Detection Device and Method

Abstract

The present application provides a detection device and a detection method using the detection device. The device includes a light source, a receiving part, which includes a photoelectric conversion module. The receiving part further includes a first circuit for receiving a first modulation signal and a second circuit for receiving a second modulation signal. The controller can control the light source to emit irradiation light and generate a plurality of delay control phase signals with different phases. The first and second modulation circuits of the receiving part output electrical signals corresponding to at least one receiving control signal with the same phase. The information acquisition unit obtains the target information of the object to be detected based on the electrical signals of the receiving control signals with the same phase respectively obtained by the two circuits. This solution enables more efficient and accurate acquisition of the target information of the object to be detected by using multiple delay phase receiving control signals and the electrical signal values of the first and second circuits.

Description

Technical Field

[0001] This application relates to the field of detection technologies, and particularly to a detection device and method. Background Art

[0002] In the field of detection technologies, more and more technologies are being continuously introduced. To ensure the goal of efficient and rapid detection in application fields such as imaging or ranging, more and more devices are designed to have a structure with multiple taps (two or more). They can work in different time periods to read the photo-generated electrons generated in the pixel units connected thereto. When the multiple taps are reasonably arranged, efficient operation can be achieved within the chip or the receiving part formed thereby. However, there are deviations in the signals captured by different taps due to various factors. Even for the photo-generated electrons generated by the same incident return light, there are differences in the output values by different taps. This phenomenon will have an important impact on image acquisition or ranging.

[0003] In recent years, with the progress of semiconductor technologies, miniaturization of ranging modules for measuring the distance to an object has made progress. Therefore, for example, it has been possible to install a ranging module in a mobile terminal such as a so-called smart phone, which is a small information processing device with a communication function. With the progress of technology, in the process of detecting distance or depth information, the commonly used method is the time-of-flight ranging method (Time of flight, TOF). Its principle is to continuously send light pulses to the target object, and then use a sensor to receive the light returned from the object. The distance to the target object is obtained by detecting the flight (round-trip) time of the light pulse. In TOF technology, the technology for directly measuring the light flight time is called DTOF (direct-TOF); the transmitted light signal is periodically modulated, and the measurement technology for measuring the phase delay of the reflected light signal relative to the transmitted light signal and then calculating the flight time from the phase delay is called ITOF (Indirect-TOF) technology. According to the different types of modulation and demodulation methods, it can be divided into continuous wave (Continuous Wave, CW) modulation and demodulation method and pulse modulation (PulseModulated, PM) modulation and demodulation method. Furthermore, adopting the ITOF scheme can also obtain a high-precision and high-sensitivity distance detection scheme, so the ITOF scheme has also been more widely applied.

[0004] In order to obtain efficient measurement results and higher chip integration, a method with two or more taps is often used to achieve ranging. The distance information of the target object can be obtained according to the phase ranging algorithm. For example, the simplest two-phase method can be used, or the three-phase or four-phase method or even the 5-phase scheme can also be used to obtain the distance information. Taking a four-phase algorithm as an example, at least two exposures (usually four exposures are required to ensure measurement accuracy) are needed to complete the acquisition of four-phase data and output a frame of depth image. Therefore, it is difficult to obtain a high frame rate. At the same time, there are result differences as described above when different taps output information. In order to ensure the accuracy of the results during ranging or image acquisition, a solution to solve the above problems is urgently needed. Summary of the Invention

[0005] An object of the present application is to provide a detection device and method for solving the technical problem that the detection distance of the existing detection device is not far enough, aiming at the deficiencies in the above-mentioned prior art.

[0006] To achieve the above object, the technical solutions adopted in the embodiments of the present application are as follows:

[0007] In a first aspect, an embodiment of the present application provides a detection device, including: a light source operable to emit light to illuminate the object to be detected;

[0008] a receiving part having a photoelectric conversion module, the receiving part being configured to obtain the light quantity of the light source reflected by the object to be detected, and the photoelectric conversion module being operable to generate corresponding photo-generated electrons according to the received light quantity;

[0009] The receiving part further includes a first circuit and a second circuit for converting incident light into respective electrical signals. The first circuit is configured to receive a first modulation signal, and the second circuit is configured to receive a second modulation signal. The first circuit and the second circuit are configured to generate respective electrical signals according to the first modulation signal and the second modulation signal;

[0010] a controller electrically connectable to the light source to emit light to illuminate the object to be detected. At the same time, the controller is also electrically connectable to the receiving part. The receiving part can receive a plurality of receiving control signals in the same phase or different phases as the light emission signal of the light source, and obtain electrical signals corresponding to at least one receiving control signal with the same phase through the two circuits;

[0011] an information acquisition unit operable to obtain the target information of the object to be detected according to the electrical signals of the receiving control signals with the same phase respectively obtained by the two circuits.

[0012] Optionally, the plurality of receiving control signals in the same phase or different phases as the light emission signal of the light source are four receiving control signals with different phases.

[0013] Optionally, during the operation of obtaining the target information, the electrical signals corresponding to the in-phase reception control signal are at least subjected to a summation process.

[0014] Optionally, the multiple reception control signals of in-phase or out-of-phase include four phase signals of 0°, 90°, 180°, and 270°. The optical reception unit obtains the electrical signals corresponding to the reflected light of the same phase through two circuits for at least one of the phase reception control signals.

[0015] Optionally, the two circuits respectively obtain different electrical signals corresponding to each phase of the multiple reception control signals of in-phase or out-of-phase.

[0016] Optionally, the first modulation signal is inverse to the second modulation signal during at least a partial time period.

[0017] Optionally, the light source outputs at least four emission lights of the same duration, and the circuit modulation signals corresponding to the two reception control signals with a phase difference of 180° are inverse signals.

[0018] Optionally, there is a first time interval between the circuit modulation signals corresponding to the two reception control signals with a phase difference of 90°, and both are converted into different electrical signals by the first circuit and the second circuit that receive the first modulation signal and the second modulation signal in the reception unit.

[0019] Optionally, the first circuit and the second circuit are connected to the same pixel unit, receive the first modulation signal and the second modulation signal, and generate their respective electrical signals.

[0020] Optionally, the reception unit includes a plurality of pixel units arranged in an array.

[0021] In a second aspect, an embodiment of the present application provides a detection method, which is applied to the detection device described in the first aspect above. The detection method includes:

[0022] The reception unit obtains the light quantity of the light source reflected by the object to be detected under the control of the control signal. The photoelectric conversion module in the reception unit can generate corresponding photo-generated electrons according to the received light quantity;

[0023] The reception unit further includes a first circuit and a second circuit for converting incident light into their respective electrical signals. The first circuit is configured to be controlled by receiving the first modulation signal, and the second circuit is configured to be controlled by receiving the second modulation signal. The first circuit and the second circuit are configured to generate their respective electrical signals according to the first modulation signal and the second modulation signal;

[0024] A controller controls a light source to emit light for illuminating the object to be detected. Meanwhile, the controller can also control the receiving unit. The receiving unit can receive multiple receiving control signals that are in the same phase or different phases as the light signal emitted by the light source, and obtain electrical signals corresponding to at least one receiving control signal in the same phase through the two circuits respectively.

[0025] An information acquisition unit can obtain the target information of the object to be detected based on the electrical signals of the receiving control signals in the same phase obtained by the two circuits respectively.

[0026] Optionally, the multiple receiving control signals that are in the same phase or different phases as the light signal emitted by the light source are four receiving control signals with different phases.

[0027] Optionally, during the operation of obtaining the target information, the electrical signals corresponding to the receiving control signals in the same phase are at least subjected to a summation process.

[0028] Optionally, the multiple receiving control signals that are in the same phase or different phases include four phase signals of 0°, 90°, 180°, and 270°. The light receiving unit obtains electrical signals corresponding to the reflected light in the same phase through the two circuits respectively for at least one of the phase receiving control signals.

[0029] Optionally, the two circuits respectively obtain different electrical signals corresponding to each phase of the multiple receiving control signals that are in the same phase or different phases.

[0030] Optionally, the first modulation signal is inverse to the second modulation signal in at least part of the time period.

[0031] Optionally, the light source emits light with the same duration at least four times, and the circuit modulation signals corresponding to the two receiving control signals with a phase difference of 180° are inverse signals.

[0032] Optionally, there is a first time interval between the circuit modulation signals corresponding to the two receiving control signals with a phase difference of 90°, and both are converted into different electrical signals by the first circuit and the second circuit in the receiving unit that receive the first modulation signal and the second modulation signal.

[0033] Optionally, the first circuit and the second circuit are connected to the same pixel unit, receive the first modulation signal and the second modulation signal, and generate their respective electrical signals.

[0034] Optionally, the receiving unit includes a plurality of pixel units arranged in an array.

[0035] The beneficial effects of this application are:

[0036] A detection device and method provided by an embodiment of the present application. The detection device includes: a light source operable to emit light to illuminate an object to be detected;

[0037] A receiving part having a photoelectric conversion module, the receiving part being configured to obtain the amount of light of the light source reflected by the object to be detected, and the photoelectric conversion module being operable to generate corresponding photo-generated electrons according to the received amount of light; the receiving part further includes a first circuit and a second circuit for converting incident light into respective electrical signals, wherein the first circuit is configured to receive a first modulation signal, the second circuit is configured to receive a second modulation signal, and wherein the first circuit and the second circuit are configured to generate respective electrical signals according to the first modulation signal and the second modulation signal; a controller electrically connectable to the light source to emit light to illuminate the object to be detected, and at the same time the controller is also electrically connectable to the receiving part, the receiver being operable to receive a plurality of reception control signals in phase or out of phase with the light signal emitted by the light source, and obtaining electrical signals corresponding to at least one reception control signal with the same phase through the two circuits respectively; an information acquisition unit operable to obtain target information of the object to be detected according to the electrical signals of the reception control signals with the same phase respectively obtained by the two circuits. In this way, electrical signals corresponding to at least one reception control signal with the same phase are respectively obtained by the two circuits in the receiving part, that is to say, for the completely same emitted light, after being reflected by the target, it is received by different circuits. It can be understood that it is obtained by different taps and arithmetic processing is performed in subsequent circuits. Finally, certain arithmetic operations, including difference and other schemes, can be performed using the electrical signal values of the same signal twice, so as to obtain more accurate information ultimately, so that the accuracy of the detector in obtaining the quality of the image or the measured distance is maximally improved. Description of the Drawings

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0039] Figure 1 A schematic diagram of the functional modules of a detection device provided by an embodiment of the present application;

[0040] Figure 2 A schematic diagram of the operation of a receiving part provided by an embodiment of the present application;

[0041] Figure 3 A schematic diagram of the operation of an information acquisition unit provided by an embodiment of the present application;

[0042] Figure 4A schematic diagram of a control timing diagram provided by an embodiment of the present application;

[0043] Figure 5 Another schematic diagram of a control timing provided by an embodiment of the present application;

[0044] Figure 6 Another schematic diagram of a control timing provided by an embodiment of the present application;

[0045] Figure 7 A schematic flowchart of a detection method provided by an embodiment of the present application;

[0046] Figure 8 Another schematic flowchart of a detection method provided by an embodiment of the present application;

[0047] Figure 9 Another schematic flowchart of a detection method provided by an embodiment of the present application. Detailed implementation manners

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. The components of the embodiments of the present application usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0049] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0050] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0051] Figure 1 A schematic diagram of the functional modules of a detection device provided by an embodiment of the present application. As Figure 1As shown, the detection device includes: a light source 110, a controller 120, a receiving unit 130, and an information acquisition unit 140. The light source 110 can be configured as a unit or an array light source system that emits continuous light. It can be a semiconductor laser, an LED, or other light sources that can be pulse-modulated. When a semiconductor laser is used as the light source, a vertical-cavity surface-emitting laser (VCSEL) or an edge-emitting laser (EEL) can be adopted. Here, it is only for illustrative purposes and not specifically limited. The waveform of the light output by the light source 110 is also not limited and can be a square wave, a triangular wave, a sine wave, etc. The receiving unit 130 includes a photoelectric conversion module, which has a photoelectric conversion function and can be implemented by a photodiode (PD). It can specifically be a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). Here, its type is not specifically limited either.

[0052] The controller 120 controls the light source to emit light a different number of times. The receiving unit 130 obtains the light reflected back by the object to be detected 150 corresponding to different phase delays at four values of the phase difference delay between the controller 120 and the emitted light of the light source 110 being 0°, 180°, 90°, and 270° respectively when the light source 110 emits light. The reflected light forms incident light in the receiving unit 130, and then different information is generated through the photoelectric conversion of the receiving unit. In some cases, the information of the object to be detected is also obtained using a two-phase scheme of 0° and 180°. Some documents have also disclosed a three-phase scheme of 0°, 120°, and 240° to obtain target information. Even some documents have disclosed a five-phase difference delay scheme. The present invention is not specifically limited. The target information obtained can be the image information of the target, or the distance information, contour information, etc. of the target. The present invention is not specifically limited either. Hereinafter, taking the four-phase time-of-flight distance acquisition scheme as an example to specifically elaborate on the existing problems and solutions for illustrative technical problems, the multi-tap structure can have an independent tap for each phase. Four phase taps are connected to a pixel unit (which can be directly connected or connected through an intermediate medium). It can also be that two phases share one tap. For example, 0° and 90° share one tap, and 180° and 270° share one tap. Such a design can not only achieve the purpose of reliable information transmission but also further ensure the optimization of the pixel size design and layout structure. The multi-tap connection on one pixel achieves the effect of efficiently obtaining target information (such as distance, depth, contour, or image, etc.).

[0053] On the basis described above, the light source 110 emits emitted light. The receiving unit 130 is controlled by the controller 120 to obtain the light reflected by the object to be detected 150 at a predetermined delay phase with respect to the emitted light, for example, four different delay phases. The returned reflected light forms incident light in the receiving unit 130. There are no special requirements for the light source. The light emitted by the light source each time is the same light without phase difference, avoiding errors caused by the need to adjust the light-emitting state parameters during the use of the light source device. Moreover, the implementation of the device is very simple, ensuring the reliability of the entire detection device system. In this solution, the implementation of the phase delay is achieved within the receiving unit and the controller. The controller can be integrated in the receiving unit, ensuring the simplicity and efficiency of the system structure. Additionally, the multi-phase delay receiving scheme adopted in the receiving unit also avoids the need to emit emitted light for each phase at the transmitting end. For example, in the four-phase scheme, we can obtain the object information with two phase delays of 0° and 180° in one emission, enabling the entire ranging system to achieve the goal of efficient ranging. The light emitted by the light source 110 and reflected by the object to be detected 150 is converted into photo-generated electrons (or photo-generated charges) in the photoelectric conversion module of the receiving unit. The photo-generated electrons are modulated by the taps and transfer charges in part according to the first circuit or the second circuit inside the device (the first circuit or the second circuit mentioned here includes the charge or electron transfer channels inside the pixel). They are respectively transmitted to different external physical circuit parts (the first circuit or the second circuit also includes the first physical circuit part and the second physical circuit part outside the pixel) through the first electron transfer channel or the second electron transfer channel inside the pixel. Then, physical operations (such as using charge storage units: capacitors, etc.) or digital operations (such as integrating the sensor and the operation unit into a single-chip structure) are performed inside the pixel, or physical or digital operations are performed in the subsequent ADC or other circuit parts. The present invention does not limit the specific implementation scheme.

[0054] Take a four-phase two-tap structure as an example for explanation, where 0° and 90° share a tap, and 180° and 270° share a tap (however, in specific operations, sharing a tap does not mean sharing a fixed tap, and the taps shared by two phase delays can be interchanged). The controller 120 controls the light source 110 to emit light, which is reflected by the detected object 150. The controller 120 controls the receiving unit 130 to receive light with two phase delays, for example, the two phase delays of 0° and 180° in the above four phases are received. The photoelectric conversion module in the receiving unit 130 converts the delayed phase light signal into photogenerated electrons in the pixel. The tap of the first circuit receives the first modulation signal, transfers the photogenerated electrons converted by the photoelectric conversion module at the 0° phase in the pixel, and forms an electrical signal. This electrical signal is output by the first circuit, and the tap of the second circuit receives the second modulation signal, transfers the photogenerated electrons converted by the photoelectric conversion module at the 180° phase in the pixel, and forms an electrical signal. This electrical signal is output by the second circuit. It is also possible to have a tap corresponding to each phase delay. In the first circuit, 0° and 90° share a floating diffusion node (FD), while 180° and 270° share a floating diffusion node (FD). However, in specific operations, sharing a floating diffusion node does not mean sharing a fixed floating diffusion node. The floating diffusion nodes shared by the two phase delays can be interchanged. In this embodiment, the electrical signals corresponding to the 0° and 180° phase delays can be obtained in one light source emission, and in the next control of the controller, the two phase delays of 90° and 270° in the four phases are received, and the photoelectric conversion module in the receiving unit 130 converts the delayed phase light signal into photogenerated electrons in the pixel. The tap of the first circuit receives the first modulation signal, and transfers the photogenerated electrons converted by the photoelectric conversion module at the 90° phase in the pixel to form an electrical signal, which is output by the first circuit. The tap of the second circuit receives the second modulation signal, and transfers the photogenerated electrons converted by the photoelectric conversion module at the 270° phase in the pixel to form an electrical signal, which is output by the second circuit. In this mode, the information corresponding to 90° and 270° is obtained at one time.The last controller 120 can also control the light source 110 to output emitted light, and at least control the reception with two phase delays of 0° and 180° in the four phases. The photoelectric conversion module in the receiving unit 130 converts the delayed-phase optical signal into photo-generated electrons in the pixel. The tap of the first circuit receives the first modulation signal, transfers the photo-generated electrons converted from the 180° phase in the pixel, and forms an electrical signal, which is output by the first circuit. The tap of the second circuit receives the second modulation signal, transfers the photo-generated electrons converted from the 0° delayed phase in the pixel, and forms an electrical signal, which is output by the second circuit. Thus, the effect that two circuits respectively obtain electrical signals corresponding to at least one same-phase reception control signal is achieved. In the process of performing the final target information calculation, the at least two electrical signals obtained by the two circuits can be calculated to obtain the target information. For example, for image or distance information, the signals obtained by the two circuits can be used for the following calculation:

[0055] f(0°) = mf(0°_1) + nf(0°_2);

[0056] f(180°) = lf(180°_1) + hf(180°_2); (1)

[0057] The 90° and 270° delay phase results are obtained through a similar scheme, and can be corrected by performing an operation similar to Equation (1), and the corrected result is used in the final acquisition of the target information. The corrected result can be the process result in the detection by the detection device, or can be directly used in the specific expression of the final image or distance calculation. The present invention does not limit the specific implementation manner. In the formula, f(0°) refers to the final information result corresponding to the 0° phase to be corrected, f(0°_1) refers to the information result corresponding to the 0° phase obtained by the first circuit, f(0°_2) refers to the information result corresponding to the 0° phase obtained by the second circuit, where m, n, l, h can be correction coefficients taking values in the range of [-1, 1].

[0058] In the above embodiments, the received phases with phase delays of 0° and 180° have a phase difference of 180°; the modulation signals corresponding to the two delayed received phases in the first circuit and the second circuit are inverse signals. That is, when the received signal with a 0° phase delay outputs an electrical signal through the first circuit or the second circuit during the first time period, the received signal with a 180° delay corresponding to the pixel does not output an electrical signal through any of the above two circuits, and the opposite operation is performed during another time period. The same operation is also performed on the received phases with phase delays of 90° and 270° whose phase difference is 180°. In this way, a scheme is obtained in which the circuit modulation signals corresponding to the received phases with a phase difference of 180° are inverse signals, achieving the effects of obtaining signal reliability and efficient system operation when multiple phases share taps or floating diffusions (FD) or other circuit elements. When obtaining the phase information with a phase difference of 90°, there is a first time interval, which is the autonomous adjustment time interval within the system and can be designed in coordination with the reset timing to ensure the reliability of the output of different phase signal results.

[0059] The following further explains the technical problems and solutions existing in multiple taps in TOF ranging. When distributing charges to the first tap and the second tap according to the distance to the object, by using all eight detections (for each phase signal, electrical signals corresponding to the phase delay are obtained through two circuits), the signal performs an operation to calculate the depth representing the distance to the object. Different-phase electrical information, such as the accumulated charge quantity signal, can be output through two different circuits. During the distance acquisition process, the phase difference of the optical signal traveling back and forth between the lidar and the target can be calculated based on the 4 groups of integrated charges. Taking sinusoidally modulated light as an example, the phase difference between the echo signal corresponding to the modulated light and the transmitted signal is:

[0060]

[0061] In Equation 2 above, Q 0° , Q 90° , Q 180° , Q 270° are the electrical signals converted by the receiving circuit corresponding to different phase delays respectively. Combining the relationship between the distance and the phase difference, the final distance result can be obtained:

[0062]

[0063] In Equation 3 above, c is the speed of light and f is the laser frequency emitted by the light source 110. For the case where the light emitted by the light source 110 is a square wave, it can be divided into different situations, and the final distance information is obtained according to the following calculation method:

[0064] When Q 0° > Q180° and Q 90° >Q 270° when

[0065]

[0066] When Q 0° <Q 180° and Q 90° >Q 270° when

[0067]

[0068] When Q 0° <Q 180° and Q 90° <Q 270° when

[0069]

[0070] When Q 0° >Q 180° and Q 90° <Q 270° when

[0071]

[0072] In Equation 4-7 for calculating the distance of the above square wave, Q 0° , Q 90° , Q 180° , Q 270° are respectively the electrical signals converted by the receiving circuit corresponding to different phase delays. c is the speed of light, and f is the laser frequency. Of course, in some special cases, some companies directly use the sine wave method to approximately calculate the distance of the square wave. During the four-phase ranging process, it involves the results of different phase delay signals output by different circuits (including the internal charge transfer channel of the pixel and the external physical circuit part of the pixel). However, in the actual use process, due to the influence of the delay and offset of the column line and the comparator, etc., there are also differences in the results obtained by the two circuits for processing the same phase received signal. For example, classifying these influences into Q 0° , Q 180° , the inherent deviation electron numbers are △Q1 and △Q2. Then, in reality, there are certain deviations in the electron numbers obtained by Q 0° , Q 180° . For example, the electrical signals corresponding to the four phase delays obtained by the first circuit and the second circuit respectively are:

[0073] Q 0°，r1 = Q 0° + △Q1; Q 180°，r2 = Q 180° + △Q2; (8)

[0074] Q in Equation 8 0°，r1 refers to the value of the electrical signal obtained by converting the 0° delay phase actually substituted into the distance calculation formula through the first circuit. Q 0° refers to the ideal calculated true value obtained without considering the differences between the first circuit and the second circuit under ideal conditions. △Q1 refers to the deviation electrical signal value generated when the first circuit converts the 0° delay phase signal. The meanings of the symbols in the electrical signal calculation formula corresponding to the 180° delay phase in Equation 8 are similar to those in the 0° delay phase calculation formula, and will not be elaborated here. The value of △Q1 can be a linear function relationship or a polynomial function relationship, and this value can be simulated according to the actual situation. This deviation electrical signal is very difficult to obtain in actual use. Therefore, substituting the actual values of the electrical signals converted by different delay phases through different circuits into the distance solution formula under this condition will cause a certain deviation, resulting in inaccurate final distance calculation. In the solution of the present invention, to solve this technical problem, two electrical signal values can be obtained for each of the four different delay phases by the first circuit and the second circuit respectively, and then the arithmetic mean scheme (or a similar algorithm) is used to obtain the electrical signal value finally substituted into the expression, which can be expressed by the following formula:

[0075]

[0076] That is, the signals obtained by the two circuits are subjected to addition operation. After the addition operation, the results obtained by the outputs of the same phase in different circuits are superimposed. On this basis, the influencing factors △Q1 and △Q2 are also superimposed. Therefore, the differences in the outputs of the same phase of different circuits are considered in the result, and using the superimposed result for subsequent distance calculation can obtain an accurate distance result. Taking the case of Equation 4 with square wave detection as an example:

[0077] When Q 0° >Q 180° and Q 90° >Q 270° then

[0078]

[0079] In the above formula (10), in the final distance acquisition, the sum result can be directly used without averaging to obtain the final accurate distance information. The implementation can be achieved through the result of physical capacitance charge accumulation or through digital operations in subsequent arithmetic circuits. In the calculation, since the subtraction operation of different phases is involved, the offset caused by the column comparator, etc., can be eliminated. On the other hand, the transfer function mismatch phenomenon caused by non-ideal factors such as tapping can also be removed. The deviation charge caused by the transfer function mismatch can also be classified into linear or non-linear relational expressions. Its fundamental principle is similar to the charge difference caused by the offset, and a scheme similar to using the values obtained from two channels in image sensing applications to correct and obtain the most accurate value, such as the previous relational expression (1), can also be adopted.

[0080] Figure 2 FIG. shows a schematic diagram of the internal signal transmission and connection relationship of a receiving unit 130. The receiving module 130 internally includes a first circuit and a second circuit. The first circuit can receive a first modulation signal. Under the control of this signal, the photo-generated electrons generated by the photoelectric conversion module inside the receiving unit 130 can be transferred by the first circuit to form a first electrical signal. As previously described, the first circuit includes an electron transfer channel inside the pixel unit and a physical circuit part outside the pixel unit. The first modulation signal can be a physical device or apparatus in the first circuit, such as a modulation gate, and is a modulation signal generated by a controller, which realizes the transfer of different photo-generated electrons by the first circuit or the second circuit to form corresponding electrical signals. The basic principle of the second modulation signal acting on the second circuit is similar to that of the first circuit and will not be elaborated here. Of course, the same pixel can also be connected to more circuits to obtain more electrical signals, which will not be elaborated here either. The above-mentioned first circuit and second circuit can be directly connected to the same pixel unit. Through the time-sharing output of the pixel unit, more pixels can detect the object to be detected, ensuring the accuracy of detection. In addition, multiple such pixels form the entire pixel array to achieve efficient detection and targeted detection, and can also achieve simultaneous detection of multiple targets.

[0081] Figure 3Fig. shows a schematic diagram of obtaining the result information of the detected object 150 through electrical signals obtained by different circuits (here, two circuits, namely the first circuit and the second circuit, are taken as examples for illustration, but the specific implementation is not limited to only two circuits outputting signals). The first electrical signal may include electrical signals output by the first circuit corresponding to different phase delays. For example, the first electrical signal may include four electrical signals corresponding to four phase delays of 0°, 90°, 180°, and 270°. Similarly, the second electrical signal may also include four electrical signals corresponding to four phase delays of 0°, 90°, 180°, and 270°. The information acquisition unit 140 acquires the final target information according to the electrical signals corresponding to at least one same-phase reception control signal obtained by the first circuit and the second circuit, where at least one same-phase reception control signal may be any one or more of the above four phases. The four-phase method can be used to achieve the high efficiency of ranging, and the method shown in Equation 1 can also be used to correct at least part of the information obtained in the entire pixel array to obtain the information required for calculating the final target information (distance or image, etc.). That is, the first electrical signal and the second electrical signal can be used in the calculation process of the final target information or can directly calculate the final target information in a physical or digital manner according to the four-phase method ranging formula described above. Here, it is not limited that the electrical signals obtained by the first circuit or the second circuit are directly used for the target information of the detected object to be directly used for the final operation.

[0082] Figure 4 and Figure 5 Fig. shows a schematic diagram of using the light source 110 to emit square emission light for detection. Taking two phases and two taps as an example for illustration, in Figure 4 and Figure 5 401 and 501 represent the emission light emitted by the light source twice, and 402 and 502 represent the echo signals obtained after the emission light is reflected by the target. Q 0°,r1 represents the first electrical signal corresponding to the 0° phase delay output by the first circuit, Q 180°,r2 represents the second electrical signal corresponding to the 180° phase delay output by the second circuit, Q 0°,r2 represents the second electrical signal corresponding to the 0° phase delay output by the second circuit, Q 0°,r1 represents the first electrical signal corresponding to the 180° phase delay output by the first circuit. It can be clearly seen from Figure 4 and Figure 5 that the 0° delay phase refers to the receiver control signal controlled by the controller 130 that has no delay with the emission light. Other delay phases have the same meaning as 0°. The four obtained electrical signals are processed in the information acquisition unit 140, and the final target information can be obtained according to the method described above.

[0083] Figure 6 A timing diagram is shown to implement two circuits to respectively obtain a first signal and a second signal corresponding to different phases based on a four-phase basis. Here, the exposure time refers to the duration during which the receiving unit receives the light reflected back by the object to be detected 150. The FD reset time refers to the time for initializing and resetting a pixel after the pixel receives the reflected light during the exposure time, converts it into photo-generated electrons through the photoelectric conversion unit, and then transfers and outputs an electrical signal through the first circuit or the second circuit. The emitted laser refers to emitting light at a certain frequency. Here, a square wave is taken as an example for illustration. In fact, waveforms such as sine waves and triangular waves can be emitted, Q 0°,r1 、Q 180°,r2 、Q 90°,r1 、Q 270°,r2 、Q 0°,r2 、Q 180°,r1 、Q 90°,r2 、Q 270°,r1 and Figure 4 and Figure 5 have similar meanings here and will not be explained one by one. The four-phase scheme can achieve high efficiency during the ranging process. By combining the present invention to correct the obtained value for at least one phase, or using the first electrical signal and the second electrical signal output by two channels of each phase among the four phases, the distance information of the object to be detected can be accurately obtained using the aforementioned square wave ranging formula, eliminating the influence of transfer function parameter mismatch or circuit offset, etc.

[0084] Figure 7 Illustrates the implementation method steps of the present invention. S101 The controller 120 controls the light source 110 to emit light, which can be a square wave, a triangular wave, a sine wave, etc., and is not specifically limited here. Under the action of the emitted light, the field of view is illuminated, and the object to be detected 150 reflects the emitted light, thus forming a reflected light echo. S102 While the controller 120 controls the light source to emit light, it controls the receiving unit 130 to receive the echo of the reflected light with a control signal having a different phase delay from the light source 110. S103 The receiving unit 130 respectively obtains electrical signals corresponding to at least one phase control signal among multiple same-phase or different-phase received signals through two circuits, where multiple same-phase or different-phase received signals refer to multiple delay control signals of the same phase and different phases. For example, the number of four delay phases is four. S104 The information acquisition unit 140 obtains the target information of the object to be detected 150 based on the electrical signals corresponding to at least one same-phase control signal respectively obtained by the two circuits. The electrical signals corresponding to at least one same-phase control signal can be used in the middle or final calculation of target information acquisition. The schemes of using this electrical signal in physical or digital ways have been described before and will not be elaborated here.

[0085] Figure 8 Illustrates another implementation method step of the present invention, and Figure 7The steps shown are similar. In Figure 8 further defines a solution for obtaining target information using a four-phase scheme. The implementation of the corresponding steps can refer to Figure 7 the steps described. Details will not be elaborated here again.

[0086] Figure 9 Schematically shows another implementation step of the present invention, which is similar to the steps shown in Figure 7 and Figure 8 In Figure 9 further defines a solution for obtaining target information using a four-phase scheme, and defines that each of the four delay phases obtains corresponding electrical signals through two circuits. The implementation of the corresponding steps can refer to Figure 7 the steps described. Details will not be elaborated here again.

[0087] It should be noted that in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0088] 1. The above are only preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. The above are only preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A detection device, characterized in that Including: A light source operable to emit light for illuminating an object to be detected; A receiving part having a photoelectric conversion module, the receiving part being configured to obtain the amount of light of the light source reflected by the object to be detected, and the photoelectric conversion module being capable of generating corresponding photo-generated electrons according to the received amount of light; the receiving part further includes a first circuit and a second circuit for converting incident light into respective electrical signals, wherein the first circuit is configured to receive a first modulation signal, the second circuit is configured to receive a second modulation signal, and wherein the first circuit and the second circuit are configured to generate respective electrical signals according to the first modulation signal and the second modulation signal; a controller electrically connectable to the light source to emit light for illuminating the object to be detected, and at the same time the controller is also electrically connectable to the receiving part, the receiving part can receive a plurality of reception control signals in phase or out of phase with the light emission signal of the light source, and obtain electrical signals corresponding to at least one reception control signal with the same phase through the two circuits; an information acquisition unit capable of obtaining a target correction coefficient of the object to be detected according to the electrical signals of the reception control signals with the same phase respectively obtained by the two circuits, and obtaining target information of the object to be detected based on the target correction coefficient; f(0°) = mf(0°_1) + nf(0°_2); f(0°) refers to the final information result corresponding to the phase to be corrected, f(0°_1) refers to the information result corresponding to the phase obtained by the first circuit, f(0°_2) refers to the information result corresponding to the phase obtained by the second circuit, where m and n are correction coefficients taking values in the interval [-1, 1].

2. The detection device according to claim 1, characterized in that, The plurality of reception control signals in phase or out of phase with the light emission signal of the light source are four reception control signals with different phases.

3. The detection device according to claim 1, characterized in that, During the operation of obtaining the target information, the electrical signals corresponding to the reception control signals with the same phase are at least subjected to a summation process.

4. The detection device according to claim 1, characterized in that The plurality of reception control signals in phase or out of phase include four phase signals of 0°, 90°, 180° and 270°, and the receiving part obtains electrical signals corresponding to the reflected light with the same phase through the two circuits for at least one of the reception control signals of the phases.

5. The detection device according to claim 1, wherein The two circuits respectively obtain different electrical signals corresponding to each phase of the plurality of reception control signals in phase or out of phase.

6. The detection device according to claim 1, wherein, The first modulation signal is inverse to the second modulation signal in at least part of the time period.

7. The detection device according to claim 1, characterized in that, The light source at least includes four emissions of light with the same duration, and the circuit modulation signals corresponding to two reception control signals with a phase difference of 180° are inverse signals.

8. The detection device according to claim 7, characterized in that, There is a first time interval between the circuit modulation signals corresponding to two reception control signals with a phase difference of 90°, and both are converted into different electrical signals by the first circuit and the second circuit in the receiving part that receive the first modulation signal and the second modulation signal.

9. The detection device according to claim 1, characterized in that, The first circuit and the second circuit are connected to the same pixel unit, receive the first modulation signal and the second modulation signal, and generate respective electrical signals.

10. The detection device according to claim 9, characterized in that, The receiving part includes a plurality of the pixel units arranged in an array.

11. A detection method, characterized in that, Applied to the detection device described in any one of the above claims 1-10, the detection method includes: the receiving part obtains the light quantity of the light source reflected by the object to be detected under the control of a control signal, and the photoelectric conversion module in the receiving part can generate corresponding photo-generated electrons according to the received light quantity; the receiving part further includes a first circuit and a second circuit for converting incident light into respective electrical signals, wherein the first circuit is configured to receive the control of a first modulation signal, and the second circuit is configured to receive the control of a second modulation signal, and wherein the first circuit and the second circuit are configured to generate respective electrical signals according to the first modulation signal and the second modulation signal; a controller controls the light source to emit light to illuminate the object to be detected, and at the same time the controller can also control the receiving part, and the receiving part can receive multiple receiving control signals that are in phase or out of phase with the light signal emitted by the light source, and obtain electrical signals corresponding to at least one in-phase receiving control signal through the two circuits respectively; an information acquisition unit can obtain the target correction coefficient of the object to be detected according to the electrical signals of the in-phase receiving control signals respectively obtained by the two circuits, and obtain the target information of the object to be detected based on the target correction coefficient; f(0°) = mf(0°_1) + nf(0°_2); f(0°) refers to the final information result corresponding to the phase to be corrected, f(0°_1) refers to the information result corresponding to the phase obtained by the first circuit, f(0°_2) refers to the information result corresponding to the phase obtained by the second circuit, where m and n are correction coefficients taking values in the interval [-1, 1].

12. The detection method according to claim 11, characterized in that, The multiple receiving control signals that are in phase or out of phase with the light signal emitted by the light source are four receiving control signals with different phases.

13. The detection method according to claim 11, wherein, During the operation process of obtaining the target information, the electrical signals corresponding to the in-phase receiving control signals are at least subjected to a summation process.

14. The detection method according to claim 11, characterized in that The multiple receiving control signals that are in phase or out of phase include four phase signals of 0°, 90°, 180°, and 270°, and the receiving part obtains electrical signals corresponding to the same-phase reflected light through the two circuits respectively for at least one of the phase receiving control signals.

15. The detection method according to claim 11, wherein The two circuits respectively obtain different electrical signals corresponding to each phase of the multiple receiving control signals that are in phase or out of phase.

16. The detection method according to claim 15, characterized in that, The first modulation signal is inverse to the second modulation signal in at least part of the time period.

17. The detection method according to claim 11, characterized in that The light source at least includes four emissions of light with the same duration, and the circuit modulation signals corresponding to two receiving control signals with a phase difference of 180° are inverse signals.

18. The detection method according to claim 17, wherein There is a first time interval between the circuit modulation signals corresponding to two receiving control signals with a phase difference of 90°, and both are converted into different electrical signals by the first circuit and the second circuit in the receiving part that receive the first modulation signal and the second modulation signal.

19. The detection method according to claim 11, characterized in that, The first circuit and the second circuit are connected to the same pixel unit, receive the first modulation signal and the second modulation signal, and generate respective electrical signals.

20. The detection method according to claim 19, wherein, The receiving part includes a plurality of pixel units arranged in an array.

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