CN114019474A

CN114019474A - Emission module, optical detection device and electronic equipment

Info

Publication number: CN114019474A
Application number: CN202111104523.7A
Authority: CN
Inventors: 李佳鹏
Original assignee: Shenzhen Fushi Technology Co Ltd
Current assignee: Shenzhen Fushi Technology Co Ltd
Priority date: 2021-09-22
Filing date: 2021-09-22
Publication date: 2022-02-08

Abstract

The application discloses transmission module, including luminescence unit, photoinduction sensor and control module. The light emitting unit is used for emitting a light signal. The light sensing sensor is used for detecting ambient light information. The control module comprises a power adjusting unit, and the power adjusting unit is used for adjusting the light emitting power of the light signal emitted by the light emitting unit according to the ambient light information detected by the light sensing sensor. The application also discloses an optical detection device comprising the emission module and electronic equipment comprising the optical detection device.

Description

Emission module, optical detection device and electronic equipment

Technical Field

The present application relates to the field of photoelectric sensing technology, and more particularly, to an emission module, an optical detection apparatus, and an electronic device.

Background

The Time of Flight (TOF) measurement principle is to calculate the distance, or depth, of an object by measuring the Time of Flight of an optical signal in space, and is widely applied to the fields of consumer electronics, unmanned driving, AR/VR, and the like due to its advantages of long sensing distance, high precision, low energy consumption, and the like.

The optical detection device using the TOF principle comprises a transmitting module and a receiving module. The transmitting module is used for transmitting optical signals to the space, and the receiving module is used for receiving the optical signals returned from the object and calculating the distance of the object according to the time required by the optical signals from transmitting to receiving.

However, in order to distinguish the sensing light signal returned from the object from the background noise caused by the ambient light, it is often necessary for the transmitting module to transmit the light signal to the space with a higher transmitting power, so as to ensure that a sufficient amount of the sensing light signal returned from the object can be received even under the harsher ambient light conditions. Therefore, the transmitting module needs to maintain a higher level of light emission power during operation, which increases the overall power consumption of the TOF apparatus on the one hand, and also shortens the device lifetime of the transmitting module on the other hand.

Disclosure of Invention

In view of the above, the present application provides a transmitting module, an optical detection device and an electronic apparatus capable of solving the problems in the prior art.

The embodiment of the application provides an emission module, which comprises a light emitting unit, a light induction sensor and a control module. The light emitting unit is used for emitting a light signal. The light sensing sensor is used for detecting ambient light information. The control module comprises a power adjusting unit, and the power adjusting unit is used for adjusting the light emitting power of the light signal emitted by the light emitting unit according to the ambient light information detected by the light sensing sensor.

In an embodiment of the invention, the light emitting unit comprises a single light source or a plurality of light sources, the light sensing sensor and the light sources are packaged together in one package; or,

the light-sensing sensor and the light source are packaged separately to form different individuals.

In the embodiment of the present invention, an adjustment lookup table is preset, where the adjustment lookup table includes a corresponding relationship between ambient light information and an adapted light emission power value, the power adjustment unit determines, according to the ambient light information obtained by the light-sensing sensor and the corresponding relationship in the adjustment lookup table, a light emission power value adapted to a scene where the power adjustment unit is located, and then adjusts the light emission power of the light emitting unit according to the determined adapted light emission power value.

In the embodiment of the present invention, the light signal emitted by the light emitting unit may be one or more of visible light, infrared light and near-infrared light.

In an embodiment of the present invention, the light sensing sensor may be configured to sense a light intensity of a light signal in a scene as the ambient light information, and the power adjusting unit adjusts a light emitting power of the light signal emitted by the light emitting unit according to the sensed light intensity of the light signal.

In an embodiment of the present invention, one or more different light sensing channels are disposed on a path of the light sensing sensor receiving the ambient light: the light-induced sensor comprises a visible light full-spectrum channel, a red light channel, a green light channel, a blue light channel, an infrared light channel, a wide-spectrum channel and/or an infrared light channel, and the light-induced sensor comprises light filters and photoelectric conversion devices corresponding to different light-induced channels.

In the embodiment of the present invention, the light emitting unit includes a single light source or a plurality of light sources, and the power adjusting unit adjusts the light emission power of the entire light emitting unit by correspondingly changing the light emission power of the individual light sources; or

The power adjusting unit adjusts the light emitting power of the whole light emitting unit by changing the number of the light sources on the light emitting unit to emit light.

In the embodiment of the invention, the light source is selected from any one or more of a vertical cavity surface emitting laser, an edge emitting laser, a light emitting diode and a laser diode.

The embodiment of the application provides an optical detection device, which comprises a receiving module, a processing module and the transmitting module in the above embodiments. The receiving module is used for receiving the returned optical signal and outputting a corresponding sensing signal. The processing module is used for obtaining related sensing information according to the sensing signals generated by the receiving module.

The embodiment of the present application provides an electronic device, which includes the optical detection apparatus as described in the above embodiments. The electronic device may further include an application module, which may be configured to implement a corresponding function according to the sensing information obtained by the optical detection apparatus.

The optical detection device can adjust the light emission power of the emission module according to the ambient light condition in the scene, so that the emission power of the optical signal can be properly reduced in the scene with weak ambient light, the power consumption of the optical detection device can be reduced, the service life of the light source is prolonged, and the stability of the whole system is improved.

Additional aspects and advantages of embodiments of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of embodiments of the present application.

Drawings

Fig. 1 is a schematic diagram of a functional module of an optical detection apparatus applied to an electronic device according to an embodiment of the present application;

FIG. 2 is a functional block diagram of the optical detection device of FIG. 1;

FIG. 3 is a schematic diagram illustrating the relationship between different signals of an optical detection apparatus provided in an embodiment of the present application;

FIG. 4 is a schematic diagram of a functional module of an optical apparatus applied to an electronic device according to another embodiment of the present application;

FIG. 5 is a statistical histogram of an optical inspection apparatus provided in an embodiment of the present application;

FIG. 6 is a graph showing the relationship between the signal peak fluctuations and the noise background fluctuations of FIG. 5;

fig. 7 is a schematic functional block diagram of an optical detection apparatus according to another embodiment of the present application.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

In the detailed description of the embodiments herein, it will be understood that when a substrate, a sheet, a layer, or a pattern is referred to as being "on" or "under" another substrate, another sheet, another layer, or another pattern, it can be "directly" or "indirectly" on the other substrate, the other sheet, the other layer, or the other pattern, or one or more intervening layers may also be present. The thickness and size of each layer in the drawings of the specification may be exaggerated, omitted, or schematically represented for clarity. Further, the sizes of the elements in the drawings do not completely reflect actual sizes.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The following disclosure provides many different embodiments, or examples, for implementing different features of the application. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or reference letters in the various examples, which have been repeated for purposes of simplicity and clarity and do not in themselves dictate a relationship between the various embodiments and/or configurations discussed.

In the description of the present application, it is to be understood that the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the application. One skilled in the relevant art will recognize, however, that the subject matter may be practiced without one or more of the specific details, or with other structures, components, and so forth. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring the application.

The embodiment of the application provides an emission module, which comprises a light-emitting unit, a light-sensing sensor and a control module, wherein the light-emitting unit is used for emitting a light signal. The light sensing sensor is used for detecting ambient light information. The control module adjusts the light emission power of the light emitting unit to emit the light signal according to the ambient light information detected by the light sensing sensor.

Alternatively, in some embodiments, the light emitting unit emits a light signal to the space to sense sensing information related to depth information, distance information, proximity information, and the like of an object in the space. The optical signal may be, for example, an optical pulse having a preset frequency. Wherein at least a portion of the emitted optical signal is reflected back by an object in the space to form a sensed optical signal.

An embodiment of the present application provides an optical detection apparatus, which includes the above-mentioned transmitting module, receiving module and processing module. The receiving module is configured to receive an optical signal and output a corresponding sensing signal, and the processing module obtains related sensing information according to the sensing signal generated by the receiving module, for example, but not limited to, obtaining one or more of depth information, distance information, and proximity information of the object.

Optionally, the optical detection device may detect the related information based on a time-of-flight principle. The transmitting module and the receiving module are adjacently arranged side by side, and the distance between the transmitting module and the receiving module can be, for example, 2 millimeters (mm) to 20 mm. It is understood that, in some embodiments, both the transmitted signal and the received signal are optical signals, and the distance between the transmitting module and the receiving module refers to the distance between the optical axes of the respective optical systems. The transmitting module comprises a light emitting surface for emitting optical signals, the receiving module comprises a light incident surface for receiving the optical signals, and 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 to the same side of the optical detection device.

Optionally, the optical signal received by the receiving module may include the sensing optical signal and/or other optical signals that are not emitted by the emitting module or reflected back by an object.

Alternatively, the sensing signal may be an electrical signal. Alternatively, the sensing signal may be other signals, such as a magnetic signal, depending on the conversion principle of photons by the receiving module.

Embodiments of the present application also provide an electronic device including the optical detection apparatus. The electronic equipment realizes corresponding functions according to the sensing information obtained by the optical detection device. The sensing information is, for example: and one or more of proximity information, depth information, distance information and the like of the object in the space. The depth information may be used in the fields of 3D modeling, face recognition, automatic driving, machine vision, monitoring, unmanned aerial vehicle control, Augmented Reality (AR)/Virtual Reality (VR), instant positioning, Mapping (SLAM), and the like, for example, and the present application does not limit the present invention. The proximity information is used, for example, to determine whether or not an object is in proximity. The optical detection device is, for example, a laser radar, and can be used for obtaining depth information or distance information of an object in a scene to assist in realizing automatic driving control of an automobile.

Hereinafter, an embodiment in which the optical detection apparatus is applied to an electronic device will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of functional modules of an optical detection apparatus 10 applied to an electronic device 1 according to an embodiment of the present application. Fig. 2 is a schematic functional block diagram of the optical detection apparatus 10 according to an embodiment of the present disclosure.

Referring to fig. 1 and 2, the electronic device 1 comprises an optical detection apparatus 10 for measuring an object 2 in a space using the principle of time-of-flight measurement of light to obtain corresponding information of the object 2, such as, but not limited to: one or more of proximity information, depth information, and distance information. The electronic device 1 may further comprise an application module 20, and the application module 20 may implement related functions according to the obtained corresponding sensing information of the object 2, such as but not limited to: whether the object 2 appears in a preset range in front of the electronic equipment 1 can be judged according to the proximity information of the object 2; or, the electronic device 1 may be controlled to avoid the obstacle according to the distance information of the object 2; or, 3D modeling, face recognition, machine vision, etc. may be performed according to the depth information of the object 2.

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 may perform depth information sensing based on the direct time-of-flight detection principle. For example, the DTOF measurement device 10 may transmit an optical signal into the space and receive a sensed optical signal reflected by the object 2 in the space, where the time difference between the transmission of the optical signal and the reception of the sensed optical signal is referred to as the time of flight t, and the distance traveled by the optical signal during the time of flight is calculatedTo obtain depth information of the object 2

Where c is the speed of light.

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 is based on the indirect time-of-flight detection principle to perform depth information sensing. The ITOF measuring device 10 obtains depth information of the object 2 by calculating a phase difference between the transmitted light signal and the received sensing light signal.

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

Optionally, as shown in fig. 2, the optical detection apparatus 10 includes a transmitting module 12, a receiving module 14, a light-sensing sensor 16, and a control module 18. The transmitting module 12 is configured to transmit an optical signal to a space, where at least a portion of the transmitted optical signal can be reflected by the object 2 in the space to form a sensing optical signal, and at least a portion of the sensing optical signal is received by the receiving module 14. The sensing optical signal carries corresponding information of the object 2, such as: depth information, distance information, proximity information, and the like.

The emission module 12 includes a light emitting unit 120 and a modulation element 124. The light emitting unit 120 is used for emitting a light signal. The modulation element 124 is used for modulating the light signal emitted by the light emitting unit 120 to form a light signal which can be used for sensing and projecting the light signal to the space. Optionally, the light signal emitted by the emitting module 12 is, for example and without limitation, a speckle pattern or a flood light beam.

Optionally, in some embodiments, the modulating element 124 is, for example, a diffusion sheet (Diffuser) or a light-homogenizing sheet, and is used for homogenizing the light signal emitted by the light-emitting unit 120 to form a flood light beam.

Optionally, in some embodiments, the modulation Element 124 is, for example, a Diffractive Optical Element (DOE), and is configured to replicate the Optical signal emitted by the light emitting unit 120 and spread the Optical signal within a preset field angle range to form a speckle pattern. The speckle patterns can be arranged regularly, or can be arranged irregularly or randomly.

The DOE is used to duplicate the optical signal emitted by the light emitting unit 120, and the optical signal emitted to the object 2 is composed of a plurality of duplicated optical signals, which is beneficial to expanding the field angle range of the optical detection apparatus 10 and improving the sensing effect.

Alternatively, in some embodiments, the modulation element 124 may be another suitable type of beam modulation element, such as but not limited to a microlens array, and the like, which is not particularly limited in this application.

Optionally, in some embodiments, the emission module 12 may further include other suitable optical elements, such as: a lens (not shown) is disposed on a path of the light signal emitted from the light emitting unit 120, and the lens may be disposed between the light emitting unit 120 and the modulation element 124, and is used for collimating or converging the light signal emitted from the light emitting unit 120 and then transmitting the light signal to the modulation element 124. The lens may be a combination of a plurality of individual lenses.

It should be understood that the embodiments of the present application do not specifically limit the wavelength range of the optical signal emitted by the light emitting unit 120. Alternatively, the light signal emitted by the light emitting unit 120 may be, for example, visible light, infrared light, near-infrared light, ultraviolet light, or the like.

Alternatively, in some embodiments, the light emitting unit 120 may include a single light source or a plurality of light sources. The plurality of light sources may be, for example, a regularly arranged or irregularly arranged light source array. As shown in fig. 2, the light Emitting unit 120 is a Vertical Cavity Surface Emitting Laser (VCSEL), and the light Emitting unit 120 may include a semiconductor substrate and a VCSEL array die formed by a plurality of VCSEL light sources arranged on the semiconductor substrate.

Optionally, in some embodiments, the Light source of the Light Emitting unit 120 may also be a Light source in the form of an Edge Emitting Laser (EEL), a Light Emitting Diode (LED), a Laser Diode (LD), or the like. The edge-emitting laser may be a Fabry Perot (FP) laser, a Distributed Feedback (DFB) laser, an Electro-absorption Modulated (EML) laser, and the like, which is not limited in the embodiment of the present application.

Optionally, in some embodiments, the receiving module 14 may include a photosensor 140. The photosensor 140 includes, for example, a single photosensitive pixel 142 or a pixel array composed of a plurality of photosensitive pixels 142, for receiving a sensing light signal reflected by the object 2 to obtain related sensing information, such as, but not limited to, depth information of the object 2.

Alternatively, in some embodiments, the photosensitive pixels 142 may include Single Photon Avalanche Diodes (SPADs), Avalanche Photodiodes (APDs), photodiodes, and/or other suitable photoelectric conversion elements. For example, but not limiting of, each photosensitive pixel 142 may include a single SPAD and/or a combination of SPADs.

Optionally, in some embodiments, the receiving module 14 may further include a readout circuit (not shown) formed by one or more of a signal amplifier, a Time-to-Digital Converter (TDC), an Analog-to-Digital Converter (ADC), and the like, which are connected to the photosensor 140. Alternatively, the readout circuit may be partially or completely integrated in the photosensor 140.

Optionally, the receiving module 14 may further include a lens unit 144, which is configured to receive the sensing optical signal returned from the object 2, collimate or converge the sensing optical signal, and transmit the collimated or converged sensing optical signal to the photosensitive pixel 142 on the photosensor 140. The lens unit 144 may be a combination of a plurality of single lenses.

Alternatively, the optical detection device 10 may detect the relevant information based on the time-of-flight principle. The transmitting module 12 and the receiving module 14 are adjacently arranged side by side, and the distance between the transmitting module 12 and the receiving module 14 can be, for example, 2 millimeters (mm) to 20 mm. It is understood that, in some embodiments, both the transmitting module 12 and the receiving module 14 transmit and receive optical signals, and the distance between the transmitting module 12 and the receiving module 14 refers to the distance between the optical axes of the respective optical systems. The emitting module 12 includes a light emitting surface for emitting an optical signal, the receiving module 14 includes a light incident surface for receiving the optical signal, and when the emitting module 12 and the receiving module 14 are arranged side by side, the light emitting surface of the emitting module 12 and the light incident surface of the receiving module 14 face the same side of the optical detection apparatus 10.

Optionally, the control module 18 may be configured to control the emission condition of the light emitting unit 120 in the emission module 12, for example: may be used to control the frequency of the emitted light signal, the position of the light source that is lit at different times, the luminous 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 configured to control the light emitting unit 120 to emit a light signal into the space at a preset frequency, where the light signal is a light pulse with the preset frequency.

As shown in fig. 3, in some embodiments, the emission control unit 180 may control the light emitting unit 120 to emit the light signal according to an emission control signal having a preset frequency. It is understood that the emission control signal may be a driving signal applied to the driving circuit of the light emitting unit 120. Optionally, the emission control signal may be a series of control pulse signals, for example: a square wave pulse signal. The control pulse signal includes alternately high level segments and low level segments, and the light emitting unit 120 is controlled to emit light into the space continuously in the high level segments and stop emitting light in the low level segments, thereby emitting corresponding light pulses as the light signal. Therefore, during the time sequence corresponding to the high level segment, the light emitting unit 120 continuously emits the light signal to the space, and at least a part of the light signal can be reflected from the object 2 in the space to form the sensing light signal.

It is understood that the frequency of the optical signal may be set according to the detection range of the optical detection device 10. For example: one emission period of the light signal includes a light emitting section in which the light emitting unit 120 continuously emits the light signal and an extinguishing section in which light emission is stopped. The emission period of the optical signal needs to be longer than the maximum flight time corresponding to the detection range, so that the optical signal emitted in one emission period can effectively detect the object 2 in the detection range.

Alternatively, in some embodiments, some or all of the functional units of the control module 18 may be integrated into the transmitting module 12.

Optionally, in some embodiments, the control module 18 may further include a receiving control unit 182. The receiving control unit 182 is configured to control the receiving module 14 to synchronously turn on the receiving sensor at the starting time of each emitting period of the optical signal to sense the returned photons. Thus, the receiving module 14 has a receiving period corresponding to the transmitting period of the optical signal, the starting time of the receiving period corresponds to the starting time of the transmitting period, and the ending time of the receiving period corresponds to the ending time of the transmitting period. Optionally, in some embodiments, the start time of the receiving period is synchronized with the start time of the transmitting period, and the end time of the receiving period is synchronized with the end time of the transmitting period.

Specifically, in some embodiments, the receiving control unit 182 is configured to control the light-sensitive pixels 142 to synchronously start sensing the returned photons at the start time of each emission period of the light signal. The photosensitive pixel 142 is, for example, a SPAD, which can sense only a single photon in one receiving period, and an avalanche effect is formed to generate a corresponding sensing signal once the SPAD is triggered by the single photon in one receiving period. The SPAD after avalanche needs to be quenched reset to restore the bias voltage above the breakdown voltage to re-sense the photon in the next receive cycle. Based on the above characteristics, the SPAD can generate a corresponding sensing signal in response to a returned one of the sensing photons during one of the receiving periods. It will be appreciated that the SPAD may not respond to a photon during one receive period without generating a corresponding sense signal, but whether or not it responds to a photon, the SPAD is reset before the end of one receive period to resume sensing received photons at the beginning of the next receive period.

Alternatively, in some embodiments, some or all of the functional units of the control module 18 may be integrated in the receiving module 14.

Optionally, in some embodiments, the optical detection device 10 may further include a processing module 15. The processing module 15 is for example used to determine depth information of an object from the time difference between the emission instant of the light signal and the sensed instant of the returned sensed light signal. However, not limited to this, in other embodiments, the processing module 15 may also obtain the relevant sensing information according to the received sensing light signal and based on other suitable detection principles.

Alternatively, as shown in fig. 1, the processing module 15 may be integrated in the optical detection device 10. Alternatively, as shown in fig. 4, in some embodiments, the processing module 15 may also be disposed in other positions in the electronic device 1 besides the optical detection apparatus 10, for example, the processing module 15 may be a main control module of the electronic device 1, which is not limited in this application. Alternatively, as shown in fig. 1, the light-sensitive sensor 16 may be integrated within the optical detection device 10. Alternatively, as shown in fig. 4, the light-sensing sensor 16 may be provided at a position other than the optical detection device 10 in the electronic apparatus 1.

Referring to fig. 2, 3 and 5, in some embodiments, the processing module 15 may include a timing unit 150, a counting unit 152 and a counting unit 154. The timing unit 150 may divide the receiving period into a plurality of time bins from the starting time, where each time bin corresponds to a preset time interval Δ t. Optionally, the time intervals Δ t corresponding to each time bin are respectively equal. Alternatively, the time interval Δ t may be a minimum time interval Δ t that the TDC can resolve. It will be appreciated that the time difference between each time bin and the start of the receive cycle may be taken as a timestamp for that time bin. The timing unit 150 may be further configured to calculate a time difference between a time instant of a sensing signal generated by the receiving module 14 in response to the valid sensing photon emitted from the object 2 in a receiving period and a starting time instant of the receiving period, as a time stamp of the sensing signal.

Optionally, in some embodiments, the counting unit 152 may be configured to perform cumulative counting in the time bins with corresponding time stamps according to the time stamps of the sensing signals, that is, to add one more to the counted number of sensing signals with the same time stamp in the time bins. It will be appreciated that for embodiments in which SPAD is used as a photosensitive pixel 142, a photosensitive pixel 142 can only generate a sense signal in response to a single photon during each receive period, thus accumulating one in one of the time bins, or cannot receive any photon without generating a sense signal, thus not accumulating in any one of the time bins.

Optionally, in some embodiments, the statistical unit 154 may be configured to perform statistics on the number of sensing signals accumulated in each corresponding time bin in a plurality of receiving periods 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. Alternatively, the statistical unit 154 may be a histogram circuit.

During the sensing process, a large number of photons of the ambient light are also received by the receiving module 14 to generate a corresponding sensing signal count. The probability that photons of these ambient light are sensed and left to count in each time bin tends to be the same, constituting the Noise floor (Noise Level) of the sensed data, which is correspondingly higher in the scene of higher ambient light intensity and lower in the scene of lower ambient light intensity. On this basis, the sensing signal counts corresponding to the valid sensing photons reflected from the object 2 are superimposed on the noise background such that the sensing signals in the time bins having the same time stamp as the valid sensing photons areThe number count will be significantly higher than the sensed signal counts of other time bins, thereby forming corresponding signal peaks. It will be appreciated that the count height of the signal peaks may be influenced by the emitted light power of the light source, the reflectivity of the object 2, the detection range of the optical detection device 10, etc., and the width of the signal peaks may be influenced by the width of the emitted optical signal, the time jitter of the SPAD and TDC, etc. Whereby the time stamp t of the time bin corresponding to the highest count of the signal peaks₀I.e. the time of flight of the effective sensing photons reflected by the object, from which depth information or distance information of the object 2 can be calculated. It is to be understood that the processing module 15 may further include a sensed information calculation unit 156. The sensing information calculation unit 156 may be adapted to calculate the time stamp t of a signal peak from a statistical histogram₀To calculate the relevant sensing information of the object 2 in space.

It will be appreciated that the time stamp t of a valid sensed photon reflected from the object 2 is calculated according to the sensing principle described above₀Is clocked from the start of the receive period, and correspondingly, from the start of the optical signal transmit period. Therefore, the detected effective sensing photons cannot be distinguished from the specific moment in the light-emitting section of the emission period, so that a certain detection error can be caused, and the error can be reduced by shortening the duration of the light-emitting section in the emission period. Optionally, in some embodiments, a duration of the light emitting segment in the emission period of the optical signal may range from 500 picoseconds (ps) to 500 nanoseconds (ns), for example, may be: 500ps, 600ps, 800ps, 1ns, 20ns, 50ns, 100ns, or 200ns, and the like.

Both the photons of the ambient light and the photons of the sensing light signal reflected from the object 2 have a certain probability to be received by the photosensitive pixel 142 of the receiving module 14, the type of the photosensitive pixel 142 may be SPAD, and the sensing signal count is left in the corresponding time bin. The photons of the ambient light and the photons of the sensing light signal both satisfy a Poisson distribution as discrete random probability events, assuming that within each time bin, the photons of the ambient lightThe mathematical expected value of the count being sensed is Nn, the mathematical expected value of the count being sensed of the photons of the sensed light signal is Ns, then Nn is the average value of the counts of the noise background, and Ns is the average value of the counts of the valid sensed photons of the sensed light signal that are sensed and superimposed on the noise background. As shown in fig. 6, the noise background count actual value Nn 'and the effective sensing photon count actual value Ns' actually measured in a single time bin satisfy the poisson distribution, and there may exist a certain range of numerical fluctuations around the noise background count average value Nn and the effective sensing photon count average value Ns, respectively, assuming that standard deviations of the fluctuations are σ n and σ s, respectively. In order to accurately find out the signal peak, the actual count value Nn ' + Ns ' of the time bin where the signal peak is located needs to be higher than the actual count value Nn ' of the time bin where the noise background is located to be effectively identified, so that the fluctuation low value (Nn + Ns) - (sigma) of the signal peak needs to be enabled_s+n) Can be higher than the fluctuation height value (Nn + sigma) of the noise background with greater probability_n) From the above conditions, equation (1) can be obtained, expressed as follows:

where α is a confidence factor representing the confidence that the signal peak is above the background of the noise, σ_s+nIs the standard deviation, σ, of the counts of the sensed signals generated by photons of the ambient light and photons of the sensed light signal_nIs the standard deviation of the counts of the sensing signal produced by photons of ambient light.

The higher the emitted optical power of the optical signal, the correspondingly higher the sensed effective sensed photon count average Ns. The higher the intensity of the ambient light, the correspondingly larger the average value Nn of the sensed noise background counts. As can be known from the formula (1), the required emitted light power of the optical signal has a direct relationship with the intensity of the ambient light, and when the intensity of the ambient light is larger, the noise background count average value Nn is correspondingly larger, and if the emitted light power of the optical signal is kept unchanged, the confidence factor α satisfying the formula (1) is reduced, thereby affecting the accuracy of peak searching in the detection process. Thus, the optical detection device 10 also needs to increase the emitted optical power of the optical signal to maintain the signal-to-noise ratio of the statistical histogram when the ambient light intensity is larger. In the case that the emitted light power of the light emitting unit 120 is fixed, the emitted light power needs to be preset to be larger to meet a severe scene with larger ambient light intensity, however, the emitted light power is wasted in a scene with weak ambient light, the service life of the light source is easily reduced, and the heat generation of the whole system and the instability of the system are increased.

Optionally, the light sensing sensor 16 may be used for sensing ambient light information of a scene where the optical detection device 10 is located, where the ambient light information includes, but is not limited to, a wavelength, a light intensity, a color temperature, and the like of ambient light. One or more different light sensing channels are arranged on a path of the light sensing sensor for receiving the ambient light, and the light sensing sensor comprises optical filters and photoelectric conversion elements corresponding to the different light sensing channels so as to correspondingly sense the ambient light information in different wavelength range portions in the ambient light. Optionally, the photosensitive channel includes one or more of a visible full-spectrum channel (Clear), a Red channel (Red), a Green channel (Green), a Blue channel (Blue), and a Wide-spectrum channel (Wide). The filter of the visible light full-spectrum channel penetrates through light rays in a visible light wave band, the filter of the red light channel penetrates through light rays in a red light wave band, the filter of the green light channel penetrates through light rays in a green light wave band, the filter of the blue light channel penetrates through light rays in a blue light wave band, the filter of the infrared light channel penetrates through light rays in an infrared or near-red wave band, and the filter of the wide-spectrum channel penetrates through light rays in visible light and infrared light wave bands. The light-sensitive sensor 16 may provide spectral information for each of the Channels (CRGBWs) and determine corresponding ambient light information therefrom.

Optionally, the light sensing channel of the light sensing sensor 16 may further include an infrared light channel (IR). The light-sensing sensor 16 can directly obtain information related to infrared light or near infrared light in a scene as ambient light information through an infrared light channel. Alternatively, the light-sensing sensor 16 may determine information related to infrared light or near-infrared light as ambient light information by subtracting information of a full-spectrum channel from information of an obtained wide-spectrum channel, so that an infrared light channel does not need to be set.

Optionally, the control module 18 may further include a power adjusting unit 184, which is configured to adjust the light emitting power of the light emitting unit 120. For example, but not limiting of, the power adjustment unit 184 may adjust the power of the light sensor 16 according to ambient light information sensed by the light sensor, such as: the intensity of the ambient light, and the light emission power of the light emitting unit 120 are adjusted so that the emission power of the light signal is as small as possible under the premise of adapting to the ambient light of the current scene.

Alternatively, in some embodiments, the power adjusting unit 184 may adjust the light emission power of the whole light emitting unit 120 by correspondingly changing the light emission power of the individual light sources. Alternatively, the power adjusting unit 184 may adjust the light emitting power of the whole light emitting unit 120 by changing the number of light sources on the light emitting unit 120, for example: when the light emission power is needed to be lower, a smaller number of light sources are started to work and emit light, and when the light emission power is needed to be higher, a larger number of light sources are started to work and emit light.

Optionally, in some embodiments, the optical detection apparatus 10 is preset with an adjustment lookup table, where the adjustment lookup table includes a corresponding relationship between the ambient light information and the light emission power value, which can be obtained by calibrating the light emission power of the optical detection apparatus 10 adapted under different ambient light scenes. The adjustment lookup table may be set in advance according to calibration and stored in the memory 30 of the optical detection apparatus 10 or the electronic device 1 for reading. The power adjustment unit 184 may determine the light emission power value adapted to the scene according to the ambient light information obtained by the light sensing sensor 16 and the corresponding relationship in the adjustment lookup table.

Optionally, in some embodiments, the adjustment lookup table includes a correspondence between the ambient light intensity value and the adapted light emission power value, from which the light emission power value of the optical detection device 10 adapted thereto can be determined according to the sensed ambient light intensity value. It will be appreciated that in other embodiments, the adjustment look-up table may also include light emission power values and other ambient light information, such as: color temperature, wavelength, etc.

Optionally, the power adjusting unit 184 may obtain an ambient light intensity value of a scene where the light sensing sensor 16 is located, then read the adjustment lookup table according to the ambient light intensity value to determine a corresponding adaptive light emission power value, 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 properly reduced in a scene where the ambient light is weak, thereby reducing the power consumption of the optical detection apparatus 10, prolonging the lifetime of the light source, and improving the stability of the whole system.

In some embodiments, as shown in fig. 7, the light-sensitive sensor 16 may be integrated on the emission module 12. For example: the emission module 12 may include a light emitting unit 120, a light sensing sensor 16, and a control module 18. The light emitting unit 120 is used for emitting light signals to the space, and at least part of the emitted light signals are reflected from objects in the space to form sensing light signals. The light-sensitive sensor 16 is used to detect ambient light information within the space. The control module 18 adjusts the emitting power of the light emitting unit 120 to emit light signals to the space according to the ambient light information detected by the light sensing sensor 16. Alternatively, the light-sensing sensor 16 and the light source on the light-emitting unit 120 may be packaged together in a package. Alternatively, the light-sensing sensor 16 and the light source on the light-emitting unit 120 may be packaged separately to form a different entity.

Alternatively, in some embodiments, the light-sensitive sensor 16 may also be disposed on the electronic device 1 to which the optical detection apparatus 10 is mounted. For example: the electronic device 1 is a mobile phone, and the light-sensing sensor 16 can be arranged in the middle of the top of the front surface of the mobile phone; alternatively, the light-sensing sensor 16 is disposed on a camera module (not shown) on the back of the mobile phone.

Optionally, in some embodiments, the optical 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 and the like. The light-sensitive sensor 16 may be used to detect the light intensity of infrared light or near-infrared light in the scene where the optical detection device 10 is located as ambient light information. The power adjusting unit 184 of the control module 18 adjusts the light signal emission power of the light emitting unit 120 according to the sensed light intensity of the infrared light or the near-infrared light in the scene.

Alternatively, in some embodiments, all or some of the functional units in the control module 18 and/or the processing module 15 may be firmware that is fixed in the memory 30 or computer software code that is stored in the memory 30. The control module 18 and the processing module 15 are executed by corresponding one or more processors (not shown) to control the relevant components to implement the corresponding functions. Such as, but not limited to, an Application Processor (AP), a Central Processing Unit (CPU), a Microcontroller (MCU), etc. The Memory 30 includes, but is not limited to, a Flash Memory (Flash Memory), a charge Erasable Programmable read only Memory (EEPROM), a Programmable Read Only Memory (PROM), a hard disk, and the like.

Optionally, in some embodiments, the processor and/or the memory 30 may be disposed within the optical detection device 10, such as: integrated on the same circuit board as the transmission module 12 or the reception module 14. Optionally, in some other embodiments, the processor and/or the memory 30 may also be disposed in other positions of the electronic device 1, such as: the main circuit board of the mobile phone.

Optionally, in some embodiments, part 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 or a combination of the following technologies: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like. It will be appreciated that the above-mentioned hardware for implementing the functions of the control module 18 and/or the processing module 15 may be provided within the optical detection device 10, such as: integrated on the same circuit board as 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 disposed at other positions of the electronic device 1, such as: is arranged on the mainboard of the mobile phone.

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

It should be noted that, part or all of the embodiments of the present application, and part or all of the modifications, replacements, alterations, splits, combinations, extensions, etc. of the embodiments are considered to be covered by the inventive idea of the present application, and belong to the protection scope of the present application, without creative efforts.

Any reference in this specification to "one embodiment," "an embodiment," "example embodiment," etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature or structure is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature or structure in connection with other ones of the embodiments.

The orientations or positional relationships indicated by "length", "width", "upper", "lower", "left", "right", "front", "rear", "back", "front", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, which may appear in the specification of the present application, are based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the embodiments of the present application and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present application. Like reference numbers and letters refer to like items in the figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance. In the description of the present application, "plurality" or "a plurality" means at least two or two unless specifically defined otherwise. In the description of the present application, it should also be noted that, unless explicitly stated or limited otherwise, "disposed," "mounted," and "connected" are to be understood in a broad sense, e.g., they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The above description is only for the specific embodiment of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. The terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A transmitter module, comprising:

a light emitting unit for emitting a light signal;

the light sensing sensor is used for detecting ambient light information; and

the control module comprises a power adjusting unit, and the power adjusting unit is used for adjusting the light emitting power of the light signal emitted by the light emitting unit according to the ambient light information detected by the light sensing sensor.

2. The transmitter module of claim 1, wherein the light emitting unit comprises a single light source or a plurality of light sources, and the light-sensing sensor and the light sources are packaged together in a package; or,

3. The transmitter module as claimed in claim 1, wherein an adjustment lookup table is preset, the adjustment lookup table includes a corresponding relationship between ambient light information and an adapted light emission power value, the power adjuster determines an adapted light emission power according to the ambient light information obtained by the light sensor and the corresponding relationship in the adjustment lookup table, and adjusts the light emission power of the light emitter according to the determined adapted light emission power value.

4. The transmitter module of claim 1, wherein the optical signal emitted by the light-emitting unit can be one or more of visible light, infrared light and near-infrared light.

5. The transmitter module as claimed in claim 1, wherein the light sensor is configured to sense a light intensity of a light signal in a scene as the ambient light information, and the power adjustment unit adjusts the light emitting power of the light signal emitted by the light emitting unit according to the sensed light intensity of the light signal.

6. The transmitter module of claim 1, wherein one or more different photosensitive channels are disposed in a path of the ambient light received by the photo sensor: the light-induced sensor comprises a visible light full-spectrum channel, a red light channel, a green light channel, a blue light channel, a wide-spectrum channel and/or an infrared light channel, and the light-induced sensor comprises light filters and photoelectric conversion elements corresponding to different light-induced channels.

7. The emission module of claim 1, wherein the light emitting unit comprises a single light source or a plurality of light sources, and the power adjusting unit adjusts the light emission power of the entire light emitting unit by correspondingly changing the light emission power of the individual light sources; or,

8. The transmitter module as claimed in any of claims 2 or 7, wherein the light source is any one or more of a vertical cavity surface emitting laser, an edge emitting laser, a light emitting diode, and a laser diode.

9. An optical detection device, comprising the transmitter module as claimed in any one of claims 1 to 8, and further comprising a receiver module for receiving the returned optical signal and outputting a corresponding sensing signal, and a processing module for deriving the related sensing information according to the sensing signal generated by the receiver module.

10. An electronic device comprising the optical detection apparatus as claimed in claim 9, wherein the electronic device further comprises an application module, and the application module is configured to implement a corresponding function according to the sensing information obtained by the optical detection apparatus.