Transmitter module, optical detection device and electronic equipment

Abstract

The present application provides a transmission module, including a light-emitting unit and a phase modulation element. The light-emitting unit is configured to transmit at least two first light signals. The phase modulation element is configured to receive the first light signal and output at least two second light signals accordingly. Each second light signal is obtained by modulating the phase of the corresponding first light signal by the phase modulation element. The present application also provides an optical detection device and an electronic device including the transmission module.

Description

Technical Field

[0001] The present application belongs to the field of distance measurement technology, and in particular relates to a transmitting module, an optical detection device and an electronic device. Background Art

[0002] The principle of Time of Flight (TOF) measurement is to calculate the distance of an object, or the depth of the surface of an object, and other three-dimensional information by measuring the flight time of a light signal in space. Due to the advantages of long sensing distance, high accuracy, and low energy consumption, TOF measurement 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 light signals into space, and the receiving module receives the carrier light signal returned from the object and senses the three-dimensional information of the object according to the time required from the transmission to the reception of the carrier light signal.

[0004] However, the power and phase of the light signal emitted by current optical detection devices are usually fixed and cannot be adjusted. The emission parameters of the light signal need to be designed to meet the measurement requirements of the longest distance within the ranging range. This results in a large portion of the light emission power being wasted in close-range sensing scenarios, which is not conducive to the endurance of the optical detection device and will also shorten the device life of the emission module. Summary of the invention

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

[0006] In a first aspect, the present application provides a transmitting module, comprising:

[0007] a light emitting unit configured to emit at least two first light signals; and

[0008] The phase modulation element is configured to receive the first optical signal and correspondingly output at least two second optical signals, wherein each second optical signal is obtained by modulating the phase of the corresponding first optical signal by the phase modulation element.

[0009] In an embodiment of the present application, the at least two second light signals are mutually coherent lights, and the at least two second light signals are projected toward an object in space. The phase modulation element adjusts the phase change amount of each first light signal before and after modulation to correspondingly change the pattern of each second light signal projected onto the object.

[0010] In an embodiment of the present application, the pattern includes a dot-matrix light spot pattern, a line-matrix stripe pattern or a floodlight pattern.

[0011] In an embodiment of the present application, the at least two second light signals are mutually incoherent lights, and the at least two second light signals project a floodlight pattern onto an object in space.

[0012] In an embodiment of the present application, the phase modulation element includes at least two optical channels, each beam of the first optical signal propagates in a corresponding optical channel, and the phase modulation element modulates the phase of the first optical signal light beam propagating in the corresponding optical channel by adjusting the optical path length of the light beam of the first optical signal in the corresponding optical channel and / or the refractive index of the corresponding optical path.

[0013] In an embodiment of the present application, the phase modulation element is one of a nano-optical chip, a liquid crystal optical phase modulator, and an optical waveguide phase modulator.

[0014] In a second aspect, the present application provides an optical detection device, comprising:

[0015] A launch module as described above;

[0016] A receiving module configured to receive the returned optical signal and output a corresponding sensing signal; and

[0017] The processing module is configured to obtain relevant sensing information according to the sensing signal.

[0018] In an embodiment of the present application, the transmitting module is configured to transmit the second optical signal into space to detect relevant information of an object in space, wherein at least part of the second optical signal is reflected back by the object to form a carrier optical signal, the optical signal received by the receiving module includes an optical signal of ambient light and the carrier optical signal, and the processing module is configured to determine the distance information of the object based on the time difference between the emission moment of the second optical signal and the sensing moment of the returned carrier optical signal.

[0019] In an embodiment of the present application, the processing module is configured to accumulate the counts of the sensing signals in corresponding time bins to generate a corresponding statistical histogram, and the optical detection device also includes a control module, which is configured to output a corresponding modulation control signal based on a comparison result between the highest sensing signal count value and a preset counting threshold range, and the phase modulation element controls the phase modulation of the first optical signal according to the modulation control signal, wherein the highest sensing signal count value is the sensing signal count value of the highest signal peak in the statistical histogram.

[0020] In an embodiment of the present application, the optical detection device is preset with a counting threshold range, and the control module is configured to output a corresponding modulation control signal when the highest sensing signal count value exceeds the counting threshold range, which includes: outputting a first modulation control signal when the highest sensing signal count value is less than a first counting threshold; and outputting a second modulation control signal when the highest sensing signal count value is greater than a second counting threshold; wherein the first counting threshold is the lower limit value of the counting threshold range, and the second counting threshold is the upper limit value of the counting threshold range, the phase modulation element is configured to receive the first modulation control signal and output a corresponding modulation signal to modulate the phase of the first light signal to increase the illumination concentration of the projected second light signal on the object, and the phase modulation element is configured to receive the second modulation control signal and output a corresponding modulation signal to modulate the phase of the first light signal to reduce the illumination concentration of the projected second light signal on the object.

[0021] In a third aspect, the present application provides an electronic device, comprising the optical detection device as described above, the electronic device further comprising an application module, wherein the application module is configured to implement corresponding functions according to sensing information obtained by the optical detection device.

[0022] Beneficial effects of this application:

[0023] When the optical transmission power of the transmitting module remains unchanged, the phase concentration of the pattern projected on the object is adjusted by phase modulation of the emitted second optical signal light beam through the phase modulation element, so that the emitted second optical signal can adapt to the requirements of different detection scenarios and reduce the overall power consumption of the optical detection device.

[0024] Although multiple embodiments are disclosed, including variations thereof, other embodiments of the present disclosure will be apparent to those skilled in the art from the following detailed description which shows and describes illustrative embodiments of the present disclosure. It will be appreciated that the present disclosure is capable of modification in various obvious aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings.

[0026] Figure 1 A schematic diagram of functional modules of an electronic device provided in one embodiment of the present application;

[0027] Figure 2 for Figure 1 A schematic diagram of functional modules of an embodiment of the optical detection device described in;

[0028] Figure 3 for Figure 2 A schematic diagram of functional modules of an embodiment of the transmitting module described in the embodiment;

[0029] Figure 4 for Figure 2 A schematic diagram of functional modules of another embodiment of the transmitting module described in;

[0030] Figure 5 for Figure 2 A schematic diagram of functional modules of another embodiment of the transmitting module described in;

[0031] Figure 6 for Figure 3-5 A schematic structural diagram of an embodiment of the phase modulation element described in;

[0032] Figure 7 for Figure 2 A schematic diagram of functional modules of an embodiment of a receiving module as described in the embodiment;

[0033] Figure 8 for Figure 2 A schematic diagram of functional modules of an embodiment of the control module described in;

[0034] Fig. 9 A schematic diagram showing the relationship between different signals of the optical detection device provided in an embodiment of the present application;

[0035] Fig.10 for Figure 1 A schematic diagram of functional modules of another embodiment of the optical detection device described in;

[0036] Fig.11 A schematic diagram of functional modules of an electronic device provided in another embodiment of the present application;

[0037] Fig.12 for Fig.10 and Fig.11 A schematic diagram of functional modules of an embodiment of the processing module described in the embodiment;

[0038] Fig.13 A statistical histogram of the optical detection device provided in an embodiment of the present application.

[0039] Fig.14 for Figure 1 A schematic diagram of functional modules of another embodiment of the optical detection device described in;

[0040] Fig.15 for Fig.14 A schematic structural diagram of another embodiment of the light beam scanning element described in . Specific embodiments

[0041] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limitations on the present application. In the description of the present application, it should be understood that the terms "first" and "second" are only used for description and cannot be understood as indicating or implying relative importance or implicitly indicating the number or arrangement order of the indicated technical features. Thus, the technical features defined as "first" and "second" may explicitly or implicitly include one or more of the technical features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0042] In the description of this application, it should be noted that, unless otherwise clearly specified or limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] The disclosure below provides many different embodiments or examples to implement the different structures of the present application. In order to simplify the disclosure of the present application, only the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the present application. In addition, the present application may reuse reference numerals and / or reference letters in different examples, and this repetition is to simplify and clearly state the present application, which itself does not indicate the specific relationship between the various embodiments and / or settings discussed. In addition, the various specific processes and materials provided in the description below are only examples for implementing the technical solutions of the present application, but those of ordinary skill in the art should be aware that the technical solutions of the present application may also be implemented by other processes and / or other materials not described below.

[0044] 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 so that the embodiments of the present application can be fully understood. However, those skilled in the art will appreciate that, even without one or more of the specific details, or adopting other structures, components etc., the technical scheme of the present application can also be put into practice. In other cases, known structures or operations are not shown or described in detail to avoid blurring the key points of the present application.

[0045] An embodiment of the present application provides a transmission module, which includes a light-emitting unit and a phase modulation element. The light-emitting unit is configured to emit at least two first light signals. The phase modulation element is configured to receive the first light signal and output at least two second light signals accordingly. Each second light signal is obtained by modulating the phase of the corresponding first light signal by the phase modulation element. Thus, by modulating the phase of the first light signal by the phase modulation element, the interference of the corresponding second light signal in the projected space can be changed.

[0046] Optionally, in some embodiments, at least two first light signals and corresponding at least two second light signals are coherent light, for example, they have the same polarization state, substantially the same wavelength or wavelength range, and maintain a stable phase difference during propagation. Thus, the at least two second light signals projected outward by the emission module can form a stably distributed interference enhancement area and interference cancellation area in space, and the part of the object located in the interference enhancement area will form a bright area with higher light intensity, and the part of the object located in the interference cancellation area will form a dark area with weaker light intensity. It can be understood that the distribution position of the interference enhancement area and the interference cancellation area can be adjusted by changing the initial phase between different beams of the second light signals through a phase modulation element, so that the pattern projected by the emission module on the object can be adjusted accordingly. For example: when the position of an object coincides with the positions of the interference enhancement area and the interference cancellation area, the second light signal can project a dotted light spot pattern or a linear stripe pattern with alternating light and dark on the object, that is, in this case, the light intensity projected by the second light signal on the object is non-uniformly distributed, and the illumination energy will be concentrated in the local area corresponding to the interference enhancement area; when the object is located outside the interference enhancement area and the interference cancellation area, the second light signal projects a floodlight pattern with uniformly distributed light intensity on the object.

[0047] Optionally, in some other embodiments, at least two of the second optical signals may be mutually incoherent, for example, having different polarization states or a phase difference that continuously changes during propagation. Thus, the at least two second optical signals projected outward by the emission module cannot form a stably distributed interference enhancement area and interference cancellation area in space, and in this case, the second optical signal projects a floodlight pattern with uniform light intensity distribution on the object.

[0048] Optionally, in some embodiments, the transmitting module transmits the second optical signal into space to sense the depth information, distance information, proximity information and other related sensing information of the object in the space. The second optical signal may be, for example, an optical pulse with a preset frequency. At least part of the emitted second optical signal is reflected back by the object in the space to form a carrier optical signal. The carrier optical signal can reflect the sensing information related to the depth information, distance information, proximity information and other related sensing information of the object, and the relevant sensing information of the object can be obtained by receiving and analyzing the carrier optical signal.

[0049] The embodiment of the present application also provides an optical detection device, which includes the transmitting module, receiving module and processor as described above. The receiving module is used to receive the optical signal and output the corresponding sensing signal, and the processing module obtains relevant sensing information according to the sensing signal generated by the receiving module, such as but not limited to obtaining one or more of the depth information, distance information and proximity information of the object.

[0050] 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.

[0051] It is understandable that, in addition to the carrier optical signal, the optical signal received by the receiving module may also include other optical signals that are not emitted by the transmitting module or are not reflected by an object, such as: optical signals of ambient light or optical signals emitted by other light sources in space.

[0052] Optionally, the sensing signal may be an electrical signal obtained by photoelectric conversion of the received optical signal. Optionally, the sensing signal may also be other types of signals, such as a magnetic signal, depending on the principle of conversion of the optical signal by the receiving module.

[0053] An embodiment of the present application also provides an electronic device, which includes 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, one or more of the related information such as proximity information, depth information and distance information of an object in space. Among them, the depth information can be used, for example, 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.

[0054] The optical detection device may be, for example, a laser radar, which may be used to obtain depth information or distance information of an object in space. The laser radar is used, for example, in the fields of intelligent driving vehicles, intelligent driving aircraft, 3D printing, VR, AR, service robots, etc. Taking an intelligent driving vehicle as an example, a laser radar is set in the intelligent driving vehicle, and the laser radar can scan the surrounding environment by quickly and repeatedly emitting a laser beam to obtain point cloud data reflecting the morphology, position and movement of one or more objects in the surrounding environment. Specifically, the laser radar emits a laser beam to the surrounding environment, and receives an echo beam reflected by each object in the surrounding environment. The position information of each object is determined by calculating the time delay (i.e., the flight time) between the emission time of the laser beam and the return time of the echo beam. At the same time, the laser radar can also determine the angle information describing the spatial orientation of the laser beam, combine the position information of each object with the angle information of the laser beam, and generate a three-dimensional map including each object in the scanned surrounding environment, and the three-dimensional map can be used to guide the intelligent driving of the unmanned vehicle.

[0055] Hereinafter, embodiments in which the optical detection device is applied to electronic equipment will be described in detail with reference to the accompanying drawings.

[0056] 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.

[0057] Reference Figure 1 and Figure 2The electronic device 1 includes an optical detection device 10. The optical detection device 10 can detect an object 2 in a space to obtain corresponding information of the object 2, such as but not limited to: one or more of proximity information of the object 2, depth information of the surface of the object 2, and distance information of the object 2 in the space.

[0058] The electronic device 1 may further 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 an 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 implementing 3D modeling, face recognition, machine vision, etc. based on the depth information of the surface of the object 2.

[0059] 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 transmit a light signal into space and receive a carrier light signal formed by reflection from an object 2 in space. The time difference between the time when the light signal is transmitted and the time when the carrier light signal is received is called the flight time t. The depth 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.

[0060] 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 carrier light signal.

[0061] In the following embodiments of the present application, the optical detection device 10 is mainly described as a DTOF measurement device as an example.

[0062] Optional, such as Figure 2As shown, the optical detection device 10 includes a transmitting module 12, a receiving module 14 and a control module 18. The transmitting module 12 is configured to transmit an optical signal into space to detect relevant information of an object in space, wherein at least part of the optical signal will be reflected back by an object 2 in space to form a carrier optical signal, and the carrier optical signal carries relevant sensing information of the object 2, such as but not limited to: depth information of the surface of the object 2, distance information of the object 2 in space, proximity information of the object 2, etc. At least part of the carrier optical signal can be received by the receiving module 14 to obtain sensing information of the object 2. The receiving module 14 is configured to receive the returned optical signal and output a corresponding sensing signal, the received optical signal includes an ambient light optical signal and the carrier optical signal, and the sensing signal is converted from the received optical signal.

[0063] Optional, such as Figure 3 As shown, in some embodiments, the transmitting module 12 includes a light-emitting unit 120 and a phase modulation element 122. The light-emitting unit 120 is configured to emit at least two first light signals. The phase modulation element 122 is configured to receive the first light signal and output at least two second light signals accordingly. The phase modulation element 122 modulates the phase of the first light signal to obtain the corresponding second light signal, and the initial phase of each second light signal when projected into space depends on the phase change of the corresponding first light signal before and after modulation by the phase modulation element 122. Therefore, the interference of the second light signal in space can be adjusted by the phase modulation of the corresponding first light signal by the phase modulation element 122. The energy distribution of the second optical signal in space changes accordingly with the change of the interference condition of the second optical signal in space. For example, for the same preset position in space, if the preset position is located in the interference enhancement area and the interference cancellation area of ​​the second optical signal, the energy distribution of the second optical signal at the preset position will be concentrated in the interference enhancement area. If the interference condition of the second optical signal changes so that the preset position is located outside the interference enhancement area and the interference cancellation area of ​​the second optical signal, correspondingly, the energy distribution of the second optical signal at the preset position will change from the original non-uniform distribution concentrated in the interference enhancement area to uniform distribution. It can be understood that, under the premise of the same optical emission power and the same divergence angle of the optical emission, the illumination power density per unit area of ​​the energy of the second optical signal in the case of non-uniform distribution will be greater than the illumination power density per unit area in the case of uniform distribution, but the area illuminated by the second optical signal in the case of non-uniform energy distribution will be smaller than the area illuminated in the case of uniform energy distribution.

[0064] Optionally, the light emitting unit 120 may include a light emitter 123 and a beam splitter 125. The light beam emitted by the light emitter 123 is divided into at least two first light signals by the beam splitter 125. Optionally, the light emitter 123 may be a light source in the form of a vertical cavity surface emitting laser (Vertical Cavity Surface Emitting Laser, referred to as VCSEL, which can also be translated as a vertical resonant cavity surface emitting laser), an edge emitting laser (Edge Emitting Laser, EEL), a light emitting diode (Light Emitting Diode, LED), a laser diode (Laser Diode, LD), etc. Among them, the edge emitting laser may be a Fabry Perot (Fabry Perot, FP) laser, a distributed feedback (Distribute Feedback, DFB) laser, an electro-absorption modulated laser (Electro-absorption Modulated, EML), etc., and the embodiment of the present application does not limit this. It can be understood that the light emitting unit 120 may include only a single light emitter 123, or may include a light emitter array composed of multiple light emitters 123.

[0065] It should be understood that the present embodiment does not specifically limit the wavelength or wavelength range of the first light signal emitted by the luminous body 123. Optionally, the light signal emitted by the luminous body 123 may be, for example, visible light, infrared light, near infrared light, or ultraviolet light.

[0066] Optionally, in some embodiments, at least two of the first optical signals are mutually coherent lights, for example, having the same polarization state, wavelength or wavelength band range, initial phase, etc.

[0067] Optionally, in some embodiments, at least two of the first optical signals may be polarized light.

[0068] Optional, such as Figure 4 As shown, the light emitting unit 120 may further include a collimating element 121. The collimating element 121 may be disposed between the beam splitting element 125 and the phase modulation element 122. The collimating element 121 is configured to collimate the light beam of the first light signal formed by the beam splitting element 125, so as to reduce the influence of different light beams of the first light signal overlapping each other during propagation on the accuracy of phase modulation. The collimating element 121 is, for example but not limited to, a collimating lens or a collimating lens group.

[0069] Optionally, in some other embodiments, the collimating element 121 may also be omitted, and the light beam emitted by the light emitting body 123 is split into at least two first light signals by the beam splitting element 125 and then directly received by the phase modulation element 122 .

[0070] Optional, such as Figure 5 As shown, the transmitting module 12 may further include a beam expander 124. The beam expander 124 is configured to expand the second optical signal beam output by the phase modulation element 122. For example, in some embodiments, the phase modulation element 122 includes a light input side 1220 and a light output side 1224, the light input side 1220 is arranged toward the light emitting portion 120 to receive the first optical signal emitted by the light emitting portion 120, and the beam expander 124 is arranged on the light output side 1224 of the phase modulation element 122 to expand the second optical signal output by the phase modulation element 122. It can be understood that the beam expander 124 can still maintain the coherence between the beams of the second optical signal unchanged after expanding the beam of the second optical signal. After expansion by the beam expander 124, the beam divergence angle of the second optical signal increases, so that the irradiation range of the second optical signal is expanded.

[0071] Optionally, in some other embodiments, the beam expander 124 may be omitted. The second optical signal emitted by the phase modulation element 122 may also be directly projected into space without passing through the beam expander 124 .

[0072] The phase modulation element 122 is configured to modulate the phase of each first optical signal to obtain each corresponding second optical signal. The initial phase of each second optical signal outputted can be adjusted by changing the phase change of each first optical signal.

[0073] Optionally, in some embodiments, the phase modulation element 122 includes at least two optical channels, and each of the first optical signals propagates in a corresponding optical channel. The phase of the light beam is positively correlated with the optical path of the light in the medium, and the phase of the light beam can be adjusted by changing the optical path of the light beam. According to the Fermat principle, the optical path s can be calculated using the following formula:

[0074]

[0075] Where m is the number of layers of uniform medium that the light path passes through, n i and l i are the refractive index of the i-th layer medium and the length of the optical path, respectively. Thus, the phase modulation element 122 can modulate the phase of the first optical signal light beam propagating in the corresponding optical channel by adjusting the optical path length and / or the refractive index of the corresponding optical path that the first optical signal light beam passes through in the corresponding optical channel. Figure 6As shown, in some embodiments, the phase modulation element 122 includes at least a first optical channel 1221, a second optical channel 1222, and a third optical channel 1223, wherein the first optical channel 1221 includes at least three sections of medium with refractive indices n11, n12, and n13, respectively. The second optical channel 1222 includes at least three sections of medium with refractive indices n21, n22, and n23, respectively. The third optical channel 1223 includes at least three sections of medium with refractive indices n31, n32, and n33, respectively.

[0076] Optionally, different optical channels of the phase modulation element 122 are independent of each other, and the light beams propagating in different optical channels do not interfere with each other. For example, in some embodiments, the phase modulation element 122 has the same number of optical channels as the number of light beams of the first light signal, and each of the first light signals propagates in a corresponding optical channel of the phase modulation element 122 to perform phase modulation.

[0077] Optionally, in some embodiments, the phase modulation element 122 can change the refractive index of the optical channel by a modulation signal to modulate the phase of the light beam passing therethrough. For example, the modulation signal can be an electrical signal or a magnetic signal, and the refractive index of the medium of the optical channel is changed by applying the electrical signal or the magnetic signal to the optical channel. It is understandable that the phase modulation element 122 can apply a uniform modulation signal to each optical channel to achieve phase modulation. Alternatively, each optical channel can also be divided into multiple sections, and the phase modulation element 122 applies an independent modulation signal to each section on an optical channel to achieve precise control of the modulated phase.

[0078] In an optional embodiment of the present application, the phase modulation element 122 can be, for example, a nano-optical chip, a liquid crystal optical phase modulator, an optical waveguide phase modulator, or other different types of optical phase modulators.

[0079] The phase modulation element 122 is configured to receive a modulation control signal, and send a modulation signal to the corresponding optical channel according to the received modulation control signal to control the phase modulation of the light beam propagating in the corresponding optical channel. The light beam of the first light signal is modulated by the phase modulation element 122 to form a light beam of the second light signal and projected into space. Optionally, in some embodiments, the modulation of the phase of the first light signal by the phase modulation element 122 may not change with time, that is, at least within a preset period of time, the phase change amount of the light beam of the first light signal after being modulated by the phase modulation element 122 is the same, so that the initial phase of the light beam of the second light signal is the same when projected outward or maintains a stable phase difference. As a result, the different light beams of the second light signal are mutually coherent light, and a stable interference distribution can be formed in space, for example, including an interference enhancement area and an interference cancellation area. In this case, if the object 2 is located exactly at the position where the interference enhancement area and the interference cancellation area are located in space, the light beam of the second light signal will project an interference pattern of alternating light and dark on the object 2.

[0080] It can be understood that by adjusting the phase change amount of the first light signal modulated by the phase modulation element 122, the interference distribution of the second light signal in space can be changed accordingly, for example, the position, size and shape of the interference enhancement area and the interference cancellation area can be changed accordingly. As a result, the interference pattern projected by the light beam of the second light signal on the object 2 also changes accordingly, for example, it is adjusted from a dot matrix spot pattern to a linear array stripe pattern. The dot matrix spot pattern corresponds to the case where the interference enhancement area is in a spot shape. The linear array stripe pattern corresponds to the case where the interference enhancement area is in a long and narrow stripe shape. The linear array stripe pattern can also be understood as the interference enhancement area gradually expanding from a spot shape, and the adjacent interference enhancement areas are connected to each other to form a long and narrow stripe shape. Due to the overall conservation of the projected light energy, the interference distribution of the second light signal in space will affect the distribution of its light energy density in space. The more concentrated the interference distribution is, the higher the light energy density in the interference enhancement area is, that is, the higher the light power density per unit area is. For example, the light energy distribution of the dot light spot pattern is more concentrated than that of the linear stripe pattern. Therefore, under the premise of the same light emission power and the same divergence angle of light emission, the light energy density at the light spot when the dot light spot pattern is projected is higher than the light energy density at the bright stripe when the linear stripe pattern is projected.

[0081] It is understandable that in some other embodiments, by phase modulating the projected light beam, the emitting module 12 can also project other types of patterns on the object 2, not limited to dot-matrix spot patterns and linear stripe patterns.

[0082] It can be understood that the interference enhancement area and the interference cancellation area formed by the second optical signal in space can also be distributed discontinuously, that is, the light waves of different light beams of the second optical signal cannot always just enhance or cancel each other in space, so that the second optical signal will form a flood illumination with uniform light intensity distribution at a position outside the interference enhancement area and the interference cancellation area, and project a flood pattern on the object 2 located at this position. The light energy of the second optical signal is uniformly distributed in the flood illumination area, so that the light energy density of the second optical signal in the flood illumination area is lower than the light energy density in the interference enhancement area where the light is concentrated. For example: the light energy density of the second optical signal in the flood illumination area is lower than the light energy density at the bright stripes when the linear stripe pattern is projected, and is lower than the light energy density at the light spot when the dot matrix spot pattern is projected.

[0083] The transmitting module 12 performs phase modulation on the first optical signal through the phase modulation element 122 to adjust the energy distribution of the projected second optical signal on the object 2, thereby improving the illumination power density of the local area on the object 2 by adjusting the energy distribution of the second optical signal on the object 2 without increasing the optical transmission power. For example, when the transmitting module 12 projects a dot matrix light spot pattern on the object 2, the illumination power density at the light spot is higher, when the linear array stripe pattern is projected on the object 2, the illumination power density at the bright stripe is second, and the illumination power density in the flood illumination area formed on the object 2 is lower.

[0084] Optionally, in some other embodiments, the modulation of the phase of the first light signal by the phase modulation element 122 may also vary with time, that is, the phase change of the light beam of the first light signal after being modulated by the phase modulation element 122 varies with time, so that the initial phase of the light beam of the second light signal also changes continuously with time when it is projected outward. As a result, the different light beams of the second light signal are mutually incoherent lights and cannot form a stable interference distribution in space. In this case, the second light signal can also form a floodlight with uniformly distributed light intensity in the projection space, so that a floodlight pattern can be projected on the object 2.

[0085] Optional, such as Figure 7 As shown, 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 the carrier light signal reflected by the object 2 to obtain sensing information related to the object 2, such as but not limited to the depth information of the surface of the object 2, the distance information of the object 2, the proximity information of the object 2, etc.

[0086] Optionally, in some embodiments, the photosensitive pixel 142 may include a single photon avalanche diode (SPAD), an avalanche photo diode (APD), a silicon photomultiplier (SiPM) 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.

[0087] 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.

[0088] Optionally, the receiving module 14 may further include a lens unit 144, which may be used to collimate or converge the carrier light signal reflected from the object 2 and transmit it to the photosensitive pixel 142 on the photoelectric sensor 140. The lens unit 144 may be a combination of multiple single lenses.

[0089] 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 spacing 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 spacing 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.

[0090] Optionally, the control module 18 can be used to control the emission of the optical signal by the light emitting unit 120 in the emission module 12, for example, it can be used to control the wavelength of the emitted optical signal, the position of the light emitting body 123 on the light emitting unit 120 that emits light in a time-sharing manner, the optical emission power of the light emitting body 123, etc. Optionally, as Figure 8As shown, in some embodiments, the control module 18 includes a transmission control unit 180, and the transmission control unit 180 is configured to control the transmission module 12 to transmit the second optical signal to space at a preset frequency. The second optical signal can be, for example, an optical pulse with a preset frequency.

[0091] Please also read Figure 8 and Fig. 9 In some embodiments, the emission control unit 180 may send an emission control signal to the light emitting unit 120 to control the light emitting unit 120 to emit a light signal. It is understandable that the emission control signal may be a drive signal applied to the drive circuit of the light emitting unit 120. Optionally, the emission control signal may be a series of control pulse signals with a preset frequency, 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 lit in the high-level segment to continuously emit light to the space, and stops emitting light in the low-level segment, thereby emitting a light pulse with a corresponding preset frequency as the first light signal. The phase modulation element 122 phase modulates the first light signal and then projects the corresponding second light signal into the space. Thus, within the timing corresponding to the high-level segment, the emission module 12 continuously emits a second light signal to the space, and at least part of the second light signal may be reflected back from the object 2 in the space to form the carrier light signal.

[0092] It is understandable that the emission frequency of the second light signal can be set according to the detection range of the optical detection device 10. For example, one emission cycle of the second light signal includes a light-emitting section and an extinguishing section, and the emission module 12 continuously emits the second light signal in the light-emitting section, and stops emitting light in the extinguishing section. The emission cycle of the second light signal needs to be greater than the maximum flight time corresponding to the detection range, so that the second light signal emitted in one emission cycle can effectively detect the object 2 within the detection range.

[0093] Optionally, in some embodiments, part or all of the functional units of the control module 18 may be integrated into the transmitting module 12 .

[0094] 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 turn on the photoelectric sensor 140 at the start time of each emission cycle of the second light signal to sense the returned photons. Thus, the receiving module 14 has a receiving cycle corresponding to the emission cycle of the second light 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.

[0095] Specifically, in some embodiments, the receiving control unit 182 is used to control the photosensitive pixel 142 to synchronously start sensing the returned photons at the start time of each emission cycle of the second 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. 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 the photon again in the next receiving cycle. Based on the above characteristics, the SPAD can generate a corresponding sensing signal in response to a returned photon in a receiving cycle. It is understandable that the SPAD may not be able to respond to the photon in a receiving cycle and does not generate a corresponding sensing signal, but regardless of whether it can respond to the photon, the SPAD will be reset before the end of a receiving cycle to restart sensing the received photon at the beginning of the next receiving cycle.

[0096] Optionally, in some embodiments, part or all of the functional units of the control module 18 may be integrated into the receiving module 14 .

[0097] Optional, such as Fig.10 As shown, in some embodiments, the optical detection device 10 may further include a processing module 15. The processing module 15 is, for example, configured to determine the distance information of the object 2 according to the time difference between the emission time of the second optical signal and the time when the returned carrier optical signal is sensed. However, it is not limited thereto. In other embodiments, the processing module 15 may also obtain relevant sensing information according to the received carrier optical signal and based on other suitable detection principles.

[0098] Optional, such as Fig.11 As shown, in some other embodiments, the processing module 15 may also be set at other locations in the electronic device 1 except the optical detection device 10. For example, the processing module 15 may be set on the main board of the electronic device 1, which is not limited in the present application.

[0099] like Fig.12 As shown, 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 is also configured to calculate the time difference between the moment when the receiving module 14 generates a sensing signal in response to the received photons within the receiving cycle and the starting moment of the receiving cycle, as a timestamp for the sensing signal.

[0100] Optionally, in some embodiments, the counting unit 152 is configured 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 SPAD can only respond to a single photon to generate a sensing signal in each receiving cycle, thereby accumulating one in one of the many time bins. Alternatively, the SPAD may not be able to receive any photons and not generate a sensing signal, thereby not accumulating in any time bin.

[0101] Optional, such as Fig.13 As shown, in some embodiments, the statistical unit 154 may be configured 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 may be a histogram circuit.

[0102] 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 detection scene. 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 sensing signal count corresponding to the carrier light signal reflected from the object 2 is superimposed on the noise background, so that the sensing signal count of the time bin corresponding to the carrier light signal will be significantly higher than the sensing signal count of other time bins, thereby 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 emitted light 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 highest signal peak with the highest sensing signal count is the flight time of the carrier light signal reflected by the object 2, and the depth information or distance information of the object 2 can be calculated based on it. 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 configured 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.

[0103] It is understandable that, according to the above sensing principle, the timestamp t0 of the carrier 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 second light signal transmission cycle. Therefore, it is impossible to distinguish the specific moment in the light segment of the transmission cycle from which the sensed carrier 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 segment in the transmission cycle. Optionally, in some embodiments, the duration of the light segment in the transmission cycle of the second 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 or 200ns, etc.

[0104] The photons of ambient light and the photons of the carrier light signal reflected from the object 2 have a certain probability of being received by the photosensitive pixels 142 of the receiving module 14, and then leaving the sensing signal count in the corresponding time bin. When the ambient light intensity is high, the noise background level of the sensing signal count in the statistical histogram is also correspondingly high, and the sensing signal count generated by the carrier light signal reflected from the object 2 is more likely to be submerged in the noise background caused by the ambient light. Therefore, it is necessary to increase the illumination power density of the second light signal on the object 2 accordingly to increase the sensing signal count value generated by the carrier light signal so that the signal peak can be more clearly prominent from the noise background caused by the ambient light, thereby improving the accuracy and confidence of peak finding during the detection process. However, if the light emission power of the light-emitting unit 120 is directly increased, the power consumption of the optical detection device 10 will increase. In this case, as mentioned above, the phase modulation element 122 can first be used to phase-modulate the first light signal to change the pattern projected by different light beams of the second light signal on the object 2, so as to increase the light power density of the second light signal per unit area of ​​the object 2 and increase the sensing signal count generated by the carrier light signal reflected from the object 2.

[0105] Optionally, in some embodiments, the optical detection device 10 may be preset with a counting threshold range, and the counting threshold range includes a first counting threshold and a second counting threshold, wherein the first counting threshold is the lower limit of the counting threshold range, and the second counting threshold is the upper limit of the counting threshold range. If the highest sensing signal count value corresponding to the highest signal peak is less than the first counting threshold, it means that the carrier light signal reflected back by the object 2 is insufficient, and the light power density of the second light signal per unit area of ​​the object 2 needs to be increased. If the highest sensing signal count value corresponding to the highest signal peak is greater than the second counting threshold, it means that the carrier light signal reflected back by the object 2 is surplus, and the light power density of the second light signal per unit area of ​​the object 2 needs to be reduced. If the highest sensing signal count value corresponding to the highest signal peak is within the counting threshold range, it means that the number of carrier light signals reflected back by the object 2 is appropriate, and the light power density of the second light signal per unit area of ​​the object 2 can be maintained.

[0106] Correspondingly, such as Figure 8As shown, the control module 18 may also include a phase modulation unit 183, and the phase modulation unit 183 is configured to output a corresponding modulation control signal according to the comparison between the highest sensing signal count value and the count threshold range to control the phase modulation of the first light signal by the phase modulation element 122. For example: when the highest sensing signal count value is less than the first count threshold, the first modulation control signal is output, and the phase modulation element 122 is configured to receive the first modulation control signal and output a corresponding modulation signal to modulate the phase of the first light signal to increase the illumination concentration of the projected second light signal on the object 2. When the highest sensing signal count value is greater than the second count threshold, the second modulation control signal is output, and the phase modulation element 122 is configured to receive the second modulation control signal and output a corresponding modulation signal to modulate the phase of the first light signal to reduce the illumination concentration of the projected second light signal on the object 2. It can be understood that the illumination concentration of the second optical signal on the object 2 can be defined according to the area of ​​the illuminated area of ​​the second optical signal on the object 2. For example, the smaller the illuminated area, the higher the illumination concentration and the higher the illumination power density; the larger the illuminated area, the lower the illumination concentration and the lower the illumination power density.

[0107] Optionally, in some embodiments, the illumination concentration can be respectively: dotted spot pattern, linear stripe pattern and flood pattern from high to low. It is understandable that the phase modulation element 122 can adjust the illumination concentration of the second light signal projected on the object 2 to a certain extent, for example, it can directly switch between the dotted spot pattern and the flood pattern.

[0108] It can be understood that if the distance of the object 2 is far or the ambient light noise level is high, the second light signal projected by the transmitting module 12 on the object 2 will be relatively weak, resulting in insufficient carrier light signal reflected back from the object 2. The technical solution provided in the present application can increase the light concentration of the second light signal on the object 2 through phase modulation of the phase modulation element 122 without increasing the light transmission power of the transmitting module 12, so as to correspondingly increase the probability of the reflected carrier light signal being received by the photosensitive pixel 142, thereby enhancing the signal peak intensity.

[0109] It can be understood that if the distance to the object 2 is relatively close or the ambient light noise level is low, the second light signal projected by the transmitting module 12 on the object 2 will be relatively strong, resulting in a relatively excessive carrier light signal reflected back from the object 2. The technical solution provided in the present application can reduce the light concentration of the second light signal on the object 2 through the phase modulation of the phase modulation element 122 without changing the light transmission power of the transmitting module 12, so as to reduce the interference of the excess carrier light signal on the detection, and at the same time increase the illuminated area of ​​the second light signal on the object 2, thereby improving the detection efficiency and frame rate.

[0110] Optionally, in some embodiments, the counting threshold range may be a counting range that is pre-stored and related to an ambient light noise level, and the ambient light noise level may be, for example, reflected as ambient light intensity. Specifically, a relationship table between the counting threshold range and the ambient light noise level is pre-set and stored. During detection, the optical detection device 10 senses the ambient light noise level and obtains a corresponding counting threshold range according to the ambient light noise level.

[0111] Optionally, in some embodiments, the ambient light noise level can be obtained based on a statistical histogram generated during the detection process. Specifically, during the detection process, the receiving module 14 generates a statistical histogram of the sensing signal counts in response to the photons of the ambient light and the photons of the carrier light signal reflected from the object 2. In the statistical histogram, except for the highest signal peak with the highest sensing signal count and a few other time bins with a large number of sensing signal counts, the sensing signal counts in most of the time bins are relatively close and have fewer count values. The sensing signal counts in these time bins reflect the ambient light noise level. The sensing signal counts in these time bins are averaged or averaged and multiplied by a correlation coefficient as the ambient light noise level value, and the corresponding counting threshold range can be obtained accordingly.

[0112] Therefore, the phase modulation unit 183 can generate a corresponding modulation control signal according to the currently detected statistical histogram, and feed it back to the phase modulation element 122, so that the phase modulation element 122 can modulate the second optical signal according to the modulation control signal, and realize autonomous dynamic adjustment to the optimal emission state that meets the actual detection scenario.

[0113] Optionally, in some other embodiments, in addition to being automatically adjusted according to the highest sensing signal count value fed back, the modulation control signal can also be manually adjusted through user intervention, so that the transmitting module 12 projects a second light signal pattern that is adapted to the detection scene on the object 2.

[0114] It is understandable that if the second light signal emitted by the emitting module 12 projects a non-uniformly distributed pattern on the object 2, such as a dot pattern or a linear pattern, the depth information or distance information of the dark area on the object 2 that is not illuminated by the second light signal cannot be effectively sensed, resulting in reduced sensing accuracy of the object 2. Fig.14 As shown, in some embodiments, the optical detection device 10 may further include a light beam scanning element 17. The light beam scanning element 17 may be configured to adjust the emission direction of the second light signal to change the bright area position of the pattern projected by the second light signal on the object 2, so that the bright area of ​​the projected pattern can scan and cover the entire object 2. Thus, even if the projected pattern is a pattern with a non-uniform distribution of light intensity, the second light signal can still scan and irradiate different parts of the object 2 to reduce the loss of sensing information caused by the lack of the returned carrier light signal in the parts of the object 2 that are not irradiated by the second light signal, thereby improving the accuracy of the optical detection device 10 in detecting the object 2.

[0115] Optionally, the beam scanning element 17 can optically adjust the direction of the second light signal emitted by the emission module 12. For example, in some embodiments, the beam scanning element 17 can be a micro-electro-mechanical system (MEMS) galvanometer, which can be configured to reflect the second light signal emitted by the emission module 12 to different angles by deflecting a micro-reflector. Alternatively, in some embodiments, the beam scanning element 17 can be an optical phased array (OPA), which adjusts the propagation angle of the second light signal by regulating the wavefront direction formed by different light beams in the second light signal.

[0116] Optional, such as Fig.15 As shown, the light beam scanning element 17 can also adjust the direction of the second light signal emitted by the emission module 12 by mechanical rotation. For example, in some embodiments, the light beam scanning element 17 is configured as a mechanical structure that drives the emission module 12 to rotate, thereby changing the direction of the second light signal emitted by the emission module 12. It is understandable that the embodiments of the present application do not limit the rotational freedom of the light beam scanning element 17.

[0117] It is understandable that, in some other embodiments, the light beam scanning element 17 may also be disposed inside the transmitting module 12. For example, the transmitting module 12 includes a light emitting unit 120, a phase modulation element 122, and a light beam scanning element 17. The light beam scanning element 17 may be disposed on a side where the phase modulation element 122 outputs the second light signal to optically adjust the emission direction of the second light signal. Alternatively, the light beam scanning element 17 is a mechanical mechanism for rotating the light emitting unit 120 and the phase modulation element 122.

[0118] It can be understood that if the light power density projected by the emission module 12 on the object 2 does not meet the requirements, the measured maximum sensing signal count value corresponding to the highest signal peak has exceeded the preset counting threshold range, for example: the second counting threshold greater than the upper limit of the preset counting threshold range or the first counting threshold less than the lower limit of the preset counting threshold range. In this case, the control module 18 can keep the light emission power of the light-emitting unit 120 unchanged and preferentially adjust the light concentration projected on the object 2 through phase modulation of the phase modulation element 122.

[0119] It is understandable that, in some embodiments, after the phase modulation element 122 has made a corresponding adjustment to the light concentration projected on the object 2 to the maximum extent, the second light signal emitted still cannot adapt to the detection scene, for example: the phase modulation element 122 has maximized the light concentration of the second light signal projected on the object according to the received first modulation control signal, and the highest sensing signal count value obtained is still less than the first counting threshold, or the phase modulation element 122 has minimized the light concentration of the second light signal projected on the object according to the received second modulation control signal, and the highest sensing signal count value obtained is still greater than the second counting threshold. In this case, the control module needs to adjust the light emission power of the light-emitting unit 120 so that the emitted second light signal adapts to the detection scene. To this end, if Figure 8 As shown, in some embodiments, the control module 18 may further include a power adjustment unit 184, which may be configured to adjust the light emission power of the light emitting unit 120. Optionally, the power adjustment unit 184 may adjust the light emission power of the entire light emitting unit 120 by correspondingly changing the light emission power of a single light emitter 123. Alternatively, the power adjustment unit 184 may adjust the light emission power of the entire light emitting unit 120 by changing the number of light emitters 123 emitting light on the light emitting unit 120, for example, starting a smaller number of light emitters 123 to work and emit light when a lower light emission power is required, and starting a larger number of light emitters 123 to work and emit light when a higher light emission power is required.

[0120] Specifically, in some embodiments, when the second light signal projected by the transmitting module 12 forms a dot matrix light spot pattern on the object 2, if the measured highest sensing signal count value is still less than the first counting threshold at the lower limit of the preset counting threshold range, the power adjustment unit 184 outputs a first power adjustment signal, and the light-emitting unit 120 receives the first power adjustment signal to increase the light emission power.

[0121] Similarly, in some embodiments, when the second light signal projected by the transmitting module 12 forms a floodlight pattern on the object 2, if the measured highest sensing signal count value is still greater than the second counting threshold at the upper limit of the preset counting threshold range, the power adjustment unit 184 outputs a second power adjustment signal, and the light-emitting unit 120 receives the second power adjustment signal to reduce the light emission power.

[0122] Therefore, the technical solution provided by the present application can reduce the emission of optical signals that meet the current scene by changing the optical emission power as much as possible under the premise of meeting the detection accuracy requirements. On the one hand, it can reduce the power consumption of the optical detection device 10, and on the other hand, it also provides an emission adjustment method of the emission module 12 that can adapt to more different detection scenes.

[0123] It is understandable that there may be multiple objects 2 at different distances in the space. If the light signal emission state of the entire emission module 12 is adjusted only according to one of the objects 2, it is likely that it cannot be adapted to other objects 2 at different distances. To this end, in some embodiments, the emission module 12 may include multiple light-emitting units 120, which correspond to multiple objects 2 at different distances in the space. Each light-emitting unit 120 projects multiple beams of the second light signal to the corresponding object 2. The emission of different light-emitting units 120 can be independently controlled, so that the parameters such as the light emission power, initial phase, and emission frequency of each light-emitting unit 120 projecting the second light signal can be adjusted in the aforementioned manner, so that each light-emitting unit 120 can meet the detection requirements related to the environment and the distance of the corresponding object 2. Optionally, in some other embodiments, if the emission module 12 includes only one uniformly controlled light-emitting unit 120, the optical detection device 10 can also adjust the emission of the light-emitting unit 120 for objects 2 at different distances in the space in turn and perform corresponding information detection.

[0124] In the description of this specification, the description with reference to the terms "one embodiment", "certain embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0125] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An optical detection device, characterized in that: include: Transmitter module, including: a light emitting unit configured to emit at least two first light signals; and a phase modulation element, configured to receive the first optical signal and output at least two second optical signals correspondingly, wherein each second optical signal is obtained by modulating the phase of the corresponding first optical signal by the phase modulation element; A receiving module is configured to receive the returned optical signal and output a corresponding sensing signal; a processing module is configured to obtain relevant sensing information according to the sensing signal; and The control module is configured to output a corresponding modulation control signal when the comparison result of the highest sensing signal count exceeds a preset count threshold range, including: When the highest sensing signal count value is less than a first count threshold, a first modulation control signal is output; and A second modulation control signal is output when the highest sensing signal count value is greater than a second count threshold; wherein the first count threshold is the lower limit value of the count threshold range, and the second count threshold is the upper limit value of the count threshold range, and the phase modulation element is configured to receive the first modulation control signal and output a corresponding modulation signal to modulate the phase of the first light signal to increase the illumination concentration of the projected second light signal on the object, and the phase modulation element is configured to receive the second modulation control signal and output a corresponding modulation signal to modulate the phase of the first light signal to reduce the illumination concentration of the projected second light signal on the object.

2. The optical detection device according to claim 1, characterized in that: The at least two second light signals are mutually coherent lights, and the at least two second light signals are projected toward an object in space. The phase modulation element adjusts the phase change amount of each first light signal before and after modulation to correspondingly change the pattern of each second light signal projected onto the object.

3. The optical detection device according to claim 2, characterized in that: The pattern includes a dot-matrix light spot pattern, a line-matrix stripe pattern or a floodlight pattern.

4. The optical detection device according to claim 1, characterized in that: The at least two second light signals are mutually incoherent lights, and the at least two second light signals project a floodlight pattern onto an object in space.

5. The optical detection device according to claim 1, characterized in that: The phase modulation element includes at least two optical channels, each of the first optical signals propagates in a corresponding optical channel, and the phase modulation element modulates the phase of the first optical signal light beam propagating in the corresponding optical channel by adjusting the optical path length of the first optical signal light beam in the corresponding optical channel and / or the refractive index of the corresponding optical path.

6. The optical detection device according to claim 1, characterized in that: The phase modulation element is one of a nano-optical chip, a liquid crystal optical phase modulator, and an optical waveguide phase modulator.

7. The optical detection device according to claim 1, characterized in that: The transmitting module is configured to transmit the second optical signal into space to detect relevant information of objects in space, wherein at least part of the second optical signal is reflected back by the object to form a carrier optical signal, the optical signal received by the receiving module includes the optical signal of ambient light and the carrier optical signal, and the processing module is configured to determine the distance information of the object based on the time difference between the emission moment of the second optical signal and the sensing moment of the returned carrier optical signal.

8. The optical detection device according to claim 7, characterized in that: The processing module is configured to accumulate and count the sensing signals in corresponding time bins to generate a corresponding statistical histogram, and the phase modulation element controls the phase modulation of the first optical signal according to the modulation control signal, wherein the highest sensing signal count value is the sensing signal count value of the highest signal peak in the statistical histogram.

9. An electronic device, characterized in that: The electronic device comprises the optical detection device as claimed in any one of claims 1 to 8, and further comprises an application module, wherein the application module is configured to implement corresponding functions according to the sensing information obtained by the optical detection device.

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