Optical detection devices and electronic equipment

Abstract

The present application discloses an optical detection device, which includes a transmitting module, a receiving module, a processing module and a control module. The transmitting module is used to transmit an optical signal. The receiving module is used to receive the optical signal and output a corresponding sensing signal. The processing module is used to count and count the sensing signals generated by the receiving module in different time bins of a receiving cycle to form a statistical histogram. The control module is used to adjust the optical transmission power of the optical signal emitted by the transmitting module according to the ambient light information obtained from the statistical histogram. The present application also discloses an electronic device including the optical detection device.

Description

Technical Field

[0001] The present application relates to the field of photoelectric sensing technology, and more specifically, to optical detection devices and electronic devices. Background Art

[0002] The principle of Time of Flight (TOF) measurement is to calculate the distance of an object, or depth, by measuring the flight time of a light signal in space. Due to its advantages such as long sensing distance, high accuracy and low energy consumption, it is widely used in consumer electronics, unmanned driving, AR / VR and other fields.

[0003] The optical detection device using the TOF principle includes a transmitting module and a receiving module. The transmitting module is used to transmit a light signal into space. The receiving module is used to receive the light signal returned from the object and calculate the distance of the object based on the time required from the transmission to the reception of the light signal.

[0004] However, in order to distinguish the sensing light signal returned by the object from the background noise caused by the ambient light, it is often necessary to let the transmitting module transmit the light signal to the space at a higher transmission power to ensure that enough sensing light signals returned from the object can be received even under relatively harsh ambient light conditions. Therefore, the transmitting module needs to maintain a higher level of light transmission power during operation, which will increase the overall power consumption of the TOF device on the one hand, and shorten the device life of the transmitting module on the other hand. Summary of the invention

[0005] In view of this, the present invention provides an optical detection device and an electronic device that can improve the problems of the prior art.

[0006] The embodiment of the present application provides an optical detection device, which includes a transmitting module, a receiving module, a processing module and a control module. The transmitting module is used to transmit a light signal. The receiving module is used to receive the light signal and output a corresponding sensing signal. The processing module is used to count and count the sensing signals generated by the receiving module in different time bins of a receiving cycle to form a statistical histogram. The control module is used to adjust the optical transmission power of the optical signal emitted by the transmitting module according to the ambient light information obtained from the statistical histogram.

[0007] In an embodiment of the present invention, the sensing signal count generated by the photons of ambient light received by the receiving module forms the noise background in the statistical histogram, and a portion of the light signal emitted by the transmitting module is reflected back by an object in space to form a sensing light signal. The sensing signal count generated by the photons of the sensing light signal received by the receiving module is superimposed on the noise background to form a signal peak where the sensing signal count is higher than the sensing signal count of the adjacent time bin, and the light signal emitted by the transmitting module at the light transmitting power P in the preset time window t w The average value N of the sensing signal count of the sensing light signal generated within s Satisfies the relationship (1): Where A is a fixed coefficient, P is the optical power of the optical signal, γ is the reflectivity of the object, h represents Planck's constant, c represents the speed of light, λ represents the wavelength of light, M represents the number of light pixels used by the receiving module for sensing, D is the lens entrance pupil radius, d represents the distance of the object, θ1 is the lens transmittance, θ f is the filter transmittance, ε represents the probability of photon-triggered avalanche of the photosensitive pixel, FF represents the fill factor, and N is the number of light signal emissions in a detection frame.

[0008] In the embodiment of the present invention, the object reflectivity γ has a value ranging from 10% to 90%.

[0009] In an embodiment of the present invention, the optical transmission power P of the optical signal transmitted by the transmitting module is adjusted according to the relation (1) so that the N in the statistical histogram formed is s Satisfies the relationship (2): Among them, α is the confidence factor, which represents the credibility of the signal peak being higher than the noise background, σ s+n is the preset time window t w The standard deviation of the sensing signal counts generated by the photons of the internal ambient light and the photons of the sensing light signal, σ n is the preset time window t w The standard deviation of the sensing signal counts generated by the photons of the internal ambient light, N n is the preset time window t w The average value of the sensing signal counts generated by the photons of ambient light sensed within, N n As ambient light information is obtained through the statistical histogram, the control module includes a power calculation unit, which is used to determine the light emission power value range adapted to the ambient light information of the current scene according to the above-mentioned relationship (1), relationship (2) and the statistical histogram, and the power adjustment unit adjusts the light emission power of the light-emitting unit according to the adapted light emission power value range determined by the power calculation unit.

[0010] In an embodiment of the present invention, the confidence factor α can be adjusted according to the application scenario, and the power calculation unit determines the range of light emission power values ​​that are compatible with the ambient light information of the current scene and the confidence factor α based on the adjusted relationship (1), relationship (2) and the statistical histogram.

[0011] In an embodiment of the present invention, the optical detection device is preset with a total value threshold range, and the control module includes a comparison unit, which compares the actual total value of all time bins in the statistical histogram with the preset total value threshold range. If the actual total value is greater than the maximum value of the preset total value threshold range, the power adjustment unit reduces the optical transmission power of the transmission module; if the actual total value is lower than the minimum value of the preset total value threshold range, the optical transmission power of the transmission module is increased by the power adjustment unit; if the actual total value is within the preset total value threshold range, there is no need to adjust the optical transmission power.

[0012] In an embodiment of the present invention, the optical detection device is preset with a total value threshold range, the control module includes a comparison unit, the comparison unit compares the actual total value of all time bins in the statistical histogram with the preset total value threshold range, the control module controls the emission module to continuously emit multiple optical signals with a first optical emission power as a first group of optical signals, and continuously emit multiple optical signals with a second optical emission power as a second group of optical signals, and the first optical emission power is greater than the second optical emission power. The comparison unit compares the first actual total value measured corresponding to the first group of optical signals and the second actual total value measured corresponding to the second group of optical signals with the preset total value threshold range, and the power adjustment unit selects the optical emission power adapted to the current ambient light information according to the above comparison results.

[0013] In an embodiment of the present invention, the power adjustment unit selects the first optical transmit power or the second optical transmit power corresponding to the first actual total value or the second actual total value within a preset total value threshold range as the adapted optical transmit power.

[0014] In an embodiment of the present invention, if the first actual total value and the second actual total value are both within a preset total value threshold range, the power adjustment unit selects the optical transmission power corresponding to the first actual total value and the second actual total value that is closest to the middle value of the total value threshold range as the adapted optical transmission power.

[0015] In an embodiment of the present invention, if the first actual total value and the second actual total value are both within a preset total value threshold range, the power adjustment unit selects a smaller second optical transmit power as the adapted optical transmit power.

[0016] In an embodiment of the present invention, a portion of the light signal emitted by the transmitting module is reflected back by an object in space to form a sensing light signal, and the processing module is also used to obtain the flight time corresponding to the sensing light signal through a statistical histogram to calculate relevant sensing information of the object.

[0017] The embodiment of the present application provides an electronic device, which includes the optical detection device as described in the above embodiment. The electronic device may also include an application module, which is used to implement corresponding functions according to the sensing information obtained by the optical detection device.

[0018] The optical detection device of the present application can adjust the light emission power of the transmitting module according to the ambient light conditions in the scene, so that the emission power of the optical signal can be appropriately reduced in the scene with weak ambient light, thereby reducing the power consumption of the optical detection device, increasing the life of the light source, and improving the stability of the entire system.

[0019] Additional aspects and advantages of the embodiments of the present application will be given in the following description, and in part will become apparent from the following description, or will be understood through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of functional modules of an optical detection device provided by an embodiment of the present application applied to an electronic device;

[0021] Figure 2 yes Figure 1 A schematic diagram of functional modules of the optical detection device;

[0022] Figure 3 is a schematic diagram of the relationship between different signals of the optical detection device provided in an embodiment of the present application;

[0023] Figure 4 is a schematic diagram of functional modules of an optical device provided by another embodiment of the present application applied to an electronic device;

[0024] Figure 5 is a statistical histogram of a sensing signal of the optical detection device provided in an embodiment of the present application;

[0025] Figure 6 yes Figure 5 Schematic diagram of the relationship between the signal peak fluctuation and the noise background fluctuation;

[0026] Figure 7 is a schematic diagram of a signal peak that satisfies a Gaussian distribution in a statistical histogram of an optical detection device provided in an embodiment of the present application;

[0027] Figure 8is a schematic diagram of a signal peak showing an avalanche pile-up effect in a statistical histogram of an optical detection device provided in an embodiment of the present application;

[0028] Fig. 9 It is a schematic diagram of functional modules of an optical detection device provided in another embodiment of the present application. Specific embodiments

[0029] In the specific description of the embodiments of the present application, it should be understood that when a substrate, sheet, layer or pattern is referred to as being "on" or "under" another substrate, another sheet, another layer or another pattern, it may be "directly" or "indirectly" on another substrate, another sheet, another layer or another pattern, or one or more intermediate layers may also exist. For the purpose of clarity, the thickness and size of each layer in the drawings of the specification may be exaggerated, omitted or schematically indicated. In addition, the size of the elements in the drawings does not fully reflect the actual size.

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0031] The disclosure below provides many different embodiments or examples to implement different structures of the present application. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0032] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

[0033] The features of "one", "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0034] Further, described features, structures can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that, without one or more of the specific details, or adopting other structures, components, etc., it is also possible to put the technical scheme of the present application into practice. In other cases, known structures or operations are not shown or described in detail to avoid blurring the present application.

[0035] An embodiment of the present application provides an optical detection device, which includes a transmitting module, a receiving module, a processing module and a control module. The transmitting module is used to transmit an optical signal. The receiving module is used to receive the optical signal and output a corresponding sensing signal. The processing module is used to count and count the sensing signals generated by the receiving module in different time bins of a receiving cycle to form a statistical histogram. The control module is used to adjust the optical transmission power of the optical signal emitted by the transmitting module according to the ambient light information obtained from the statistical histogram.

[0036] Optionally, the optical detection device can detect relevant information based on the time-of-flight principle. The transmitting module and the receiving module are arranged side by side and adjacent to each other, and the distance between the transmitting module and the receiving module can range from 2 millimeters (mm) to 20 mm, for example. It can be understood that in some embodiments, the signals emitted by the transmitting module and received by the receiving module are both optical signals, and the distance between the transmitting module and the receiving module refers to the distance between the optical axes of their respective optical systems. The transmitting module includes a light emitting surface for emitting light signals, and the receiving module includes a light incident surface for receiving light signals. When the transmitting module and the receiving module are arranged side by side, the light emitting surface of the transmitting module and the light incident surface of the receiving module face the same side of the optical detection device.

[0037] Optionally, in some embodiments, the transmitting module transmits a light signal into space to detect relevant sensing information of an object in space, such as but not limited to: a combination of one or more of the depth information, distance information, proximity information, etc. of the object. The light signal may be, for example, a light pulse with a preset frequency. At least part of the emitted light signal is reflected by an object in space and returned to form a sensing light signal. The processing module is also used to obtain the flight time corresponding to the sensing light signal through a statistical histogram to calculate the relevant sensing information of the object.

[0038] Optionally, the sensing signal may be an electrical signal. Alternatively, the sensing signal may be other signals, such as a magnetic signal, depending on the photon conversion principle of the receiving module.

[0039] Optionally, the optical signal received by the receiving module may include the sensing optical signal. The optical signal received by the receiving module may also include other optical signals not emitted by the transmitting module, such as photons in ambient light or optical signals emitted by other light sources in the scene except the transmitting module.

[0040] An embodiment of the present application also provides an electronic device, including the optical detection device. The electronic device implements the corresponding function based on the sensing information obtained by the optical detection device. The sensing information is, for example, a combination of one or more related information such as proximity information, depth information, and distance information of an object in space. Among them, the depth information can be used in 3D modeling, face recognition, automatic driving, machine vision, monitoring, drone control, augmented reality (AR) / virtual reality (VR), simultaneous localization and mapping (SLAM) and other fields, and the present application does not limit this. The proximity information is used, for example, to determine whether there is an object approaching. The optical detection device is, for example, a laser radar, which can be used to obtain depth information or distance information of objects in the scene to assist in realizing automatic driving control of the car.

[0041] Hereinafter, embodiments in which the optical detection device is applied to electronic equipment will be described in detail with reference to the accompanying drawings.

[0042] Figure 1 It is a schematic diagram of functional modules of the optical detection device 10 provided in an embodiment of the present application applied to an electronic device 1 . Figure 2 It is a schematic diagram of the functional modules of the optical detection device 10 provided in an embodiment of the present application.

[0043] Reference Figure 1 and Figure 2 , the electronic device 1 includes an optical detection device 10, which is used to measure the object 2 in the space using the principle of light flight time measurement to obtain corresponding information of the object 2, such as but not limited to: a combination of one or more of proximity information, depth information, and distance information. The electronic device 1 may also include an application module 20, which may implement related functions based on the corresponding sensing information of the object 2, such as but not limited to: judging whether the object 2 appears within a preset range in front of the electronic device 1 based on the proximity information of the object 2; or controlling the electronic device 1 to avoid obstacles based on the distance information of the object 2; or performing 3D modeling, face recognition, and realizing machine vision based on the depth information of the object 2.

[0044] Optionally, in some embodiments, the optical detection device 10 is, for example, a direct time of flight (DTOF) measurement device. The DTOF measurement device 10 can perform depth information sensing based on the direct time of flight detection principle. For example, the DTOF measurement device 10 can emit a light signal into space and receive a sensed light signal reflected by an object 2 in space. The time difference between the emission of the light signal and the reception of the sensed light signal is called the flight time t. The depth information or distance information of the object 2 is obtained by calculating the distance traveled by the light signal during the above-mentioned flight time. Where c is the speed of light.

[0045] Optionally, in some other embodiments, the optical detection device 10 may also be an indirect time of flight (ITOF) measurement device. The ITOF measurement device 10 performs depth information sensing based on the indirect time of flight detection principle. The ITOF measurement device 10 obtains the depth information of the object 2 by calculating the phase difference between the emitted light signal and the received sensing light signal.

[0046] In the following embodiments of the present application, the optical detection device 10 is mainly described as a DTOF measurement device as an example.

[0047] Optional, such as Figure 2 As shown, the optical detection device 10 includes a transmitting module 12, a receiving module 14, a processing module 15 and a control module 18. The transmitting module 12 is used to transmit a light signal into space, at least part of the transmitted light signal is reflected by an object 2 in the space to form a sensing light signal, at least part of the sensing light signal is received by the receiving module 14. The sensing light signal carries corresponding information of the object 2, such as depth information, distance information, proximity information, etc.

[0048] The emission module 12 includes a light emitting unit 120 and a modulation element 124. The light emitting unit 120 is used to emit a light signal. The modulation element 124 is used to modulate the light signal emitted by the light emitting unit 120 to form a light signal that can be used for sensing and project it into the space. Optionally, the light signal emitted by the emission module 12 is, for example but not limited to, a speckle pattern or a flood beam.

[0049] Optionally, in some embodiments, the modulation element 124 is, for example, a diffuser or a light homogenizer, which is used to homogenize the light signal emitted by the light-emitting unit 120 to form a floodlight beam.

[0050] Optionally, in some embodiments, the modulation element 124 is, for example, a diffractive optical element (DOE), which is used to replicate the light signal emitted by the light emitting unit 120 and expand and arrange it within a preset field of view angle range to form a speckle pattern. The speckle pattern can be regularly arranged, irregularly arranged, or randomly arranged.

[0051] By duplicating the light signal emitted by the light emitting unit 120 through the DOE, the light signal emitted to the object 2 is composed of a plurality of duplicated light signals, which is beneficial to expanding the field of view angle range of the optical detection device 10 and improving the sensing effect.

[0052] Optionally, in some embodiments, the modulation element 124 may be other suitable types of beam modulation elements, such as but not limited to a microlens array, etc., and the present application does not make any special limitation on this.

[0053] Optionally, in some embodiments, the transmitting module 12 may further include other suitable optical elements, for example, a lens (not shown) is provided on the path of the light signal emitted from the light emitting unit 120, and the lens may be provided between the light emitting unit 120 and the modulating element 124, and is used to collimate or converge the light signal emitted by the light emitting unit 120 before transmitting it to the modulating element 124. The lens may be a combination of multiple single lenses.

[0054] It should be understood that the embodiment of the present application does not specifically limit the wavelength range of the optical signal emitted by the light emitting unit 120. Optionally, the optical signal emitted by the light emitting unit 120 may be, for example, visible light, infrared light, near infrared light, ultraviolet light, etc.

[0055] Optionally, in some embodiments, the light emitting unit 120 may include a single light source or multiple light sources. The multiple light sources may be, for example, a light source array arranged regularly or irregularly. Figure 2 As shown, the light emitting unit 120 is a vertical cavity surface emitting laser (Vertical Cavity Surface Emitting Laser, VCSEL for short, also translated as vertical resonant cavity surface emitting laser), and the light emitting unit 120 may include a semiconductor substrate and a VCSEL array die composed of a plurality of VCSEL light sources arranged on the semiconductor substrate.

[0056] Optionally, in some embodiments, the light source of the light emitting unit 120 may be, for example, an edge emitting laser (EEL), a light emitting diode (LED), a laser diode (LD), etc. The edge emitting laser may be a Fabry Perot (FP) laser, a distributed feedback (DFB) laser, and an electro-absorption modulated laser (EML), which is not limited in the embodiments of the present application.

[0057] Optionally, in some embodiments, the light signal emitted by the light emitting unit 120 is infrared light or near-infrared light, and the wavelength range may be: 700nm to 2000nm, for example: 850nm, 905nm, 940nm, 1064nm, 1550nm, etc.

[0058] Optionally, in some embodiments, the receiving module 14 may include a photoelectric sensor 140. The photoelectric sensor 140, for example, includes a single photosensitive pixel 142 or a pixel array composed of a plurality of photosensitive pixels 142, and the pixel array is used to receive a sensing light signal reflected by the object 2 to obtain relevant sensing information, such as but not limited to the depth information of the object 2.

[0059] Optionally, in some embodiments, the photosensitive pixel 142 is, for example, a single photon avalanche diode (SPAD), an avalanche photodiode (APD), a photodiode and / or other suitable photoelectric conversion elements. For example, but not limited to, each photosensitive pixel 142 may include a single SPAD and / or a combination of multiple SPADs.

[0060] Optionally, in some embodiments, the receiving module 14 may further include a readout circuit (not shown) composed of one or more of a signal amplifier, a time-to-digital converter (TDC), an analog-to-digital converter (ADC), etc. connected to the photoelectric sensor 140. Optionally, the readout circuit may also be partially or fully integrated in the photoelectric sensor 140.

[0061] Optionally, the receiving module 14 may further include a lens unit 144, which may be used to receive a sensing light signal returned from the object 2, and collimate or converge the sensing light signal before transmitting it to the photosensitive pixel 142 on the photoelectric sensor 140. The lens unit 144 may be a combination of multiple single lenses.

[0062] Optionally, the optical detection device 10 can detect relevant information based on the time-of-flight principle. The transmitting module 12 and the receiving module 14 are arranged side by side and adjacent to each other, and the distance between the transmitting module 12 and the receiving module 14 can range from 2 millimeters (mm) to 20 mm, for example. It can be understood that in some embodiments, the transmitting module 12 transmits and the receiving module 14 receives both optical signals, and the distance between the transmitting module 12 and the receiving module 14 refers to the distance between the optical axes of their respective optical systems. The transmitting module 12 includes a light emitting surface for emitting light signals, and the receiving module 14 includes a light incident surface for receiving light signals. When the transmitting module 12 and the receiving module 14 are arranged side by side, the light emitting surface of the transmitting module 12 and the light incident surface of the receiving module 14 face the same side of the optical detection device 10.

[0063] Optionally, the control module 18 can be used to control the emission of the light emitting unit 120 in the emission module 12, for example, it can be used to control the frequency of the emitted light signal, the position of the light source lit at different times, the light power of the light source, etc. Optionally, in some embodiments, the control module 18 includes an emission control unit 180, and the emission control unit 180 is used to control the light emitting unit 120 to emit a light signal to space at a preset frequency, and the light signal is, for example, a light pulse with a preset frequency.

[0064] like Figure 3 As shown, in some embodiments, the emission control unit 180 can control the light emitting unit 120 to emit a light signal according to an emission control signal with a preset frequency. It can be understood that the emission control signal can be a drive signal applied to the drive circuit of the light emitting unit 120. Optionally, the emission control signal can be a series of control pulse signals, such as a square wave pulse signal. The control pulse signal includes alternating high-level segments and low-level segments. The light emitting unit 120 is controlled to continuously emit light into the space in the high-level segment and stop emitting light in the low-level segment, thereby emitting a corresponding light pulse as the light signal. Thus, within the timing corresponding to the high-level segment, the light emitting unit 120 continuously emits a light signal into the space, and at least part of the light signal can be reflected back from the object 2 in the space.

[0065] It is understandable that the frequency of the optical signal can be set according to the detection range of the optical detection device 10. For example, one emission cycle of the optical signal includes a light-emitting segment and an extinguishing segment, and the light-emitting unit 120 continuously emits the optical signal in the light-emitting segment and stops emitting light in the extinguishing segment. The emission cycle of the optical signal needs to be greater than the maximum flight time corresponding to the detection range, so that the optical signal emitted in one emission cycle can effectively detect the object 2 within the detection range.

[0066] Optionally, in some embodiments, part or all of the functional units of the control module 18 may be integrated into the transmitting module 12 .

[0067] Optionally, in some embodiments, the control module 18 may further include a receiving control unit 182. The receiving control unit 182 may be used to control the receiving module 14 to synchronously start receiving the optical signal at the start time of each emission cycle of the optical signal to sense the returned photons. Thus, the receiving module 14 has a receiving cycle corresponding to the emission cycle of the optical signal, the start time of the receiving cycle corresponds to the start time of the emission cycle, and the end time of the receiving cycle corresponds to the end time of the emission cycle. Optionally, in some embodiments, the start time of the receiving cycle is synchronized with the start time of the emission cycle, and the end time of the receiving cycle is synchronized with the end time of the emission cycle.

[0068] Specifically, in some embodiments, the receiving control unit 182 is used to control the photosensitive pixel 142 to synchronously start sensing photons at the start of each emission cycle of the light signal. The photosensitive pixel 142 is, for example, a SPAD, which can only sense a single photon in a receiving cycle. Once the SPAD is triggered by a single photon in a receiving cycle, an avalanche effect will be formed to generate a corresponding sensing signal, which is, for example, an electrical signal. The SPAD after the avalanche needs to be quenched and reset to restore the bias voltage to above the breakdown voltage so as to sense photons again in the next receiving cycle. Based on the above characteristics, the SPAD can sense a photon of the returned sensing light signal in a receiving cycle to generate a corresponding sensing signal. It is understandable that the SPAD may not be able to sense photons in a receiving cycle and does not generate a corresponding sensing signal, but regardless of whether the photon can be sensed, the SPAD will be reset before the end of a receiving cycle to restart sensing the received photons at the beginning of the next receiving cycle.

[0069] Optionally, in some embodiments, some or all of the functional units of the control module 18 may be integrated in the

[0070] In the receiving module 14.

[0071] Optionally, in some embodiments, the optical detection device 10 may further include a processing module 15. The processing module 15 is used, for example, to determine the depth information or distance information of the object 2 based on the time difference between the emission time of the light signal and the sensing time of the returned sensing light signal. However, it is not limited thereto. In other embodiments, the processing module 15 may also obtain relevant sensing information based on the received sensing light signal and other suitable detection principles. Optionally, as Figure 1 As shown, the processing module 15 can be integrated into the optical detection device 10. Alternatively, Figure 4 As shown, the processing module 15 may also be disposed at other locations in the electronic device 1 other than the optical detection device 10. For example, the processing module 15 may be a main control module of the electronic device 1, which is not limited in the present application. Figure 1 As shown, the light sensing sensor 16 can be integrated into the optical detection device 10. Alternatively, as Figure 4 As shown, the light sensing sensor 16 may also be disposed at other locations in the electronic device 1 except for the optical detection device 10 .

[0072] Please also read Figure 2 , 3 And 5. In some embodiments, the processing module 15 may include a timing unit 150, a counting unit 152 and a statistical unit 154. The timing unit 150 may divide the receiving cycle into a plurality of time bins starting from the starting moment, wherein each time bin corresponds to a preset time interval Δt. Optionally, the time intervals Δt corresponding to each time bin are respectively equal. Optionally, the time interval Δt may be the minimum time interval Δt that the TDC can distinguish. It is understandable that the time difference between each time bin and the starting moment of the receiving cycle may be used as a timestamp for the time bin. The timing unit 150 may also be used to calculate the time difference between the moment of the sensing signal generated by the optical signal received by the receiving module 14 within a receiving cycle and the starting moment of the receiving cycle, as a timestamp for the sensing signal.

[0073] Optionally, in some embodiments, the counting unit 152 may be used to perform cumulative counting in a time bin with a corresponding time bin according to the timestamp of the sensing signal, that is, to add one to the number of sensing signals with the same timestamp that have been counted in the time bin. It is understandable that, for an embodiment using SPAD as the photosensitive pixel 142, a photosensitive pixel 142 can only receive a single photon of the light signal and generate a corresponding sensing signal in each receiving cycle, thereby accumulating one in one of the many time bins, or failing to receive any photon and not generating a sensing signal, thereby not accumulating in any time bin.

[0074] It can be understood that the optical signal received by the receiving module 14 may include a sensing light signal emitted from the transmitting module 12 and reflected by an object in the space, and may also include other light signals not emitted by the transmitting module 12, for example: photons of ambient light or light signals emitted by other light sources in the scene except the transmitting module 12.

[0075] Optionally, in some embodiments, the statistical unit 154 can be used to count the number of sensing signals accumulated in each corresponding time bin in multiple receiving cycles to generate a corresponding statistical histogram. The abscissa of the statistical histogram represents the timestamp of each corresponding time bin, and the ordinate of the statistical histogram represents the accumulated sensing signal count value in each corresponding time bin. Optionally, the statistical unit 154 can be a histogram circuit.

[0076] During the sensing process, a large number of ambient light photons will also be received by the receiving module 14 to generate corresponding sensing signal counts. The probability of these ambient light photons being sensed and leaving counts in each time bin tends to be the same, forming the noise background (Noise Level) of the sensing data. In scenes with high ambient light intensity, the average level of the noise background measured is correspondingly high, and in scenes with low ambient light, the average level of the noise background measured is correspondingly low. On this basis, the photons of the sensing light signal emitted from the transmitting module 12 and reflected by the object 2 are sensed by the receiving module 14, and the corresponding sensing signal counts generated will be superimposed on the noise background, so that the sensing signal counts of the time bin corresponding to the sensed sensing light signal will be significantly higher than the sensing signal counts of other time bins, forming a corresponding signal peak. It can be understood that the counting height of the signal peak will be affected by factors such as the light emission power of the light source, the reflectivity of the object 2, and the detection range of the optical detection device 10, and the width of the signal peak will be affected by factors such as the width of the emitted light signal, the time jitter of the SPAD and TDC, etc. Thus, the timestamp t0 of the time bin corresponding to the signal peak is the flight time of the sensed sensing light signal, which can be used to calculate relevant sensing information such as depth information, distance information or proximity information of the object 2. It can be understood that the processing module 15 can also include a sensing information calculation unit 156. The sensing information calculation unit 156 can be used to calculate the relevant sensing information of the object 2 in space according to the timestamp t0 of the signal peak determined by the statistical histogram.

[0077] It is understandable that, according to the above sensing principle, the timestamp t0 of the sensed light signal reflected from the object 2 is calculated from the start time of the receiving cycle, that is, from the start time of the light signal emission cycle. Therefore, it is impossible to distinguish the specific moment in the light-emitting segment of the emission cycle from which the sensed sensing light signal is emitted, which will cause a certain degree of detection error. The above error can be reduced by shortening the duration of the light-emitting segment in the emission cycle. Optionally, in some embodiments, the duration of the light-emitting segment in the emission cycle of the light signal can range from 500 picoseconds (picosecond, ps) to 500 nanoseconds (nanosecond, ns), for example, it can be: 500ps, 600ps, 800ps, 1ns, 20ns, 50ns, 100ns, 200ns, etc.

[0078] Optionally, in some embodiments, the light signal emitted by the light emitting unit 120 with the light emission power P is within the preset time window t w The average value N of the sensing signal count of the sensing light signal generated within s It can be calculated using the following relationship (1):

[0079]

[0080] Among them, A is a fixed coefficient, P is the optical transmission power value of the optical signal, γ is the reflectivity of object 2, h represents Planck's constant, c represents the speed of light, λ represents the wavelength of light, M represents the number of SPADs, D is the lens entrance pupil radius, d represents the distance of object 2, θ1 is the lens transmittance, θ f is the filter transmittance, ε represents the probability of SPAD photons triggering avalanche, FF represents the fill factor, and N is the number of light signal emissions in a detection frame. In order to make the count statistically significant, the number of light signals emitted in a detection frame ranges from tens of thousands to millions.

[0081] The value of the reflectivity γ of the object 2 can be preset. Optionally, the value range of the object reflectivity γ is, for example, 8% to 95%. In some embodiments, the object reflectivity γ can be, for example, 10%.

[0082] The value of the distance d of the object 2 can be preset. Optionally, the object distance d can be the maximum value of the effective distance measurement range calibrated by the optical detection device 10 before leaving the factory. Alternatively, the object distance d can be the initial measurement value of the actual distance of the object currently detected by the optical detection device 10, and the optical detection device 10 can adjust the light emission power value P according to the initial measurement value of the actual distance of the object.

[0083] The photons of ambient light and the photons of the sensing light signal reflected from the object 2 have a certain probability of being received by the photosensitive pixel 142 of the receiving module 14. The type of the photosensitive pixel 142 can be SPAD, and then the sensing signal count is left in the corresponding time bin. The photons of ambient light and the photons of the sensing light signal are discrete random probability events that satisfy the Poisson distribution. Assume that in each time bin, the mathematical expectation value of the count of the photons of ambient light sensed is N n The mathematical expectation value of the number of photons sensed by the sensing light signal is N s , then N n is the average value of the sensing signal count under the noise background, N s The average value of the sensing signal counts superimposed on the noise background when the photons of the sensing light signal are sensed. Figure 6 As shown, the actual value N of the sensing signal count of the noise background actually calculated in a single time bin is n `And the actual value N of the sensing signal count of the sensing light signal s `Satisfying the Poisson distribution, the average value N of the sensing signal counts around the noise background n and the sensing signal count average value N of the sensing light signal s There is a certain range of numerical fluctuations. Assume that the standard deviations of the fluctuations are σ n and σ s In order to accurately find the signal peak, the actual value N of the sensing signal count in the time bin where the signal peak is located n `+N s `Need to be higher than the actual value N of the sensing signal count in the time bin where the noise background is located n ` can be effectively identified, so it is necessary to make the fluctuation of the actual value of the signal peak count low value (N n +N s )-(σ s+n ) can be more likely to be higher than the noise background of the actual value of the count fluctuation high value (N n +σ n ). According to the above conditions, the optical transmission power P of the optical signal transmitted by the transmitting module 12 can be adjusted according to the relationship (1) so that the N in the statistical histogram formed is s Satisfies the relationship (1):

[0084]

[0085] Among them, α is the confidence factor, which represents the credibility of the signal peak being higher than the noise background, σ s+n is the preset time window t w The standard deviation of the counts of the sensing signal generated by the photons of the internal ambient light and the photons of the sensing light signal, σ n is the preset time window tw The standard deviation of the number of photons of ambient light generated by the sensing signal. N n is the preset time window t w The average value of the sensing signal counts generated by the photons of ambient light sensed within, N n As the ambient light information can be obtained through the statistical histogram, N s is the preset time window t w Optionally, the preset time window t w It can be a time interval represented by a time bin or multiple unspecified time bins, and the corresponding sensing signal count average value N of the noise background n By setting the preset time window t w The actual value N of the sensing signal count of the noise background of each of the multiple time bins in n `Get the average.

[0086] The higher the optical emission power of the optical signal, the higher the average value N of the sensing signal count of the sensed sensing optical signal. s When the intensity of ambient light is higher, the average value N of the sensing signal count of the sensed noise background is n From the relation (2), it can be seen that the light transmission power of the adapted optical signal is directly related to the intensity of the ambient light. When the ambient light intensity is greater, the average value N of the sensing signal count of the noise background is n The larger the light emission power of the optical signal is, the smaller the confidence factor α that satisfies the relationship (2) will be, thereby affecting the accuracy of peak finding during the detection process. Therefore, when the ambient light intensity is greater, the optical detection device 10 also needs to increase the light emission power of the optical signal to maintain the signal-to-noise ratio of the statistical histogram. When the light emission power of the light-emitting unit 120 is fixed, the light emission power needs to be preset to be larger to meet the harsh scenes with large ambient light intensity. However, this will cause a waste of light emission power in scenes with weak ambient light, and it is also easy to reduce the life of the light source, increase the heat generation of the entire system, and increase the instability of the system.

[0087] Substitute the above relationship (1) into the relationship (2), and then use the statistical histogram obtained by the statistical unit 154 to determine the preset time window t w The average value of the sensing signal count within the noise background N n , the average value N of the sensing signal count of the determined noise background can be obtained. n The light emission power value range adapted to the ambient light information of the current scene is determined by using equations (1) and (2).

[0088] Optionally, in some embodiments, the control module 18 may include a power calculation unit 186, which is used to determine the light emission power value range adapted to the ambient light information in the current scene according to the above relationship (1), relationship (2) and the statistical histogram. It can be understood that in this case, the power calculation unit 186 can obtain the noise background count average value N representing the ambient light information from the statistical histogram. n .

[0089] Optionally, the control module 18 may include a power adjustment unit 184 for adjusting the light emission power of the light emitting unit 120. For example, but not limited to, the power adjustment unit 184 may adjust the light emission power of the light signal emitted by the light emitting unit 120 according to the light emission power range adapted to the ambient light information in the current scene determined by the power calculation unit 186, so that the light emission power of the light signal is as small as possible under the premise of adapting to the ambient light of the current scene.

[0090] Optionally, in some embodiments, the power adjustment unit 184 can adjust the light emission power of the entire light emitting unit 120 by correspondingly changing the light emission power of individual light sources. Alternatively, the power adjustment unit 184 can adjust the light emission power of the entire light emitting unit 120 by changing the number of light sources on the light emitting unit 120, for example, starting a smaller number of light sources to work and emit light when a lower light emission power is required, and starting a larger number of light sources to work and emit light when a higher light emission power is required.

[0091] Optionally, in some embodiments, the accuracy of the optical detection device 10 can be adjusted to be suitable for scenarios with different detection accuracy requirements. Optionally, the accuracy of the optical detection device 10 can be reflected by the size of the confidence factor α in the relationship (2). The larger the confidence factor α, the higher the credibility of the measurement result of the optical detection device 10, and the smaller the confidence factor α, the lower the credibility of the measurement result of the optical detection device 10. Therefore, under the premise that other conditions remain unchanged, if the confidence factor α is reduced, the optical emission power of the optical signal is also reduced accordingly, and if the confidence factor α is increased, the optical emission power of the optical signal is also increased accordingly.

[0092] Optionally, in some embodiments, the confidence factor α can be adjusted according to the application scenario, and the power calculation unit 186 can determine the light emission power value range that is compatible with the ambient light information and the confidence factor α of the current scene according to the adjusted relationship (1), relationship (2) and the statistical histogram, and the power adjustment unit 184 adjusts the light emission power of the light emitting unit 120 according to the recalculated light emission power value range. Optionally, in some other embodiments, an adjustment lookup table including the relationship between the confidence factor α, the ambient light information and the light emission power value can be preset by calibration. If the confidence factor α is adjusted, the power adjustment unit 184 can adjust the light emission power of the light emitting unit 120 according to the above adjustment lookup table.

[0093] Optionally, the control module 18 can obtain the ambient light information in the current scene through the statistical histogram, and then determine the corresponding adapted light emission power value according to the ambient light information, and then adjust the light emission power of the light-emitting unit 120 according to the determined light emission power value, so that the light emission power of the optical signal can be appropriately reduced in the scene with weak ambient light, thereby reducing the power consumption of the optical detection device 10, increasing the life of the light source, and improving the stability of the entire system.

[0094] The photons of the sensing light signal reflected from the object 2 satisfy the Gaussian distribution as a discrete random probability event accumulated over time, such as Figure 7 As shown in FIG. 1 , the count values ​​in the time bins on the left and right sides of the signal peak of the statistical histogram satisfying the Gaussian distribution will present a distribution shape that gradually increases toward the signal peak. Since the SPAD can only sense a single photon in one receiving cycle, when the optical detection device 10 is too close to the object 2 or the light emission power is relatively too strong, the return photons with a longer flight time will be submerged by the return photons with a shorter flight time, resulting in an avalanche pile-up effect, such as Figure 8 As shown in the figure, a signal peak with a total value significantly higher than the normal level will appear in the statistical histogram, but the count value in the time bin after the signal peak is significantly reduced, thus not satisfying the Gaussian distribution. The avalanche accumulation effect will cause the actual measured statistical histogram to be distorted, and the flight time measurement result will also be smaller. Fig. 9As shown, in some embodiments, the optical detection device 10 may be preset with a total value threshold range, and the control module 18 may further include a comparison unit 188. The comparison unit 188 may compare the actual total value of the sensing signal of all time bins in the statistical histogram with the preset total value threshold range. If the actual total value is greater than the maximum value of the preset total value threshold range, the light transmission power of the transmitting module 12 is reduced by the power adjustment unit 184. If the actual total value is lower than the minimum value of the preset total value threshold range, the light transmission power of the transmitting module 12 is increased by the power adjustment unit 184. If the actual total value of the sensing signal is within the preset total value threshold range, it means that the current light transmission power is appropriate and does not need to be adjusted. It can be understood that in this case, the power adjustment unit 184 of the control module 18 can adjust the light transmission power of the light emitting unit 120 according to the judgment result of the comparison unit 188.

[0095] Optionally, in some embodiments, the preset total value threshold range is, for example: (0.008N, 0.5N), where N is the number of receiving cycles for statistics, that is, the number of light signals emitted by the corresponding light-emitting unit 120. It is understandable that, in order to have statistical significance, in an effective detection process, the number of receiving cycles can be, for example, tens of thousands to millions. An effective detection process can also be defined as a detection frame, and the number of light signals continuously emitted by the light-emitting unit 120 in a detection frame corresponds to tens of thousands to millions. It is understandable that the preset total value threshold range can also be other values, such as: (0.01N, 0.1N), (0.007N, 0.4N), (0.02N, 0.6N), etc.

[0096] Optionally, in some embodiments, the control module 18 may also control the light emitting unit 120 to emit at least two groups of light signals at different light emission powers, for example: continuously emitting multiple light signals at a first light emission power as a first group of light signals, and continuously emitting multiple light signals at a second light emission power as a second group of light signals. The first light emission power is greater than the second light emission power. It is understandable that the first group of light signals and the second group of light signals may be emitted within one detection frame, or may be emitted within different detection frames, respectively. The comparison unit 188 of the control module 18 compares the first actual total value measured corresponding to the first group of light signals and the second actual total value measured corresponding to the second group of light signals with a preset total value threshold range, and selects a light emission power suitable for the current ambient light information according to the above comparison results.

[0097] Optionally, in some embodiments, if one of the first actual total value and the second actual total value is within a preset total value threshold range, the power adjustment unit 184 may select the first optical transmission power or the second optical transmission power corresponding to the first actual total value or the second actual total value within the preset total value threshold range as the adapted optical transmission power.

[0098] Optionally, in some embodiments, if the first actual total value and the second actual total value are both within a preset total value threshold range, the power adjustment unit 184 may select the optical transmission power corresponding to the first actual total value and the second actual total value that is closest to the middle value of the total value threshold range as the adapted optical transmission power.

[0099] Optionally, in some embodiments, if the first actual total value and the second actual total value are both within a preset total value threshold range, the power adjustment unit 184 may also select a smaller second optical transmission power as the adapted optical transmission power.

[0100] It can be understood that if the first actual total value and the second actual total value are both outside the preset total value threshold range, the control module 18 can control the light emitting unit 120 to continuously emit multiple optical signals as the third group of optical signals at the third optical transmission power, and to continuously emit multiple optical signals as the fourth group of optical signals at the fourth optical transmission power. The third optical transmission power can be less than the first optical transmission power and greater than the fourth optical transmission power, and the fourth optical transmission power can be greater than the second optical transmission power. The comparison unit 188 of the control module 18 compares the third actual total value measured corresponding to the third group of optical signals and the fourth actual total value measured corresponding to the fourth group of optical signals with the preset total value threshold range, and selects the optical transmission power suitable for the current ambient light information according to the above comparison results. The third actual total value and the fourth actual total value can be selected with reference to the selection method of the first actual total value and the second actual total value, and so on, until at least one actual total value that meets the preset total value threshold range is found, and the corresponding optical transmission power is used as the basis for adjusting the optical transmission power of the light emitting unit 120.

[0101] It can be understood that the selection of the third optical emission power and the fourth optical emission power can be determined based on the difference between the corresponding measured first actual total value and the second actual total value and the value of the total value threshold range. If it is larger than the larger value of the total value threshold range, the corresponding optical emission rate power is reduced; if it is smaller than the smaller value of the total value threshold range, the corresponding optical emission power is increased. In principle, this is to ensure that the measured actual total value is within the preset total value threshold range.

[0102] Optionally, in some embodiments, all or part of the functional units in the control module 18 and / or the processing module 15 may be firmware solidified in the memory 30 or computer software code stored in the memory 30. The control module 18 and the processing module 15 are executed by one or more corresponding processors (not shown) to control related components to implement corresponding functions. The processors include, but are not limited to, application processors (AP), central processing units (CPU), microcontrollers (MCU), etc. The memory 30 includes, but is not limited to, flash memory, electrically erasable programmable read only memory (EEPROM), programmable read only memory (PROM), hard disk, etc.

[0103] Optionally, in some embodiments, the processor and / or memory 30 may be disposed in the optical detection device 10, for example, integrated on the same circuit board as the transmitting module 12 or the receiving module 14. Optionally, in some other embodiments, the processor and / or memory 30 may also be disposed at other locations of the electronic device 1, for example, on the main circuit board of a mobile phone.

[0104] Optionally, in some embodiments, some or all of the functional units of the control module 18 and / or the processing module 15 may also be implemented by hardware, for example, by any one of the following technologies or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc. It is understandable that the above-mentioned hardware for implementing the functions of the control module 18 and / or the processing module 15 may be arranged in the optical detection device 10, for example, integrated on the same circuit board as the photoelectric sensor 140 or the light source. The above-mentioned hardware for implementing the functions of the control module 18 and / or the processing module 15 may also be arranged at other locations of the electronic device 1, for example, on the main board of the mobile phone.

[0105] Compared with the prior art, the optical detection device 10 of the present application can adjust the optical emission power of the optical signal adapted to the current scene, so as to reduce power consumption as much as possible while ensuring the detection effect, extend the service life of the light source, reduce the heat generation of the optical detection device 10, and improve the stability of the optical detection device 10.

[0106] It should be noted that those skilled in the art can understand that, without paying any creative labor, part or all of the embodiments of the present application, as well as part or all of the deformation, replacement, change, splitting, combination, expansion, etc. of the embodiments should be considered to be covered by the utility model creative idea of ​​the present application and belong to the protection scope of the present application.

[0107] Any reference in this specification to "one embodiment," "an embodiment," "an example embodiment," etc., indicates that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present application. Such phrases appearing in different places in this specification do not necessarily all refer to the same embodiment. In addition, when a particular feature or structure is described in conjunction with any embodiment, it is claimed that it is within the skill of those skilled in the art to implement such feature or structure in conjunction with other embodiments of these embodiments.

[0108] The orientation or positional relationship indicated by "length", "width", "up", "down", "left", "right", "front", "rear", "back", "front", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. that may appear in the specification of this application is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Similar numbers and letters represent similar items in the drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present application, the meaning of "multiple" or "multiple" is at least two or two, unless otherwise clearly and specifically defined. In the description of this application, it is also necessary to explain that, unless otherwise clearly specified and limited, "setting", "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0109] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. The terms used in the claims should not be understood to limit the invention to the specific embodiments disclosed in this specification. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. An optical detection device, characterized in that: include: A transmitting module, used for transmitting an optical signal; A receiving module, used for receiving optical signals and outputting corresponding sensing signals; A processing module, used for counting and counting the sensing signals generated by the receiving module in different time bins of the receiving cycle to form a statistical histogram; and A control module is used to adjust the optical transmission power of the optical signal emitted by the emission module according to the ambient light information obtained from the statistical histogram, the optical detection device is preset with a total value threshold range, the control module includes a comparison unit, the comparison unit compares the actual total value of the sensing signal of all time bins in the statistical histogram with the preset total value threshold range, the control module controls the emission module to continuously emit multiple optical signals with a first optical transmission power as a first group of optical signals, and continuously emit multiple optical signals with a second optical transmission power as a second group of optical signals, the first optical transmission power is greater than the second optical transmission power, the comparison unit compares the first actual total value measured corresponding to the first group of optical signals and the second actual total value measured corresponding to the second group of optical signals with the preset total value threshold range, and the power adjustment unit selects the optical transmission power of the ambient light information before adaptation according to the above comparison result.

2. The optical detection device according to claim 1, characterized in that: The sensing signal count generated by the photons of ambient light being received by the receiving module forms the noise background in the statistical histogram. A portion of the light signal emitted by the transmitting module is reflected back by an object in the space to form a sensing light signal. The sensing signal count generated by the photons of the sensing light signal being received by the receiving module is superimposed on the noise background to form a signal peak in which the sensing signal count is higher than the sensing signal count of the adjacent time bin. The light signal emitted by the transmitting module at the light transmitting power P is within the preset time window t. w The average value N of the sensing signal count of the sensing light signal generated within s Satisfies the relationship (1): Among them, A is a fixed coefficient, P is the light transmission power of the light signal, γ is the reflectivity of the object, h represents Planck's constant, c represents the speed of light, λ represents the wavelength of light, M represents the number of photosensitive pixels used for sensing by the receiving module, D is the lens entrance pupil radius, and d represents the distance of the object. is the lens transmittance, is the filter transmittance, ε represents the probability of photon-triggered avalanche of the photosensitive pixel, FF represents the fill factor, and N is the number of times the light signal is emitted in a detection frame.

3. The optical detection device according to claim 2, characterized in that: The object reflectivity γ has a value range of 8% to 95%.

4. The optical detection device according to claim 2, characterized in that: According to the relationship (1), the optical transmission power P of the optical signal transmitted by the transmitting module is adjusted so that the N s Satisfies the relationship (2): in, is the confidence factor, which represents the credibility of the signal peak being higher than the noise background. is the preset time window t w The standard deviation of the sensing signal counts generated by the photons of the internal ambient light and the photons of the sensing light signal, is the preset time window t w The standard deviation of the sensing signal counts generated by the photons of the internal ambient light, N n is the preset time window t w The average value of the sensing signal counts generated by the photons of ambient light sensed within, N n As ambient light information is obtained through the statistical histogram, the control module includes a power calculation unit, which is used to determine the range of light emission power values ​​adapted to the ambient light information of the current scene according to the above-mentioned relationship (1), relationship (2) and the statistical histogram, and the power adjustment unit adjusts the light emission power of the emission module according to the adapted light emission power value range determined by the power calculation unit.

5. The optical detection device according to claim 4, characterized in that: The confidence factor The power calculation unit determines the ambient light information and confidence factor of the current scene according to the adjusted relational expression (1), relational expression (2) and the statistical histogram. Adaptive optical transmit power value range.

6. The optical detection device according to claim 1, characterized in that: The power adjustment unit selects the first optical transmission power or the second optical transmission power corresponding to the first actual total value or the second actual total value within a preset total value threshold range as the adapted optical transmission power.

7. The optical detection device according to claim 1, characterized in that: If the first actual total value and the second actual total value are both within a preset total value threshold range, the power adjustment unit selects the optical transmission power corresponding to the first actual total value and the second actual total value that is closest to the middle value of the total value threshold range as the adapted optical transmission power.

8. The optical detection device according to claim 1, characterized in that: If the first actual total value and the second actual total value are both within the preset total value threshold range, the power adjustment unit selects the smaller second optical transmission power as the adapted optical transmission power.

9. The optical detection device according to any one of claims 1 to 8, characterized in that: A portion of the light signal emitted by the transmitting module is reflected back by an object in space to form a sensing light signal. The processing module is also used to obtain the flight time corresponding to the sensing light signal through a statistical histogram to calculate relevant sensing information of the object.

10. An electronic device, characterized in that: The electronic device comprises the optical detection device as claimed in any one of claims 1 to 9, and further comprises an application module, wherein the application module is used to implement corresponding functions according to the sensing information obtained by the optical detection device.

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