electro-absorption modulated laser (EML), or the like, and the present embodiment is not limited thereto. In some embodiments, the light source module 122 may use a collimating optical device 1222 such as a super lens or a cylindrical lens to collimate the light beam emitted by the light emitting unit 1220 to improve the collimation of the light beam emitted by the light source module 122 .

[0077] In some embodiments, the light source module 122 may further include a beam reduction optical device 1223, which can be used to narrow the cross-sectional size of the light beam, that is, the size of the light beam in a cross section perpendicular to the propagation direction of the light beam. The beam reduction optical device 1223 can be arranged in the optical path before the light beam enters the acousto-optic deflection module 124, and is configured to reduce the light beam emitted by the light source module 122 to a preset size before transmitting it to the acousto-optic deflection module 124. Since the incident area of ​​the acousto-optic deflection module 124 for receiving the light beam has a certain size, in order to ensure that all light beams incident on the acousto-optic deflection module 124 enter from the incident area, it is necessary to modulate the light beam to a size that matches the incident area before transmitting it to the acousto-optic deflection module 124. It should be understood that in other embodiments, if the size of the light beam emitted by the light source module 122 after collimation already meets the requirements of the incident acousto-optic deflection module 124, the beam reduction optical device 1223 can also be omitted.

[0078] In some embodiments, the light source module 122 may further include a linear polarizer 1221. The linear polarizer 1221 is disposed on the optical path of the light beam before it enters the acousto-optic deflection module 124 and is configured to convert the light beam into linearly polarized light with a predetermined polarization state before entering the acousto-optic deflection module 124. It should be understood that in other embodiments, the linear polarizer 1221 may be omitted if other optical elements can convert the light beam into linearly polarized light with a predetermined deflection state before the light beam is transmitted to the acousto-optic deflection module 124.

[0079] In the embodiment of FIG4 , the beam reduction optical device 1223 is disposed between the light emitting unit 1220 and the linear polarizer 1221. It should be understood that in other embodiments, the arrangement order of the beam reduction optical device 1223 and the linear polarizer on the optical path can be interchanged, as long as both are disposed in the optical path before the light beam enters the acousto-optic deflection module 124. This application does not impose any specific limitation on this.

[0080] As shown in FIG5 , in some embodiments, the acousto-optic deflection module 124 includes an acousto-optic interaction medium 1241 and an acoustic wave generator 1242. The acousto-optic interaction medium 1241 has a preset light incident surface 1244, a light exit surface 1246, and an acoustic wave incident surface 1248. The acoustic wave generator 1242 is disposed on the acoustic wave incident surface 1248 and is configured to generate acoustic waves propagating along a preset direction within the acousto-optic interaction medium 1241. The light beam emitted by the light source module 122 enters the acousto-optic interaction medium 1241 from the light incident surface 1244 along a preset incident angle. Under the action of the acoustic wave, the acousto-optic interaction medium 1241 deflects the light beam in the propagation direction, and the deflected light beam is emitted from the light exit surface 1246.

[0081] The incident angle can be defined as the angle between the incident direction of the light beam and the normal direction of the light incident surface 1244. In some embodiments, the material of the acousto-optic interaction medium 1241 is tellurium dioxide (TeO2), the incident angle ranges from 2 to 10 degrees, and there is a preset off-axis angle θ between the propagation direction of the sound wave in the tellurium dioxide crystal and the lattice direction [1, 1, 0] of the tellurium dioxide crystal. α (Not shown in the picture).

[0082] In some embodiments, the sound wave generator 1242 may be a piezoelectric transducer, which generates ultrasonic waves that propagate into the acousto-optic interaction medium 1241 to deflect the propagation direction of a light beam passing through the acousto-optic interaction medium 1241 along a preset incident angle.

[0083] It should be understood that the propagation of sound waves in the acousto-optic interaction medium 1241 will cause the refractive index inside the acousto-optic interaction medium 1241 to change. By properly configuring the parameters, the incident light beam can undergo anomalous Bragg diffraction in the acousto-optic interaction medium 1241 under the action of the sound wave. The propagation direction of the resulting diffracted light beam is deflected compared to the propagation direction of the incident light beam. The deflection angle α is related to the frequency f of the sound wave by formula (1):

[0084] Among them, θ d is the exit angle of the diffracted beam, representing the propagation direction of the diffracted beam, θ iis the incident angle of the incident light beam, representing the propagation direction of the incident light beam, λ is the wavelength of the incident light beam and the diffracted light beam, n represents the refractive index of the acousto-optic interaction medium 1241, and V is the off-axis angle θ with the α The relevant function value is recorded as V = V(θ a ), the above-mentioned parameters of reasonable configuration include the wavelength, polarization state, incident angle, propagation direction of the incident light beam, the frequency and propagation direction of the acoustic wave, etc. Therefore, by changing the frequency of the acoustic wave applied to the acousto-optic interaction medium 1241, the deflection angle of the light beam passing through the acousto-optic interaction medium 1241 can be controlled. When the frequency of the acoustic wave changes by Δf, the deflection angle of the light beam changes accordingly, that is, the scanning angle is

[0085] It should be noted that the above-mentioned deflection angle α and scanning angle Δα both refer to the angle inside the acousto-optic interaction medium 1241. In actual application, the angle outside the acousto-optic interaction medium 1241 is used. According to the law of refraction, the angle outside the acousto-optic interaction medium 1241 needs to be multiplied by the corresponding refractive index factor. In addition, since the propagation of sound waves takes time, when the frequency of the sound wave just starts to change from f1 to f2, the sound wave frequency in the part of the acousto-optic interaction medium 1241 that is adjacent to the sound wave generator 1242 switches from f1 to f2, and the deflection angle of the light beam changes from α1 to α2. The sound wave frequency and the deflection angle of the light beam in the rest of the acousto-optic interaction medium 1241 have not had time to change. If the sound wave propagates through the entire area through which the light beam passes in the acousto-optic interaction medium 1241, that is, the width of the acousto-optic interaction medium 1241, the time required is called the sound wave transit time. After the transit time, the sound wave frequency in the entire acousto-optic interaction medium 1241 changes from f1 to f2, and the deflection angle of the light beam completely changes to α2. Therefore, when adjusting the sound wave frequency to change the light beam deflection angle, the deflection time τ required for the light beam to complete one deflection can be considered to be equal to the sound wave transit time. The calculation of the deflection time τ satisfies the following relationship (2):

[0086] Wherein, W is the incident aperture of the light beam on the acousto-optic interaction medium 1241, that is, the width of the light beam incident on the acousto-optic interaction medium 1241, which is usually equal to the width of the acousto-optic interaction medium 1241, and V is the off-axis angle θ α The relevant function value is recorded as V = V(θ a ).

[0087] The wave vectors between the diffracted light beam, the incident light beam and the acoustic wave in the acousto-optic interaction medium 1241 need to satisfy the momentum matching condition in order to form a stable and coherent diffracted light beam in the acousto-optic interaction medium 1241. The incident angle of the light beam that produces anomalous Bragg diffraction will change with the change of the acoustic wave frequency. However, in actual applications, the incident angle of the light beam in the acousto-optic interaction medium 1241 remains unchanged. As the acoustic wave frequency changes, the momentum matching condition no longer holds. The further away from the momentum matching condition, the more the diffraction efficiency decreases. The acoustic wave frequency range that can effectively complete anomalous Bragg diffraction is called the Bragg bandwidth. In some embodiments, the wavelength of the sensing beam is 905 nm, and the material of the acousto-optic interaction medium 1241 is tellurium dioxide crystal. The resulting Bragg bandwidth of the acousto-optic deflection module 124 is approximately 30 megahertz (MHz), the scanning angle is approximately 40 milliradians (mrad), or approximately 2.3 degrees, the deflection time τ required to complete a beam deflection is approximately 10 microseconds (μs), the acoustic wave frequency variation accuracy is approximately 30 kilohertz (kHz), and the corresponding scanning angle variation accuracy is approximately 0.04 mrad. Acousto-optic deflection in a tellurium dioxide crystal using anomalous Bragg diffraction requires that the incident beam have a right-handed e-light component. Optionally, if the incident beam is linearly polarized e-light, the diffracted beam emitted after acousto-optic deflection is linearly polarized o-light; if the incident beam is right-handed circularly polarized light, the diffracted beam emitted after acousto-optic deflection is left-handed circularly polarized light. The utilization rate of the outgoing diffracted light beam is determined by the ellipticity of the eigenmode right-handed e-light of the incident light beam, and the ellipticity of the eigenmode right-handed e-light is determined by the wavelength and incident angle of the incident light and the material properties of the acousto-optic interaction medium 1241.

[0088] As shown in FIG2 , the photoelectric detection device 10 further includes a control module 18 , which is configured to control the transmitting module 12 to emit a sensing beam to scan the detection range, and to control the receiving module 14 to sense the beam returned from the detection range in coordination with the scanning of the sensing beam.

[0089] In some embodiments, the control module 18 may include a light source control unit 182 , an acoustic-optical deflection control unit 184 , and a sensing control unit 186 .

[0090] The light source control unit 182 is configured to control the light source module 122 to emit sensing beam pulses according to a preset time sequence. As previously mentioned, to ensure that the time-correlated single photon counting method used in dToF measurement has mathematical statistical significance, the light source control unit 182 controls the corresponding light source module 122 to emit multiple sensing beam pulses according to a preset time sequence within a partitioned detection period, such as dozens, hundreds, thousands, tens of thousands, or even millions of sensing beam pulses. The emission of one sensing beam pulse corresponds to one sensing period, meaning that one partitioned detection period includes multiple sensing periods.

[0091] It should be understood that the duration of the sensing period can be set based on the maximum distance detection value that the detected partition must meet, and should be at least greater than the photon flight time corresponding to the maximum distance detection value. Multiple different sensing periods belonging to the same partition detection period can be set to have the same duration.

[0092] It should be understood that in some embodiments, for multiple different sensing time periods, the corresponding sensing beam pulses can be emitted at the same time of the sensing time period, for example: all are emitted at the starting time of the sensing time period; and in some other embodiments, for multiple different sensing time periods, the corresponding sensing beam pulses can also be emitted at different times within the sensing time period to prevent interference between different photoelectric detection devices 10 or reduce crosstalk caused between adjacent photosensitive pixels on the receiving module. The above-mentioned multiple different sensing time periods can belong to the same partition detection time period or belong to different partition detection time periods.

[0093] It should be understood that in some embodiments, the length of the sensing period when scanning and sensing partitions located at different angular orientations within the detection range may be different. For example, the length of the sensing period in the partition detection period is positively correlated with the maximum distance detection value that the corresponding detection area must meet. For a detection area with a larger maximum distance detection value, the sensing period for implementing the corresponding sensing is longer; for a detection area with a smaller maximum distance detection value, the sensing period for implementing the corresponding sensing is shorter.

[0094] The sensing control unit 186 is configured to control the relevant photosensitive pixels 142 to perform sensing during corresponding sensing periods, thereby counting light signals returned from the detection range. It should be understood that in some embodiments, the sensing control unit 142 controls a portion of the photosensitive pixels 142 to operate in conjunction with the receiving optical device 144 to sense light signals returned from a predetermined position, with the corresponding photosensitive pixels 142 operating in accordance with the scanning direction of the current sensing beam pulse. Thus, when the sensing beam pulses scan different directions of the detection range during different segmented detection periods, the sensing control unit 142 controls the corresponding photosensitive pixels 142 to perform sensing.

[0095] It should be understood that in some embodiments, the light source control module 182 controls the light source module 122 to periodically emit sensing beam pulses at a preset frequency, and the sensing control unit 142 can control the relevant photosensitive pixels 142 to periodically perform sensing at the same preset frequency as the sensing period. Optionally, within the same sensing period in which emission and sensing correspond to each other, the time when the relevant photosensitive pixels 142 begin sensing can be synchronized or asynchronous with the time when the corresponding sensing beam pulses are emitted.

[0096] The acousto-optic deflection control unit 184 is configured to control the acousto-optic deflection module 124 to deflect the passing light beam by a preset deflection angle within a corresponding deflection angle range. As previously described, the acousto-optic deflection control unit 184 can control the deflection angle of the passing light beam by the acousto-optic deflection module 124 by adjusting the frequency of the acoustic wave applied to the acousto-optic interaction medium 1241. The deflection time τ required for the acousto-optic deflection module 124 to change the beam deflection angle once is approximately 10 microseconds. It should be understood that for each beam deflection angle, the transmitting module 12 needs to emit multiple sensing beam pulses to detect distance information in the direction illuminated by the beam deflection angle. The number of sensing beam pulses emitted by the transmitting module 12 along different beam deflection angles can be different. For example, the number of sensing beam pulses emitted along the direction illuminated by each beam deflection angle can be set based on the maximum distance detection value that the photoelectric detection device 10 must meet in the direction illuminated by each beam deflection angle. A sensing time period corresponding to the number of sensing beam pulses is set within the partitioned detection period associated with the beam deflection angle.

[0097] During use, the acousto-optic deflection control unit 184 controls the acousto-optic deflection module 124 to deflect the light beam within a corresponding deflection angle range with a preset acousto-optic deflection accuracy. For each preset deflection angle of the light beam, the light source control unit 182 controls the light source module 122 to emit sensing beam pulses according to a preset time sequence. The sensing control unit 186 controls the associated photosensitive pixels 142 to sense the light signal returning from the direction corresponding to the beam deflection angle, thereby performing three-dimensional detection in the direction corresponding to the beam deflection angle.

[0098] It should be understood that the acousto-optic deflection control unit 184 may include at least a driving circuit of the sound wave generator 1242 to control the frequency of the sound waves applied to the acousto-optic deflection module 124 .

[0099] In some embodiments, corresponding to the secondary deflection module 126 in the transmitting module 12, the control module 18 may further include one or more secondary deflection control units 188 configured to control the corresponding secondary deflection module 126 to deflect the passing light beam by a predetermined deflection angle within a corresponding deflection angle range. It should be understood that the specific control method of the secondary deflection control unit 188 is related to the type of secondary deflection module 126 being controlled. For example, if the secondary deflection module 126 is also an acousto-optic deflection module, the corresponding secondary deflection control unit 188, similar to the acousto-optic deflection control unit 184, controls the deflection angle of the passing light beam by the secondary deflection module 126 by adjusting the frequency of the acoustic wave applied to the acousto-optic interaction medium 1241. If the secondary deflection module 126 is a liquid crystal polarization grating, the corresponding secondary deflection control unit 188 controls the deflection angle of the passing light beam by controlling the voltage applied to the liquid crystal polarization grating and / or half-wave plate.

[0100] If the secondary deflection module 126 is an electro-optical deflection module, the corresponding secondary deflection control unit 188 controls the deflection angle of the passing light beam by adjusting the electric field strength applied to the electro-optical deflection module 126. In some embodiments, the acousto-optic deflection module 124 is configured to deflect the passing light beam along a first direction by a plurality of different preset deflection angles within a preset deflection angle range, and the electro-optical deflection module 126 is configured to deflect the passing light beam along a second direction different from the first direction by a plurality of different preset deflection angles within a preset deflection angle range based on the applied electric field strength. The light beam emitted by the light source module 122, after being deflected by the acousto-optical deflection module 124 and the electro-optical deflection module 126, forms a sensing light beam that performs a two-dimensional scan of the detection range. Optionally, the first direction may be horizontal, and the second direction may be vertical; alternatively, the first direction may be vertical, and the second direction may be horizontal.

[0101] In some embodiments, the control module 18 may further include an emission energy adjustment unit 189 configured to adjust the energy of the light beam emitted after being deflected by at least one of the acousto-optic deflection modules 124, thereby adjusting the energy of the sensing light beam emitted by the entire emission module 12.

[0102] As mentioned above, the acousto-optic deflection module 124 deflects the passing light beam by utilizing the anomalous Bragg diffraction of the light beam in the acousto-optic interaction medium 1241. The anomalous Bragg diffraction of the light beam in the acousto-optic interaction medium 1241 only considers the zero-order light and the first-order diffraction light that are not deflected, wherein the deflection angle of the first-order diffraction light relative to the incident light beam is proportional to the frequency of the sound wave, and the zero-order light does not participate in the scanning, that is, the sensing light beam in the subsequent optical path is the first-order diffraction light of the light beam diffracted by the acousto-optic interaction medium 1241.

[0103] If the diffraction efficiency η is defined as the ratio of the optical power of the first-order diffracted light to the total optical power, the diffraction efficiency is highest when the wave vectors between the incident light beam, the outgoing first-order diffracted light beam, and the acoustic wave meet the momentum matching condition. In practical applications, the acousto-optic deflection module 124 is usually designed to meet the momentum matching condition at the center frequency of the Bragg bandwidth, while the acousto-optic momentum matching condition is approximately met at other acoustic wave frequencies within the Bragg bandwidth. When the momentum matching condition is met when the acoustic wave frequency is the center frequency of the Bragg bandwidth, the calculation formula for the diffraction efficiency can be expressed by the following relationship (3):

[0104] Wherein, L is the length of the effective region where the acousto-optic effect occurs in the acousto-optic interaction medium 1241 along the direction of the incident light beam, H is the length of the effective region where the acousto-optic effect occurs in the acousto-optic interaction medium 1241 along the direction perpendicular to the plane formed by the incident light beam and the diffracted light beam, λ is the wavelength of the diffracted light beam, M2 is the acousto-optic figure of merit of the acousto-optic interaction medium 1241, and I is the sound wave power. If The calculation formula of diffraction efficiency η can be simplified as equation (4):

[0105] It can be seen that the diffraction efficiency η and the corresponding applied acoustic wave power value have a periodic function relationship, and the energy value of the deflected sensing light beam and the corresponding applied acoustic wave power value also have a corresponding periodic function relationship. In practical applications, due to the divergence angle of the incident light beam itself, the diffraction efficiency η will not reach the theoretical maximum value. When the acoustic wave frequency is not at the center frequency of the Bragg bandwidth, due to the momentum mismatch between the incident light beam vector, the outgoing diffracted light beam vector and the acoustic wave vector, the actual maximum value of the diffraction efficiency will also decrease as the momentum mismatch increases, but the overall change pattern can still be regarded as approximately satisfying the change relationship of the periodic function mentioned above. Therefore, the change of the diffraction efficiency η with the acoustic wave power I when the acoustic wave frequency is the center frequency of the Bragg bandwidth can be used as a basis for qualitatively judging the change of the diffraction efficiency η with the acoustic wave power I at different acoustic wave frequencies.

[0106] Taking the acoustic wave frequency at the center frequency of the Bragg bandwidth as an example, if the theoretical maximum value of the diffraction efficiency is 100% when the maximum sensing beam emission energy is reached, the corresponding applied acoustic wave power I must meet Let the applied acoustic power I be 1. Table 1 below shows the acoustic power I required to achieve diffraction efficiencies η of 50%, 10%, and 1% of the theoretical maximum, respectively:

[0107] Table 1

[0108] As can be seen from the above, the emission energy of the sensing light beam can be reduced to 1% of the maximum emission energy by adjusting the acoustic wave power to 0.4% of the acoustic wave power I applied when the maximum diffraction efficiency η is obtained.

[0109] Since the diffraction efficiency η and the corresponding applied acoustic wave power have a periodic functional relationship, a higher acoustic wave power can also be used to obtain the same diffraction efficiency η, as shown in Table 2 below:

[0110] Table 2

[0111] As can be seen from the above, the emission energy of the sensing beam can also be reduced to 1% of the maximum emission energy by adjusting the acoustic wave power to approximately 4 times the acoustic wave power I applied when obtaining the highest diffraction efficiency η. In this case, the sensitivity of the diffraction efficiency η to changes in the acoustic wave power is improved, which is conducive to more accurately adjusting the emission energy of the sensing beam by changing the acoustic wave power.

[0112] According to the above analysis, the emission energy adjustment unit 189 can adjust the energy of the light beam emitted after being deflected by at least one of the acousto-optic deflection modules 124 by changing the applied acoustic wave power, thereby adjusting the energy of the sensing light beam emitted by the entire emission module 12. Since the diffraction efficiency η and the corresponding acoustic wave power value have a periodic functional change relationship as shown in the relationship (4), the emission energy adjustment unit 189 can select multiple different acoustic wave power value adjustment intervals according to actual conditions to adjust the emission energy of the sensing light beam. In actual applications, the acoustic wave power required to be applied for different emission energies of the sensing light beam can be determined through pre-shipment testing and calibration.

[0113] It should be understood that the transmission energy adjustment unit 189 may include at least a driving circuit of the acoustic wave generator 1242 to control the acoustic wave power applied to the acousto-optic deflection module 124 .

[0114] It should be understood that the adjustment time of the acousto-optic deflection control unit 184 to adjust the deflection angle of the sensing beam by changing the frequency of the sound wave and the adjustment time of the emission energy adjustment unit 189 to adjust the emission energy of the sensing beam by changing the power of the sound wave are both approximately equal to the transit time τ of the sound wave in the acousto-optic interaction medium 1241. Therefore, when controlling the sensing beam to scan, the acousto-optic deflection control unit 184 and the emission energy adjustment unit 189 can synchronously change the frequency and power of the sound wave signal applied to the acousto-optic deflection module 124 to adjust the emission energy of the sensing beam while correspondingly changing the deflection angle of the sensing beam.

[0115] In some examples, the emission energy adjustment unit 189 may also adjust the emission energy of the sensing light beam by changing the light emitting power of the light source module 122. For example, the emission energy adjustment unit 189 adjusts the light emitting power of the light emitting unit 1220 of the light source module 122 by adjusting the driving current or driving voltage thereof.

[0116] In some embodiments, the emission energy adjustment unit 189 is configured to adjust the emission energy of the sensing beam by simultaneously changing the acoustic wave power and the luminous power of the light source module 122. In this case, compared to using only one method to adjust the emission energy of the sensing beam, using two different methods to simultaneously adjust the emission energy of the sensing beam can increase the adjustment range of the emission energy of the sensing beam, or reduce the difficulty of adjusting the emission energy. For example, each adjustment method only requires a smaller adjustment range to achieve a more significant adjustment of the emission energy, and the smaller the adjustment range, the easier it is to achieve.

[0117] In some embodiments, the maximum distance detection values ​​that the photoelectric detection device 10 needs to meet at different angles within the detection range may vary. For example, when the photoelectric detection device 10 is used as the main laser radar of a car, the maximum distance detection value required for the central angle of the detection range is higher, while the maximum distance detection value required for the edge angle of the detection range is relatively lower. The maximum distance detection value that needs to be met is generally positively correlated with the energy of the sensing light beam that needs to be emitted. Correspondingly, the emission energy adjustment unit 189 adjusts the applied acoustic wave power to increase the emission energy of the sensing light beam when the sensing light beam is deflected to the central angle of the detection range, and adjusts the applied acoustic wave power to reduce the emission energy of the sensing light beam when the sensing light beam is deflected to the edge angle of the detection range, so as to minimize the potential safety risks brought by the high-energy sensing light beam while meeting the different maximum distance detection value requirements within the detection range.

[0118] In some embodiments, as shown in FIG6 , the transmitting module 12 includes two separate acousto-optic deflection modules, namely a first acousto-optic deflection module 124a and a second acousto-optic deflection module 124b. The first acousto-optic deflection module 124a is configured to deflect the light beam passing through the first acousto-optic deflection module 124a in a first direction within a preset deflection angle range, and the second acousto-optic deflection module 124b is configured to deflect the light beam deflected by the first acousto-optic deflection module 124a in a second direction within a preset deflection angle range, wherein the second direction is different from the first direction. Thus, the light beam emitted by the light source module 122 is deflected by the first acousto-optic deflection module 124a and the second acousto-optic deflection module 124b respectively to form a sensing light beam that performs a two-dimensional scanning of the detection range. Optionally, the first direction can be a horizontal direction and the second direction can be a vertical direction; or, the first direction is a vertical direction and the second direction is a horizontal direction.

[0119] It should be understood that the second acousto-optic deflection module 124b can be arranged adjacent to the light-emitting side of the first acousto-optic deflection module 124a, or can be separated from the first acousto-optic deflection module 124a by several other optical path components, and this application does not impose any specific limitation on this.

[0120] In this case, the emission energy adjustment unit 189 is connected to the first acousto-optic deflection module 124a and the second acousto-optic deflection module 124b, respectively. By changing the first acoustic wave power applied to the first acousto-optic deflection module 124a and the second acoustic wave power applied to the second acousto-optic deflection module 124b, the diffraction efficiency of the first acousto-optic deflection module 124a and the second acousto-optic deflection module 124b on the passing light beam is correspondingly adjusted, thereby adjusting the energy of the sensing light beam emitted by the entire emission module 12. According to the above qualitative analysis, if the theoretical maximum value of the diffraction efficiency is 100% when the maximum sensing light beam emission energy is reached, the same acoustic wave power I is applied to the first acousto-optic deflection module 124a and the second acousto-optic deflection module 124b, satisfying Assuming the applied acoustic wave power I is 1, Table 3 below shows the corresponding applied acoustic wave power I when the first diffraction efficiency η1 of the first acousto-optic deflection module 124a and the second diffraction efficiency η2 of the second acousto-optic deflection module 124b are 50%, 10%, and 1% of the theoretical maximum values, respectively:

[0121] Table 3

[0122] As can be seen from the above, it is only necessary to reduce the diffraction efficiency of a single acousto-optic deflection module to 10% in order to achieve a sensing light beam emission of as low as 1% of the maximum emission energy for the entire emission module, which reduces the design difficulty of the emission energy adjustment unit for adjusting the acoustic wave power. On the other hand, by reducing the diffraction efficiency of each acousto-optic deflection module to 1%, the entire emission module can achieve a high-precision control of the sensing light beam emission energy at the level of 0.01%. It should be understood that in other embodiments, the emission module 12 may also include more than two acousto-optic deflection modules 124, so as to achieve the deflection of the sensing light beam within the detection range through these acousto-optic deflection modules 124. The emission energy adjustment unit 189 can also adjust the energy of the sensing light beam emitted by the entire emission module 12 by changing the acoustic wave power applied to any one or each of the acousto-optic modules 124.

[0123] For sensing a scanning angle within the detection range, the emission energy adjustment unit 189 can adjust the multiple first sensing beam pulses emitted first within a partitioned detection period to have a lower first emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules 124. The acoustic wave power applied to at least one of the acousto-optic deflection modules 124 can then be changed based on the analysis of the first sensing beam pulse echoes by the processing module 15 to adjust the emission energy of multiple second sensing beam pulses emitted later within the same partitioned detection period. It should be understood that the first emission energy can be set based on relevant safety standards that the photoelectric detection device 10 must meet when performing close-range detection. For example, the close range can refer to one-fifth, one-tenth, one-twentieth, one-thirtieth, etc. of the maximum distance detection value that the current scanning angle of the sensing beam must meet, or it can also be a distance value related to the actual usage scenario, such as 2 meters, 3 meters, 5 meters, 8 meters, 10 meters, etc.

[0124] In some embodiments, if the analysis of the first sensing beam pulse echo shows that there is an object within a preset maximum safety distance, the transmitting module 12 stops emitting the sensing beam pulse, and the processing module 15 directly outputs the analysis result of the first sensing beam pulse echo as the sensing result of the current partition detection period. The analysis result may include but is not limited to the distance information of the object and the reflectivity of the object.

[0125] If analysis of the first sensing beam pulse echo indicates that no object exists within the preset maximum safety distance, the emission energy adjustment unit 189 adjusts the acoustic wave power applied to at least one of the acousto-optic deflection modules 124 to adjust multiple second sensing beam pulses emitted later within the same sub-area detection period to have a higher second emission energy, i.e., the second emission energy is greater than the first emission energy. Alternatively, the second emission energy can be equal to or greater than the maximum emission energy required for the sensing beam pulse to meet the maximum distance detection value along the current scanning angle; alternatively, the second emission energy can be less than the maximum emission energy, with the appropriate emission energy determined based on object distance information obtained from analysis of the first sensing beam pulse echo. After emitting the second sensing beam pulse, the processing module 15 obtains sensing results for the current sub-area detection period, such as object distance information and reflectivity, based on analysis of the second sensing beam pulse echo.

[0126] It should be understood that the absence of an object within the preset maximum safety distance may mean that the analysis result of the first sensing beam pulse echo is that the first sensing beam pulse echo is not sensed or the object distance information obtained based on the sensed first sensing beam pulse echo is greater than the maximum safety distance.

[0127] It should be understood that the preset maximum safety distance can be defined as the shortest distance at which relevant safety standards can be met when the sensing beam is emitted at the highest emission energy. That is, if the distance between a person and the emission module 12 is equal to or greater than the maximum safety distance, even if the emission module 12 emits a sensing beam at the highest emission energy for scanning sensing, the person can still meet relevant safety standards without causing harm.

[0128] In some embodiments, if analysis of the first sensing beam pulse echo indicates the presence of an object within a preset maximum safety distance, the emission energy adjustment unit 189 can maintain the acoustic wave power applied to the acousto-optic deflection module 124 so that multiple second sensing beam pulses emitted later within the same partitioned detection period still have a lower first emission energy. After emitting the second sensing beam pulse, the processing module 15 obtains sensing results for the current partitioned detection period, such as object distance information and reflectivity, based on analysis of the first and second sensing beam pulse echoes. By integrating the echoes generated by the later-emitted second sensing beam pulse with the earlier-emitted first sensing beam pulse, the short-range detection performance of the photoelectric detection device 10 can be improved, for example, by improving dynamic range and accuracy, while maintaining a lower first emission energy while also meeting relevant safety standards.

[0129] In some embodiments, if analysis of the first sensing beam pulse echo indicates the presence of an object within a preset maximum safety distance, the emission energy adjustment unit 189 may adjust the acoustic power applied to at least one of the acousto-optic deflection modules 124 to adjust multiple second sensing beam pulses emitted later within the same sub-area detection period to have a third emission energy. This third emission energy is positively correlated with the object distance determined by the processing module 15 from the analysis of the first sensing beam pulse echo, and does not exceed the relevant safety standards required at that object distance. It should be understood that because the object distance is less than the maximum safety distance, the third emission energy is also less than the maximum emission energy required to meet the maximum distance detection value for the current scanning angle, but may be greater than the first emission energy. After emitting the second sensing beam pulse, the processing module 15 may obtain the sensing result for the current sub-area detection period based on the analysis of the second sensing beam pulse echo; alternatively, the processing module 15 may obtain the sensing result for the current sub-area detection period based on the analysis of the second sensing beam pulse echo and the first sensing beam pulse echo. Therefore, even if there is an object within the maximum safety distance, the transmission energy emitted in the latter part of the partition detection period can be reasonably adjusted according to the actual distance of the object, thereby improving the sensing quality as much as possible while meeting relevant safety standards.

[0130] In some embodiments, the photoelectric detection device 10 or the electronic device 1 equipped with the photoelectric detection device 10 may further include at least one speed sensor to sense the movement speed of the electronic device 1 or the photoelectric detection device 10. The emission energy adjustment unit 189 is configured to, if the movement speed of the photoelectric detection device 10 exceeds a preset speed threshold, change the acoustic wave power applied to at least one of the acousto-optic deflection modules 124 to emit multiple second sensing beam pulses with a higher second emission energy, without having to first emit a lower energy first sensing beam pulse for detection within a partitioned detection period. The second emission energy may be equal to or greater than the maximum emission energy required for the sensing beam pulse to meet the maximum distance detection value along the current scanning angle. Since the photoelectric detection device 10 is moving rapidly, even if there is a person within the maximum safety distance, the duration of the emitted sensing beam pulse irradiating the person is greatly reduced. Therefore, even if the sensing beam pulse is emitted at the highest emission energy, it can still meet relevant safety standards. Emitting the sensing beam pulse at the highest emission energy is beneficial to improving the quality of sensing.

[0131] It should be understood that if the moving speed of the photoelectric detection device 10 is less than or equal to a preset speed threshold, the emission energy adjustment unit 189 can first emit a first sensing light beam pulse with lower energy within a partition detection period in accordance with the technical solution recorded in the aforementioned embodiment, and then change the acoustic wave power applied to at least one of the acousto-optic deflection modules 124 based on the analysis of the sensed first sensing light beam pulse echo by the processing module 15 to adjust the emission energy of multiple second sensing light beam pulses emitted later within the same partition detection period.

[0132] In some embodiments, all or part of the functional units in the control module 18 and / or the processing module 15 may include firmware solidified in the storage medium 30 or computer software code stored in the storage medium 30, and executed by one or more corresponding processors 40 to control related components to implement corresponding functions. The processor 40 is, for example, but not limited to, an application processor (AP), a central processing unit (CPU), a microcontroller unit (MCU), etc. The storage medium 30 includes, but is not limited to, flash memory, electrically erasable programmable read only memory (EEPROM), programmable read only memory (PROM), a hard disk, etc.

[0133] In some embodiments, the processor 40 and / or the storage medium 30 may be disposed within the photoelectric detection device 10, for example, integrated on the same circuit board as the transmitting module 12 or the receiving module 14. Alternatively, in other embodiments, the processor 40 and / or the storage medium 30 may be disposed at other locations within the electronic device 1, for example, on a main circuit board of the electronic device 1.

[0134] In some embodiments, part or all of the functional units of the control module 18 and / or the processing module 15 may also include hardware, for example, implemented by any one of the following technologies or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing logical functions on data signals, a dedicated integrated circuit having a suitable combinational logic gate circuit, a programmable gate array (PGA), a field programmable gate array (FPGA), a driving circuit for a specific object, etc.

[0135] It can be understood that different functional units of the control module 18 and / or part of the processing module 15 can respectively include the same hardware, for example: the acousto-optic deflection control unit 184 and the emission energy adjustment unit 189 can both include the driving circuit of the sound wave generator 1242.

[0136] It is understandable that the hardware for implementing the functions of the control module 18 and / or the processing module 15 can be disposed within the photoelectric detection device 10. The hardware for implementing the functions of the control module 18 and / or the processing module 15 can also be disposed at other locations of the electronic device 1, such as on a main circuit board of the electronic device 1.

[0137] As shown in Figure 8, in some embodiments, the photoelectric detection device 10 is, for example, a laser radar, and the electronic device 1 is, for example, a car. The laser radar can be installed at multiple locations on the car to detect distance information of objects within the car's surroundings and implement driving control accordingly.

[0138] Compared with laser radars that use mechanical rotation and hybrid solid-state methods to achieve sensing beam scanning, the laser radar provided in this application uses a purely solid-state acousto-optic deflection module 124 and a secondary deflection module 126 to achieve deflection scanning of the sensing beam. Since it no longer needs to rely on rotating or vibrating components, it has higher reliability and a more compact structure, is easier to pass strict vehicle regulations, and has less impact on the appearance of the car.

[0139] It should be noted that the technical solution to be protected by this application may satisfy only one of the above embodiments or multiple embodiments at the same time. That is to say, the embodiment composed of one or more of the above embodiments also falls within the scope of protection of this application.

[0140] Throughout this specification, reference to terms such as "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" 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, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0141] It should be understood that the various parts of the embodiments of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above-mentioned embodiments, multiple functional units can be implemented using software or firmware stored in a storage medium and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used to implement: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0142] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. An emission module based on the acousto-optic effect, characterized in that, configured to emit a sensing beam for three-dimensional information detection based on the time-of-flight principle to a detection range, comprising: a light source module configured to emit a light beam; at least one acousto-optic deflection module, comprising an acousto-optic interaction medium and an acoustic wave generator, the acoustic wave generator being configured to generate an acoustic wave propagating in a preset direction in the acousto-optic interaction medium; and a control module, comprising an acousto-optic deflection control unit and a transmission energy adjustment unit, the acousto-optic deflection control unit being configured to deflect the light beam passing through the acousto-optic interaction medium by a plurality of different preset deflection angles within a preset deflection angle range by controlling the acoustic wave frequency applied by the acoustic wave generator as a sensing beam for scanning the detection range, the transmission energy adjustment unit being configured to correspondingly adjust the energy of the sensing beam by changing the acoustic wave power applied by the acoustic wave generator.

2. The emission module according to claim 1, wherein The sensing beam is the first-order diffracted light of the light beam diffracted by the acousto-optic interaction medium.

3. The emission module according to claim 1, wherein There is a variation relationship of a periodic function between the energy value of the sensing beam and the corresponding acoustic wave power value.

4. The emission module according to claim 1, wherein The transmission energy adjustment unit is configured to correspondingly adjust the emission energy of the sensing beam by simultaneously changing the light emission power of the light source module.

5. The emission module according to claim 1, wherein Comprising two discrete acousto-optic deflection modules, namely a first acousto-optic deflection module and a second acousto-optic deflection module, the first acousto-optic deflection module being configured to deflect the passing light beam by a plurality of different preset deflection angles along a first direction within a preset deflection angle range, the second acousto-optic deflection module being configured to deflect the passing light beam by a plurality of different preset deflection angles along a second direction different from the first direction within a preset deflection angle range, the light beam emitted by the light source module forms a sensing beam for two-dimensional scanning of the detection range after being deflected by the first acousto-optic deflection module and the second acousto-optic deflection module respectively, and the transmission energy adjustment unit adjusts the energy of the sensing beam by controlling the acoustic wave power applied to at least one of the acousto-optic deflection modules.

6. The emission module according to claim 1, wherein Further comprising an electro-optic deflection module, the acousto-optic deflection module being configured to deflect the passing light beam by a plurality of different preset deflection angles along a first direction within a preset deflection angle range, the electro-optic deflection module being configured to deflect the passing light beam by a plurality of different preset deflection angles along a second direction different from the first direction within a preset deflection angle range according to the applied electric field strength, the light beam emitted by the light source module forms a sensing beam for two-dimensional scanning of the detection range after being deflected by the acousto-optic deflection module and the electro-optic deflection module respectively, and the control module adjusts the energy of the sensing beam by controlling the acoustic wave power applied to the acousto-optic deflection module.

7. The emission module according to claim 5 or 6, characterized in that The first direction is the horizontal direction and the second direction is the vertical direction; or, The first direction is the vertical direction and the second direction is the horizontal direction.

8. An optoelectronic detection device, characterized in that, configured to perform distance detection on an object located within a preset detection range, the optoelectronic detection device includes a transmitting module as described in any one of claims 1-7, the optoelectronic detection device further includes a receiving module and a processing module, the receiving module is configured to sense an optical signal from within the detection range and output a corresponding optical induction signal, and the processing module is configured to analyze and process the optical induction signal to perform distance detection within the detection range.

9. The optoelectronic detection device according to claim 8, wherein During the same partition detection period for performing distance detection on a corresponding partition along a preset scanning angle within the detection range, the emission energy adjustment unit controls the acoustic wave power applied to at least one of the acousto-optic deflection modules to adjust a plurality of first sensing beam pulses emitted first during the partition detection period to have a lower first emission energy, and then controls the acoustic wave power applied to at least one of the acousto-optic deflection modules according to the analysis of the echo of the first sensing beam pulses sensed by the processing module to adjust the emission energy of a plurality of second sensing beam pulses emitted later during the partition detection period.

10. The optoelectronic detection device according to claim 9, wherein, If the analysis of the echo of the first sensing beam pulses shows that there is no object within the preset maximum safety distance, the emission energy adjustment unit adjusts a plurality of second sensing beam pulses emitted later during the partition detection period to have a higher second emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules, and the processing module obtains the sensing result of the current partition detection period according to the analysis of the echo of the second sensing beam pulses.

11. The optoelectronic detection device according to claim 10, characterized in that, The second emission energy is equal to or greater than the highest emission energy required for the distance detection farthest value that the sensing beam pulse needs to satisfy along the current scanning angle; or, The second emission energy is less than the highest emission energy, and the appropriate emission energy is determined according to the object distance information obtained from the analysis of the echo of the first sensing beam pulses.

12. The optoelectronic detection device according to claim 9, wherein, If the analysis of the echo of the first sensing beam pulses shows that there is an object within the preset maximum safety distance, the transmitting module stops emitting the sensing beam pulses, and the processing module directly outputs the analysis result of the echo of the first sensing beam pulses as the sensing result of the current partition detection period.

13. The optoelectronic detection device according to claim 9, characterized in that, If the analysis of the echo of the first sensing beam pulses shows that there is an object within the preset maximum safety distance, the emission energy adjustment unit can maintain the acoustic wave power applied to the acousto-optic deflection module so that a plurality of second sensing beam pulses emitted later during the partition detection period still have the lower first emission energy, and the processing module obtains the sensing result of the current partition detection period according to the analysis of the echo of the first sensing beam pulses and the echo of the second sensing beam pulses.

14. The optoelectronic detection device according to claim 9, characterized in that, If the analysis of the first sensed beam pulse echo shows that there is an object within a preset maximum safety distance, the emission energy adjustment unit adjusts the acoustic wave power applied to at least one of the acousto-optic deflection modules to adjust multiple second sensed beam pulses emitted later within the same partition detection period to have a third emission energy, and the third emission energy is positively correlated with the object distance obtained by the processing module's analysis of the first sensed beam pulse echo, and does not exceed the relevant safety standards that should be met at that object distance at most.

15. The optoelectronic detection device according to claim 8, characterized in that, The emission energy adjustment unit is configured to, if the moving speed of the photoelectric detection device exceeds a preset speed threshold, emit multiple second sensed beam pulses with a second emission energy by changing the acoustic wave power applied to at least one of the acousto-optic deflection modules, and the second emission energy is equal to or greater than the highest emission energy required for the sensed beam pulse to meet the farthest distance detection value along the current scanning angle.

16. An electronic device, characterized in that, Including the photoelectric detection device according to claims 8-15, the electronic device further includes an application module, and the application module is configured to implement corresponding functions according to the detection results of the photoelectric detection device.

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