CN220570632U

CN220570632U - Photoelectric sensor, pixel unit thereof, pulse camera and electronic equipment

Info

Publication number: CN220570632U
Application number: CN202321879126.1U
Authority: CN
Inventors: 韩润泽
Original assignee: Pulse Vision Beijing Technology Co ltd
Current assignee: Pulse Vision Beijing Technology Co ltd
Priority date: 2023-07-17
Filing date: 2023-07-17
Publication date: 2024-03-08
Anticipated expiration: 2033-07-17

Abstract

The embodiment of the disclosure discloses a photoelectric sensor, a pixel unit thereof, a pulse camera and electronic equipment, wherein the pixel unit comprises a pulse generating circuit, a pulse width counter, a first comparator and a pulse number counter; the pulse generating circuit is respectively connected with the pulse width counter and the first comparator; the pulse width counter is connected with the first comparator; the first comparator is connected with the pulse number counter, so that the data volume of the coded data can be reduced, the data volume of externally transmitted data is reduced, the transmission pressure is reduced, and the transmission efficiency is improved.

Description

Photoelectric sensor, pixel unit thereof, pulse camera and electronic equipment

Technical Field

The present disclosure relates to information processing technology, codec technology, and more particularly to a photoelectric sensor, a pixel unit thereof, a pulse camera, and an electronic device.

Background

The pulse camera collects and accumulates the light signals of the observation scene through the built-in photoelectric sensor, and when the accumulated quantity of the light signals exceeds a preset threshold value, a pulse signal is generated and issued to form a pulse sequence, so that high-precision expression and continuous recording of a high-speed light process are realized.

However, since the pulse sequence requires a very large amount of data for high-precision expression and continuous recording of a high-speed optical process, there is a great pressure in terms of transmission bandwidth, transmission instantaneity, and the like. Therefore, how to reduce the transmission pressure and improve the transmission efficiency is a technical problem to be solved.

Disclosure of Invention

The embodiment of the disclosure provides a photoelectric sensor, a pixel unit thereof, a pulse camera and electronic equipment, so as to at least partially solve the technical problems.

In one aspect of the embodiments of the present disclosure, there is provided a pixel unit of a photosensor, including: a pulse generating circuit, a pulse width counter, a first comparator and a pulse number counter;

the pulse generating circuit is respectively connected with the pulse width counter and the first comparator;

the pulse width counter is connected with the first comparator;

the first comparator is connected with the pulse number counter.

Optionally, in the pixel unit of any one of the embodiments of the disclosure, further includes: a pulse width memory;

the pulse width memory is respectively connected with the pulse width counter and the first comparator.

Optionally, in the pixel unit of any embodiment of the disclosure, the pulse generating circuit includes: a photodiode, a reset transistor, and a second comparator;

The anode of the photodiode is grounded, and the cathode of the photodiode is respectively connected with the source electrode of the reset transistor and the negative input end of the second comparator;

the source electrode of the reset transistor is connected with the cathode of the photodiode, the drain electrode of the reset transistor is connected with the power supply module, and the grid electrode of the reset transistor is connected with the output end of the second comparator;

the positive input end of the second comparator is connected with an external reference signal, the negative input end of the second comparator is connected with the negative electrode of the photodiode, and the output end of the second comparator is respectively connected with the grid electrode of the reset transistor and the pulse width counter.

Optionally, in the pixel unit of any one of the embodiments of the disclosure, further includes: a clock circuit;

the clock circuit is respectively connected with the pulse width counter and the first comparator.

Optionally, in the pixel unit of any one of the embodiments of the disclosure, further includes: a scanning circuit;

the scanning circuit is respectively connected with the pulse generating circuit and the first comparator.

Optionally, in the pixel unit of any one of the embodiments of the disclosure, further includes: an encoder;

The encoder is respectively connected with the pulse number counter and the clock circuit.

In another aspect of the embodiments of the present disclosure, there is provided a photoelectric sensor including: a plurality of pixel units according to any of the embodiments of the present disclosure.

In another aspect of embodiments of the present disclosure, a pulse camera is provided, including a photosensor according to any of the embodiments of the present disclosure.

In another aspect of an embodiment of the present disclosure, there is provided an electronic device including:

the processor may be configured to perform the steps of,

a memory communicatively coupled to the processor;

a pixel cell as described in any embodiment of the present disclosure or a photosensor as described in any embodiment of the present disclosure connected to the processor.

Optionally, in an electronic device of any embodiment of the disclosure, the electronic device is incorporated as any one of: pulse cameras, high-speed cameras, audio/video players, navigation devices, fixed location terminals, entertainment units, smartphones, communication devices, devices in motor vehicles, cameras, motion or wearable cameras, detection devices, flight devices, medical devices, security devices.

According to the embodiment of the disclosure, the pixel unit comprises a pulse generating circuit, a pulse width counter, a first comparator and a pulse number counter, wherein the pulse generating circuit is respectively connected with the pulse width counter and the first comparator, the pulse width counter is connected with the first comparator, the first comparator is connected with the pulse number counter, a photon stream received in space can be converted into a pulse sequence (comprising a plurality of pulse signals arranged according to a time sequence relation) representing a light intensity change process through the pulse generating circuit, pulse width of each pulse signal in the pulse sequence is counted through the pulse width counter, whether the pulse width of each pulse signal is changed or not is compared through the first comparator, the pulse number counter counts the pulse number with unchanged pulse width, and when the pulse width of each pulse signal is changed, a pulse number count value is output outwards so as to encode the pulse signal number and time information of each pulse signal with changed, and the pulse signal with unchanged pulse width is not required to be encoded, so that the data quantity of encoded data can be reduced, the data quantity of the data transmitted can be reduced, the data transmission pressure of the data can be reduced, and the transmission efficiency can be improved; secondly, as the data volume of the coded data is reduced, the hardware resources occupied by the coded data can be saved, so that the hardware requirements are reduced, and the coding efficiency and the resource utilization rate are improved; in addition, when pulse width is directly encoded, the limitation of the imaging dynamic range due to the limitation of the recordable pulse width range caused by hardware limiting factors such as hardware area, power consumption and the like can be avoided, and the imaging dynamic range can be improved under the condition of reducing the data quantity of encoded data.

The technical scheme of the present disclosure is described in further detail below through the accompanying drawings and examples.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure.

The disclosure may be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings in which:

fig. 1 is a schematic structural diagram of an embodiment of a pixel unit of a photosensor according to the present disclosure.

Fig. 2 is a schematic structural diagram of another embodiment of a pixel unit of the photoelectric sensor of the present disclosure.

Fig. 3 is a schematic structural diagram of a pixel unit of a photosensor according to another embodiment of the present disclosure.

Fig. 4 is a diagram illustrating an example of information related to a pulse signal according to an embodiment of the present disclosure.

Fig. 5 is a related information example of another pulse signal in the embodiment of the present disclosure.

Fig. 6 is a related information example of still another pulse signal in the embodiment of the present disclosure.

Fig. 7 is a schematic structural diagram of an application embodiment of the electronic device of the present disclosure.

Detailed Description

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components set forth in these embodiments does not limit the scope of the present disclosure unless specifically stated otherwise.

It will be appreciated by those of skill in the art that the terms "first," "second," etc. in embodiments of the present disclosure are used merely to distinguish between different steps, devices or modules, etc., and do not represent any particular technical meaning nor necessarily logical order between them.

It should also be understood that in embodiments of the present disclosure, "plurality" may refer to two or more, and "at least one" may refer to one, two or more.

It should also be appreciated that any component, data, or structure referred to in the presently disclosed embodiments may be generally understood as one or more without explicit limitation or the contrary in the context.

In addition, the term "and/or" in this disclosure is merely an association relationship describing an association object, and indicates that three relationships may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" in the present disclosure generally indicates that the front and rear association objects are an or relationship.

It should also be understood that the description of the various embodiments of the present disclosure emphasizes the differences between the various embodiments, and that the same or similar features may be referred to each other, and for brevity, will not be described in detail.

Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses.

Techniques, equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

Embodiments of the present disclosure may be applicable to cameras (e.g., pulse cameras), terminal devices, computer systems, servers, and the like, which may operate with numerous other general purpose or special purpose computing system environments or configurations. Examples of well known terminal devices, computing systems, environments, and/or configurations that may be suitable for use with cameras, terminal devices, computer systems, servers, and the like include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, hand-held or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network personal computers, small computer systems, mainframe computer systems, and distributed cloud computing technology environments that include any of the foregoing, and the like.

Fig. 1 is a schematic structural diagram of an embodiment of a pixel unit of a photosensor according to the present disclosure. As shown in fig. 1, the pixel unit of the photosensor of this embodiment includes: a pulse generation circuit 102, a pulse width counter 104, a first comparator 106, and a pulse number counter 108. Wherein:

the pulse generating circuit 102 is connected to the pulse width counter 104 and the first comparator 106, respectively.

The pulse width counter 104 is connected to the first comparator 106.

The first comparator 106 is connected to a pulse number counter 108.

Each pulse generating circuit 102 may be used as a photosensitive unit, continuously collect a spatial optical signal and convert the optical signal into an electrical signal for accumulation, so as to obtain a signal accumulation amount, generate a pulse signal every time the signal accumulation amount reaches a preset accumulation threshold value, set the signal accumulation amount to 0 for accumulation again, and trigger the first comparator 106 to compare the pulse width count value with a specified pulse width. A pulse width counter 104 for accumulating and counting pulse widths of the pulse signals under the control of the external clock circuit during each pulse signal period (i.e., signal accumulation amount is accumulated from zero to a preset accumulation threshold value) of the pulse generation circuit 102; after the pulse generating circuit 102 generates one pulse signal, the count is stopped, and the pulse width count value is output to the first comparator 106. A first comparator 106 that compares whether the pulse width count value output from the pulse width counter 104 is the same as the specified pulse width value or not under the triggering of the pulse generating circuit 102, and sets the pulse width count value of the pulse width counter 104 to 0 so as to restart counting from 0; if the comparison result is the same, indicating that the pulse width of the pulse signal is not changed, adding 1 to the pulse number count value of the trigger pulse number counter 108, and continuing to count the number of pulse signals with the same pulse width in an accumulating way; if the comparison results are different, it indicates that the pulse width of the pulse signal is changed, the trigger pulse number counter 108 outputs a pulse number count value, and at the same time, triggers the external clock circuit to output timing information (time information) so as to encode and output the pulse number and time information with the changed pulse width. In a specific implementation, the first comparator 106 may output 0 when the comparison result is the same, output 1 when the comparison result is different, or vice versa, according to the comparison logic, which is not limited by the embodiments of the present disclosure. The time information of the clock circuit may be a pulse start time of the pulse signal or a pulse end time of the pulse signal, which is not limited in the embodiment of the present disclosure. The pulse number count value and the timing information can be output to the external buffer block through an asynchronous communication protocol.

Based on the embodiment, as only the pulse signal quantity and the time information of the pulse signals with the pulse widths being changed are encoded and the pulse signals with the pulse widths not being changed are not required to be encoded, the data quantity of encoded data can be reduced, the data quantity of externally transmitted data is reduced, the transmission pressure is reduced, and the transmission efficiency is improved; in addition, the data volume of the coded data is reduced, so that the hardware resources occupied by the coded data can be saved, the hardware requirements are reduced, and the coding efficiency and the resource utilization rate are improved.

Fig. 2 is a schematic structural diagram of another embodiment of a pixel unit of the photoelectric sensor of the present disclosure. As shown in fig. 2, on the basis of the embodiment shown in fig. 1, the pixel unit of this embodiment may further include: a pulse width memory 110, the pulse width memory 110 being connected to the pulse width counter 104 and the first comparator 106, respectively.

The pulse width memory 110 stores a specified pulse width value. The first comparator 106 enables updating the value in the pulse width memory 110 (i.e., the designated pulse width) to the pulse width count value output by the pulse width counter 104 when the comparison results are different.

Based on the embodiment, the designated pulse width value in the pulse width memory 110 is updated to the pulse width count value output by the pulse width counter 104, so that dynamic update of the designated pulse width can be realized, and whether the pulse width of the next pulse signal changes can be confirmed based on the designated pulse width, thereby realizing effective determination of whether the pulse width of each pulse signal in the pulse sequence changes.

Optionally, referring again to fig. 2, in some of these implementations, the pulse generation circuit 102 may include: a Photodiode (PD) 1022, a reset transistor 1024, and a second comparator 1026. Wherein the anode of the photodiode 1022 is grounded, and the cathode is connected to the source of the reset transistor 1024 and the negative input terminal of the second comparator 1026, respectively, and is used for outputting a current signal. The reset transistor 1024 has a source connected to the cathode of the photodiode 1022, a drain connected to the power supply module (voltage Vdd), and a gate connected to the output terminal of the second comparator 1026. The positive input end of the second comparator 1026 is connected to the external reference signal Vref, the negative input end is connected to the negative electrode of the photodiode 1022, and the output end is connected to the gate of the reset transistor 1024, the pulse width counter 104 and the first comparator 106, respectively.

The photodiode 1022 starts collecting the light signal when the light signal arrives and converts it into a current signal, the voltage Vpd on the photodiode 1022 starts to drop cumulatively under the action of the current, and is reset when the voltage Vpd drops to the reference signal Vref (as a preset accumulation threshold). A photodiode is a photodetector capable of converting an optical signal into a current or voltage signal. The die often uses a PN junction with photosensitive characteristics, is very sensitive to light changes, has unidirectional conductivity, and changes electrical characteristics when different light intensities are used, so that the intensity of the light can be used to change the voltage or current in the circuit. The second comparator 1026 compares the reference signal Vref with the voltage Vpd on the photodiode 1022 under the control of the clock circuit, outputs a low level 0 to the pulse width counter 104 when the voltage Vpd is greater than the reference signal Vref, generates a pulse signal and issues when the voltage Vpd is less than or equal to the reference signal Vref, and outputs a high level 1 to the reset transistor 1024 and the first comparator 106, respectively, to control the reset transistor 1024 to reset the voltage Vpd, and triggers the first comparator 106 to compare whether the pulse width count value output by the pulse width counter 104 is the same as the specified pulse width value.

Specifically, the comparison of the reference signal Vref and the voltage Vpd may be implemented by the second comparator 1026, and when the reference signal Vref is less than or equal to the voltage Vpd, the output terminal outputs low level 0 to the pulse width counter 104; when the reference signal Vref is greater than the voltage Vpd, the output terminal outputs a high level 1 to the reset transistor 1024 and the first comparator 106, respectively. Alternatively, the reference signal Vref may be a voltage signal less than the power module voltage Vdd.

Fig. 3 is a schematic structural diagram of a pixel unit of a photosensor according to another embodiment of the present disclosure. As shown in fig. 3, in the pixel unit according to any embodiment of the present disclosure, the method may further include: the clock circuit 202, the clock circuit 202 is connected to the pulse width counter 104 and the first comparator 106, respectively. The clock circuit 202 counts time in a unit period, and can output timing information (time information) to the outside in response to the triggering of the first comparator 106.

It should be noted that in the embodiment of the present disclosure, a synchronous clock circuit 202 may be respectively disposed in each pixel unit of the photoelectric sensor, and provide a clock signal for the pixel unit. In addition, a clock circuit 202 may be provided in the photosensor to supply clock signals to the pixel units of the photosensor, respectively. Alternatively, a clock circuit 202 may be disposed in each row of pixel units, each column of pixel units, each row of pixel units, or each column of pixel units of the photosensor, and each clock circuit 202 may provide a clock signal to each row of pixel units or each column of pixel units. The embodiments of the present disclosure are not limited in this regard. The present embodiment only exemplifies the connection relation of the clock circuit 202 and other circuit elements in the pixel unit, and does not indicate that it must be provided in the pixel unit.

In the embodiment of the disclosure, the photoelectric sensor may include a plurality of rows and a plurality of columns of pixel units, each pixel unit is arranged to form a pixel unit array, each pixel unit in the pixel unit array respectively performs time domain sampling on an optical signal in a designated space in the whole observation scene, spaces corresponding to different pixel units in the pixel unit array are not overlapped, and each pixel unit in the pixel unit array is mutually matched to cover the whole observation scene, so that the sampling on the optical signal in the whole observation scene can be realized. Based on the generation time of the pulse signals corresponding to each space, the pulse signals corresponding to each space are arranged according to a time sequence relationship, so that a pulse sequence for expressing the light intensity and the change process of the light intensity of the space can be obtained.

Optionally, referring back to fig. 3, in the pixel unit of any one embodiment of the disclosure, the method may further include: a scanning circuit 204, the scanning circuit 204 being connected to the pulse generating circuit 102 and the first comparator 106, respectively.

The scanning circuit 204 scans the position (x, y) of the pulse generating circuit 102 or the pixel unit thereof in the pixel unit array photosensor, which may also be referred to as the position in the photosensor, where x and y respectively represent the position of the pulse generating circuit 102 or the pixel unit in the x-th row and the y-th column in the pixel unit array. When the comparison results are different, the first comparator 106 may trigger the scan circuit 204 to scan the position (x, y) of the pulse generating circuit 102 or the pixel unit thereof in the pixel unit array and output the scanned position to the external buffer block.

It should be noted that in the embodiment of the present disclosure, a scanning circuit 204 may be respectively disposed in each pixel unit of the photoelectric sensor, and the scanning circuit 204 scans the position of the pixel unit in the pixel unit array when the pulse width of the pulse signal changes according to the triggering of the first comparator 106. In addition, a scanning circuit 204 may be provided for the entire photosensor to scan the positions of the pixel units emitting pulse signals in the photosensor in the pixel unit array. Alternatively, one scanning circuit 204 may be provided for each row pixel unit, each column pixel unit, or each row pixel unit, or each column pixel unit of the photosensor, and each scanning circuit 204 may scan the position of each pixel unit, which emits a pulse signal, in the pixel unit array, among the pixel units connected thereto. The embodiments of the present disclosure are not limited in this regard. The present embodiment only exemplifies the connection relation of the scanning circuit 204 with other circuit elements in the pixel unit, and does not indicate that it must be provided in the pixel unit.

Optionally, referring back to fig. 3, in the pixel unit of any one embodiment of the disclosure, the method may further include: an encoder 206, the encoder 206 being connected to the pulse number counter 108 and the clock circuit 202, respectively.

The encoder 206 encodes the pulse count value output from the pulse count counter 108 and the time information output from the clock circuit 202, or further encodes the position (x, y) of the pixel unit in the photosensor in combination with the position output from the scanning circuit 204, to obtain encoded information corresponding to each pulse signal. Alternatively, the pulse number counter 108, the clock circuit 202 and the scan circuit 204 may correspondingly output the pulse number count value, the time information and the position (x, y) to the external buffer block, and the encoder 206 may also be connected to the external buffer block, and encode the pulse number count value and the time information stored in the external buffer block, or further combine the position (x, y) to obtain the encoded information corresponding to each pulse signal. The format of the encoded data may be set according to actual requirements, for example, in an implementation example, the format of the encoded data may be expressed as (x, y, t, C), where x and y respectively represent positions of the pixel units in the x-th row and the y-th column in the pixel unit array, t represents time information, and C represents the pulse number count value. The disclosed embodiments do not limit the encoded data format. After the coding information corresponding to each pulse signal is obtained, the coding information of the pulse signals corresponding to the space can be arranged to form a coding sequence based on a time sequence relation.

In the embodiment of the present disclosure, one encoder 206 may be provided for each pixel unit of the photosensor, one encoder 206 may be provided for the entire photosensor, or one encoder 206 may be provided for each row pixel unit, each column pixel unit, or each row pixel unit, or each column pixel unit of the photosensor, respectively, to encode the number of pulse signals output by the pulse number counter 108, the time information output by the clock circuit 202, and the position (x, y) output by the scanning circuit 204. The embodiments of the present disclosure are not limited in this regard. The present embodiment only exemplarily shows the connection relation of the encoder 206 and other circuit elements in the pixel unit, and does not indicate that it must be disposed in the pixel unit.

For ease of reference, in the embodiments of the present disclosure, a pulse signal whose pulse width is changed is referred to as a target pulse signal.

Alternatively, in some implementations, the pulse start time of the target pulse signal output by the clock circuit may be used as time information to be encoded, and the pulse number count value obtained by counting the number of pulse signals of the same pulse width adjacent to the target pulse signal by the pulse number counter may be used as the number of pulse signals to be encoded.

Fig. 4 is a diagram illustrating an example of information related to a pulse signal according to an embodiment of the present disclosure. As shown in fig. 4, the intensities of the photocurrents of the sections, that is, the optical signal intensities (that is, the light intensities) or the converted electric signal intensities (that is, the current intensities), are marked, and the preset accumulation threshold of the photocurrent intensities is set to 20, so that for the light intensity of the photocurrent intensity of 4, after 5 unit periods, the preset accumulation threshold is reached, and a pulse is triggered and generated. For the change of the photocurrent intensity from 4 to 5, it is assumed here that the photocurrent intensity is 4 for 16 unit periods, since the generation of a pulse is triggered at the 15 th unit period and then the light intensity of the photocurrent intensity of 4 for one unit period is continued, and when the light intensity of 5 is reached, the preset accumulation threshold is reached and the generation of a pulse is triggered through (20-4)/5=3.2 unit periods, so that the generation of a pulse is triggered again at the end of the 19.2 th unit period, and the pulse interval (i.e., pulse width) is 4.2.

Taking fig. 4 as an example, in this implementation, since the pulse widths of the pulses generated at the end time of the 5 th, 10 th, and 15 th unit periods are the same and are 5, and the pulse width of the pulse generated at the end time of the 19.2 th unit period is 4.2, the pulse signal generated at the end time of the 19.2 th unit period is the target pulse signal when the pulse width of the preceding three pulses is changed, and encoding is necessary. The encoded time information is the pulse start time (i.e., the pulse end time of the previous adjacent pulse signal) 15 of the target pulse signal, and the encoded pulse signal number (i.e., the pulse number count value output by the pulse number counter 108) is 3 of the adjacent pulse signals with the same pulse width before the target pulse signal, and the time information 15 and the number 3 of pulse signals are encoded. Based on each two pieces of adjacent encoded information, a period in which the encoded information is to be the next (a period between the time information in the encoded information and the time information in the encoded information is hereinafter referred to as an encoded period) and the number of pulses in the encoded period, in which the pulse width is the same, can be determined, and by the ratio of the encoded period and the number of pulses, the pulse width of each pulse signal in each period of the observation scene can be determined.

Alternatively, in other implementations, the time information to be encoded may be the pulse start time of the pulse signal of the same pulse width adjacent to the target pulse signal output by the clock circuit, and the pulse number count value obtained by counting the number of the pulse signals of the same pulse width by the pulse number counter may be the number of the pulse signals to be encoded.

Fig. 5 is a related information example of another pulse signal in the embodiment of the present disclosure. As shown in fig. 5, the pulse width of the pulse generated at the end time of the 32.5 th unit cycle is 4.4, the pulse widths of the pulses generated at the end times of the 42.5 th, 52.5 th and 62.5 th unit cycles are 10, the pulse width of the pulse generated at the end time of the 77 th unit cycle is 14.5, and the pulse width of the pulse is changed from the pulse width of the pulse adjacent to the pulse generated at the end time of the 77 th unit cycle, and the pulse signal is encoded as the target pulse signal. The encoded time information is the pulse start time 32.5 of the pulse signal of the same pulse width adjacent to the target pulse signal, and the encoded pulse signal number (i.e., the pulse number count value output by the pulse number counter 108) is 3, and the time information 32.5 and the pulse signal number 3 are encoded. Based on each two adjacent encoded information, the encoding time period corresponding to the previous encoded information (including the time between the time information in the previous encoded information and the time information in the next encoded information) and the number of pulses with the same pulse width in the encoding time period can be determined, and the pulse width of each pulse signal in each time period of the observation scene can be determined by the ratio of the encoding time period and the number of pulses.

Alternatively, in still other implementations, the pulse end time of the target pulse signal output by the clock circuit may be used as the time information to be encoded, and the number of pulse signals between the pulse end time of the previous target pulse signal adjacent to the target pulse signal and the pulse end time of the target pulse signal may be counted by the pulse number counter to be used as the number of pulse signals to be encoded.

Fig. 6 is a related information example of still another pulse signal in the embodiment of the present disclosure. As shown in fig. 6, the pulse width of the pulse generated at the end time of the 32.5 th unit period is 4.4, the pulse widths of the pulses generated at the end time of the 42.5 th unit period are 10, and the pulse widths of the pulses adjacent to each other are changed as the target pulse signal; the pulse widths of the pulses generated at the end time of the 52.5 th and 62.5 th unit periods are 10, and the pulse widths of the pulses adjacent to the pulse width of the pulse are unchanged from the pulse widths of the pulses adjacent to the pulse width of the pulse width generator, and the pulse width generator is not used as a target pulse signal; the pulse width of the pulse generated at the end of the 77 th unit period is 14.5, and the pulse width of the pulse is changed from the pulse width of the pulse adjacent to the pulse, and encoding is required as the target pulse signal. In the present embodiment, the pulse generated at the end of the 77 th unit cycle is taken as the target pulse signal, and the encoding period is (42.5,77) ]The pulse end time 77 of the target pulse signal is used as time information to be encoded, and the encoding time period is (42.5,77)]The number of internally generated pulse signals is 3, and the time information 77 and the number of pulse signals 3 are encoded. The pulse width of a target pulse signal generated by time information in the latter encoded information can be determined based on every two adjacent encoded information, and the number and pulse width of other pulse signals in the encoding time period can be determined based on the pulse width of the target pulse signal, the same number of pulses as the pulse width in the encoding time period, and the pulse width in the former encoded information, thereby determining the pulse width of each pulse signal in each time period of the observation scene. For example, the time information t in the latter encoded information i can be determined as follows _i Pulse width τ of target pulse signal generated _i ：t _i -t _i-1 -(C _i-1 )τ _i-1 Wherein i is the code signal in the same code sequenceThe value of i is an integer greater than 1, t represents time information, and C represents pulse signal information.

The actual pulse width of the pulse signal, that is, the accumulated duration of the pulses of the pulse signal, is the time interval between the pulse signal and the pulses of the adjacent previous pulse signal, and may be the actual pulse width of the current pulse signal by the time interval between the pulse end time of the current pulse signal and the pulse start time (that is, the pulse end time of the adjacent previous pulse signal).

In practical applications, the range of pulse widths that can be recorded by the pulse width counter 104 is limited due to hardware limitations such as hardware area and power consumption. In some implementations, the maximum pulse width of the pulse width counter 104 is used as a preset recording pulse width, when the pulse width count value does not reach the preset recording pulse width, the actual pulse width of the pulse signal is directly recorded, when the pulse width count value exceeds the preset recording pulse width, the pulse width count value is set to 0, and counting is performed again from 0, so that effective recording of the actual pulse width of the pulse signal is realized, and whether the pulse width of the pulse signal changes or not is conveniently confirmed.

For example, limited by the hardware area, power consumption, etc., the pulse width that can be recorded by the pulse width counter 104 is from 0 to 7, and then the preset recording pulse width is 7. If the actual pulse width of a pulse signal is greater than the preset recorded pulse width, according to the present embodiment, the pulse width of the pulse signal recorded by the pulse width counter 104 corresponds to the remainder of the division between the actual pulse width of the pulse signal and the preset recorded pulse width, for example, assuming that the actual pulse width of the current pulse signal is 10 and exceeds the preset recorded pulse width 7, the pulse width count value is set to 0 and the counting is restarted after the pulse width count value exceeds the preset recorded pulse width, and the recorded pulse width of the pulse signal is 3, i.e. 10%7=3. If the actual pulse width of the current pulse signal is not greater than the preset recording pulse width, the recorded pulse width of the pulse signal is the actual pulse width of the pulse signal, for example, assuming that the actual pulse width of the pulse signal is 6, the recorded pulse width of the current pulse signal is 6.

In combination with the example and the encoding method shown in fig. 6, since the preset recording pulse width is 7, for the pulse from the end time of the 32.5 th unit period to the end time of the 42.5 th unit period (denoted as (32.5,42.5)), the width thereof is 10, exceeding the preset recording pulse width, the pulse width of the recorded pulse signal is 3, the previous pulse width thereof is 32.5-28.1=4.4, since 3 and 4.4 are not equal, the pulse generated at the end time of the 42.5 th unit period is regarded as the target pulse signal, encoding is performed to output encoding information, the number of pulse signals generated in the encoding period (32.5,42.5) is counted as 1 by the pulse number counter 108, the encoding data is (42.5,1), the designated pulse width is updated to 3, and the number of pulse signals is set to 0 by the pulse number counter 108; the pulse width of the pulse in the encoding period (42.5,52.5) is 3, the pulse width is equal to the previous pulse width 3, the pulse number count value of the pulse number counter 108 is added with 1 as the target pulse signal, the pulse width of the pulse in the encoding period (42.5,52.5) is 3, the pulse number count value of the pulse number counter 108 is added with 1 as the target pulse signal, the pulse width of the pulse in the encoding period (62.5,77) is 14.5%7=0.5, the pulse width of the pulse in the encoding period (62.5,77) is not equal to the previous pulse width 3, the pulse number count value 1 of the pulse number counter 108 is used as the target pulse signal, encoding is performed to output encoding information, the encoding data is (77,3), and then the pulse number count value of the pulse number counter 108 is set to 0.

The range of pulse widths that can be recorded by the pulse width counter is limited due to hardware limitations such as hardware area, power consumption, and the like. Based on the embodiment, the maximum pulse width recorded by the hardware support of the pulse width counter is used as a preset recording pulse width, the actual pulse width of the pulse signal is directly recorded when the pulse width count value does not reach the preset recording pulse width, the pulse width count value is set to 0 again for counting after the pulse width count value exceeds the preset recording pulse width, the effective recording of the actual pulse width of the pulse signal is realized, the corresponding pulse width can be determined through encoding the pulse signal quantity and time information of the pulse signal with each pulse width changed, the limitation of the imaging dynamic range due to the limitation of the recorded pulse width range caused by hardware area, power consumption and other hardware limiting factors can be avoided, and the imaging dynamic range can be improved under the condition of reducing the data quantity of encoded data.

In practical applications, when the actual pulse width difference between two adjacent pulse signals is exactly the preset recorded pulse width, the pulse widths of the two pulse signals determined based on the embodiments of the present disclosure are the same, which may generate errors. In most practical scenes, the light intensity variation of a single space is not particularly intense, and the light intensity variation is a very small probability event and does not influence the overall effect. In an alternative implementation, the preset recording pulse width can be reasonably set for the actual scene, so as to effectively avoid the occurrence of the situation. For example, the preset recording pulse width may be set to a pulse width corresponding to the maximum light intensity of the area in the actual scene or a pulse width corresponding to the average light intensity of the area, which is not limited by the specific setting factor and the value of the preset recording pulse width in the embodiment of the present disclosure.

Optionally, in any embodiment of the present disclosure, after obtaining the coding information corresponding to each pulse signal, the coding sequence of the pixel unit may be obtained by sorting the coding information corresponding to each pulse signal based on the timing relationship of the pulse signals corresponding to the same pixel unit. Further, a code sequence array may also be formed from the code sequences corresponding to the respective pixel units based on the positions of the respective pixel units in the pixel unit array, and then the code sequence array may be output using an asynchronous communication protocol, for example, address event expression (Address Event Representation, AER).

An image at any time can be reconstructed based on the array of code sequences. When the coding sequence array is output by adopting an asynchronous transmission protocol mode, as each pixel unit is allocated with an address, the event is transmitted through a high-speed digital parallel bus corresponding to the position of the pixel unit in the pixel unit array (or image). When the pixel unit generates a coded message, a digital address is assigned to the coded message, which is routed over the bus to the target chip, and by analyzing the digital address, the pixel unit is able to send an event to any target neuron in the target chip. In this way, the pixel cells and cells/modules with the same address in the target chip are actually connected to the same impulse, and the AER protocol can establish virtual connections between neurons, facilitating efficient hardware implementation of large-scale impulse neural networks (Spiking Neural Network, SNN). The coding information is output in an asynchronous transmission protocol mode, so that the starting time of each pixel unit in the pixel unit array for outputting the coding information to the outside can be different, the problems of transmission congestion and the like when a large number of pixel units burst and transmit a large amount of data simultaneously can be solved, the data loss is avoided, and the data transmission efficiency and the transmission bandwidth utilization rate are improved.

After the coding sequence of the pixel unit is obtained and transmitted outwards based on the embodiment of the disclosure, the coding sequence corresponding to the pixel unit can be decoded at the receiving end to obtain a corresponding decoding result sequence. The decoding result sequence comprises decoding results corresponding to at least one pulse signal based on a time sequence relation, and each decoding result comprises time information of a coding time period corresponding to the pulse signal with a changed pulse width and the number of the pulse signals corresponding to the coding time period. Based on the decoding result sequence corresponding to the pixel unit, and the time information of the coding time period and the pulse signal information corresponding to the coding time period in the decoding result, the pulse width of the pulse signal corresponding to the decoding result can be determined.

The specific determination mode can be determined according to the time information in the decoding result and the meaning of the number of pulse signals.

For example, if the target pulse signal is encoded by using the pulse start time of the target pulse signal output from the clock circuit as the time information to be encoded and using the pulse count value obtained by counting the number of pulse signals of the same pulse width adjacent to the target pulse signal by the pulse count counter as the number of pulse signals to be encoded, the number of pulses in which the pulse width in the encoding period corresponding to the latter encoding information is the same as the pulse width in the encoding period can be determined based on each two adjacent encoding information, and the pulse width of each pulse signal in each period corresponding to the pixel unit can be determined by the ratio of the encoding period and the pulse number.

For example, if the pulse start time of the pulse signal of the same pulse width adjacent to the target pulse signal output by the clock circuit is used as the time information to be encoded, and the pulse count value obtained by counting the number of the pulse signals of the same pulse width by the pulse count counter is used as the number of the pulse signals to be encoded, the encoding time period (including the time between the time information in the previous encoding information and the time information in the next encoding information) corresponding to the previous encoding information and the number of pulses having the same pulse width in the encoding time period can be determined based on each two adjacent encoding information, and the pulse width of each pulse signal in the corresponding space of the pixel unit in each time period can be determined by the ratio of the encoding time period and the number of pulses.

For example, if the pulse end time of the target pulse signal output by the clock circuit is used as the time information to be encoded, and the number of pulse signals between the pulse end time of the previous target pulse signal adjacent to the target pulse signal and the pulse end time of the target pulse signal is counted by the pulse number counter to be used as the number of pulse signals to be encoded, the pulse width of the target pulse signal generated by the time information in the next encoded information can be determined based on each two adjacent encoded information, and the number and pulse width of other pulse signals in the encoded time period can be determined based on the pulse width of the target pulse signal, the same pulse number in the encoded time period, and the pulse width in the previous encoded information, thereby determining the pulse width of each pulse signal in the corresponding space of the pixel unit in each time period. For example, the time information t in the latter encoded information i can be determined as follows _i Pulse width τ of target pulse signal generated _i ：t _i -t _i-1 -(C _i-1 )τ _i-1 Wherein i is the order of the coding results in the same coding sequence, i is an integer greater than 1, t represents time information, and C represents pulse signal information.

In a specific implementation, each decoding result in the decoding result sequence is encoded data before encoding each encoding information, and its format may be expressed as (x, y, t) _i ,C _i ) Wherein i represents each decoding resultIn the sequence of the decoding results. The time information t in each encoding result i can be determined as follows _i Pulse width τ of target pulse signal generated _i ：t _i -t _i-1 -(C _i-1 )τ _i-1 For example, with the coding period (62.5,77) in fig. 6]Pulse calculation of the target pulse signal generated at the end time of the 77 th unit cycle is exemplified by the previous encoding period (32.5,42.5]The pulse width of the target pulse signal outputted at the end of the 77 th unit period is (x, y,77,3), and the pulse width is 77-42.5- (3-1) x 10=14.5, which is equal to the actual pulse width of the target pulse signal.

Further, after the pulse width of the pulse signal corresponding to each decoding result in the decoding result sequence corresponding to the space is based, the corresponding instant light intensity value can be determined based on the pulse width of each pulse signal. Based on the light intensity values of the entire observation scene, image reconstruction can be performed or directly used for target detection.

Alternatively, the light intensity value of the space corresponding to the decoding result may be determined based on the sequence of decoding results corresponding to the space, and the time information of the encoding time period and the number of pulse signals corresponding to the encoding time period in the decoding result.

For example, the light intensity value I spatially corresponding to each encoding period may be obtained by: i=k×c/T. Wherein, T is the duration of the encoding time period corresponding to the decoding result, C represents the number of pulse signals generated in the encoding time period, k is a constant greater than zero, and the specific value of k can be set according to the actual requirement.

Based on the light intensity values of the entire observation scene, image reconstruction can be performed or directly used for target detection.

In addition, the embodiment of the disclosure provides a photoelectric sensor, which includes a plurality of pixel units, wherein the pixel units can be implemented by adopting any one of the embodiments of the disclosure.

The pixel units can be arranged to form a pixel unit array, each pixel unit in the pixel unit array respectively carries out time domain sampling on the light signal in a designated space in the whole observation scene, the spaces corresponding to different pixel units in the pixel unit array are not overlapped, each pixel unit in the pixel unit array is matched with each other to cover the whole observation scene, and therefore the sampling on the light signal in the whole observation scene can be realized.

In addition, the embodiment of the disclosure provides a pulse camera, which comprises the photoelectric sensor provided by the embodiment of the disclosure.

In addition, an embodiment of the present disclosure provides an electronic device including:

the processor may be configured to perform the steps of,

a memory communicatively coupled to the processor;

a pixel unit or a photosensor connected to the processor. The pixel units or the photoelectric sensors can be realized by adopting any embodiment of the disclosure.

Optionally, in some implementations, the electronic device may include, but is not limited to, any one of the following: integrated circuits, sensors, etc.

Optionally, in some implementations, the electronic device may include, for example, but is not limited to, or be incorporated into any of the following: pulse cameras, high-speed cameras, audio/video players, navigation devices, fixed location terminals, entertainment units, smartphones, communication devices, devices in motor vehicles, cameras, motion or wearable cameras, detection devices, flying devices, medical devices, security devices, and the like.

Fig. 7 is a schematic structural diagram of an application embodiment of the electronic device of the present disclosure. Next, an electronic device according to an embodiment of the present disclosure is described with reference to fig. 7. The electronic device may be either or both of the first device and the second device, or a stand-alone device independent thereof, which may communicate with the first device and the second device to receive the acquired input signals therefrom.

As shown in fig. 7, the electronic device includes a pixel cell or photosensor, one or more processors, and memory. The processor may be a Central Processing Unit (CPU) or other form of processing unit having data processing and/or instruction execution capabilities, and may control other components in the electronic device to perform the desired functions.

The memory may include one or more computer program products that may include various forms of computer-readable storage media, such as volatile memory and/or non-volatile memory. The volatile memory may include, for example, random Access Memory (RAM) and/or cache memory (cache), and the like. The non-volatile memory may include, for example, read Only Memory (ROM), hard disk, flash memory, and the like. One or more computer program instructions may be stored on the computer readable storage medium that can be executed by a processor to implement the encoding of optical signals to control a pixel cell or photosensor to perform a corresponding action for various embodiments of the present disclosure as described above.

In one example, the electronic device may further include: input devices and output devices, which are interconnected by a bus system and/or other forms of connection mechanisms (not shown).

In addition, the input device may include, for example, a keyboard, a mouse, and the like.

The output device may output various information including the determined distance information, direction information, etc., to the outside. The output devices may include, for example, a display, speakers, a printer, and a communication network and remote output devices connected thereto, etc.

Of course, only some of the components of the electronic device relevant to the present disclosure are shown in fig. 7 for simplicity, components such as buses, input/output interfaces, and the like being omitted. In addition, the electronic device may include any other suitable components depending on the particular application.

The computer program product may write program code for performing the operations of embodiments of the present disclosure in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device, partly on a remote computing device, or entirely on the remote computing device or server.

The computer readable storage medium may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may include, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium would include the following: an electrical connection having one or more wires, a portable disk, a hard disk, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

The basic principles of the present disclosure have been described above in connection with specific embodiments, however, it should be noted that the advantages, benefits, effects, etc. mentioned in the present disclosure are merely examples and not limiting, and these advantages, benefits, effects, etc. are not to be considered as necessarily possessed by the various embodiments of the present disclosure. Furthermore, the specific details disclosed herein are for purposes of illustration and understanding only, and are not intended to be limiting, since the disclosure is not necessarily limited to practice with the specific details described.

In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different manner from other embodiments, so that the same or similar parts between the embodiments are mutually referred to.

The block diagrams of the devices, apparatuses, devices, systems referred to in this disclosure are merely illustrative examples and are not intended to require or imply that the connections, arrangements, configurations must be made in the manner shown in the block diagrams. As will be appreciated by one of skill in the art, the devices, apparatuses, devices, systems may be connected, arranged, configured in any manner. Words such as "including," "comprising," "having," and the like are words of openness and mean "including but not limited to," and are used interchangeably therewith. The terms "or" and "as used herein refer to and are used interchangeably with the term" and/or "unless the context clearly indicates otherwise. The term "such as" as used herein refers to, and is used interchangeably with, the phrase "such as, but not limited to.

The present disclosure may be implemented in many ways. For example, the present disclosure may be implemented in hardware, firmware, or any combination of hardware and firmware. It is also noted that in the apparatus, devices of the present disclosure, the components may be disassembled and/or assembled. Such decomposition and/or recombination should be considered equivalent to the present disclosure.

The previous description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the disclosure. Thus, the present disclosure is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The foregoing description has been presented for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the disclosure to the form disclosed herein. Although a number of example aspects and embodiments have been discussed above, a person of ordinary skill in the art will recognize certain variations, modifications, alterations, additions, and subcombinations thereof.

Claims

1. A pixel cell of a photosensor, comprising: a pulse generating circuit, a pulse width counter, a first comparator and a pulse number counter;

the pulse width counter is connected with the first comparator;

The first comparator is connected with the pulse number counter.

2. The pixel cell of claim 1, further comprising: a pulse width memory;

3. The pixel cell of claim 2, wherein the pulse generation circuit comprises: a photodiode, a reset transistor, and a second comparator;

the positive input end of the second comparator is connected with an external reference signal, the negative input end of the second comparator is connected with the negative electrode of the photodiode, and the output end of the second comparator is respectively connected with the grid electrode of the reset transistor, the pulse width counter and the first comparator.

4. A pixel cell according to any one of claims 1-3, further comprising: a clock circuit;

5. The pixel cell of claim 4, further comprising: a scanning circuit;

6. The pixel cell of claim 5, further comprising: an encoder;

the encoder is respectively connected with the pulse number counter, the clock circuit and the scanning circuit.

7. A photoelectric sensor, comprising: a plurality of pixel cells according to any one of claims 1-6.

8. A pulse camera comprising the photosensor of claim 7.

9. An electronic device, comprising:

the processor may be configured to perform the steps of,

a memory communicatively coupled to the processor;

a pixel cell according to any one of claims 1-6 or a photosensor according to claim 7, connected to the processor.

10. The electronic device of claim 9, wherein the electronic device is incorporated as any one of: pulse cameras, high-speed cameras, audio/video players, navigation devices, fixed location terminals, entertainment units, smartphones, communication devices, devices in motor vehicles, cameras, motion or wearable cameras, detection devices, flight devices, medical devices, security devices.