Pixel unit and signal reading method thereof

Abstract

The invention belongs to the field of photoelectric conversion, and discloses a pixel unit and a signal reading method thereof, and the pixel unit comprises a detection array, a signal conversion module and a driving module which are connected in sequence; the detection array comprises a plurality of macro pixel arrays and a plurality of switches, the macro pixel arrays are sequentially arranged according to a set interval, each macro pixel array comprises a plurality of pixel modules, the pixel modules are sequentially arranged, and the pixel modules are correspondingly connected with the switches according to a set sequence. According to the technical scheme, the crosstalk problem between the adjacent pixel units in the detector array can be solved.

Description

Technical Field

[0001] The invention belongs to the field of photoelectric detection, and in particular relates to a pixel unit and a signal readout method thereof. Background Art

[0002] Photodetectors are devices that convert optical signals into electrical signals. They are widely used in optical communications, imaging, spectral analysis and other fields. Photodetector arrays are two-dimensional arrays composed of multiple photodetector units, which can achieve high-resolution detection and imaging of optical signals in two-dimensional space. However, in the photoelectric conversion system based on the photodetector array, the photoelectric crosstalk between the pixels in the detector array is the main factor affecting the system resolution. The crosstalk in the photodetector array is mainly divided into optical crosstalk and electrical crosstalk. Optical crosstalk mainly refers to the crosstalk caused by the absorption of the incident light by the adjacent pixels. Electrical crosstalk refers to the crosstalk caused by the non-equilibrium carriers generated when the incident light enters the photosensitive area and diffuses laterally into the adjacent pixels and is collected by the adjacent pixels. Therefore, the closer the distance between the pixels in the array, the more serious the crosstalk phenomenon will be, which will lead to problems such as impaired imaging quality and reduced detection accuracy in the application scenario. Summary of the invention

[0003] The object of the present invention is to provide a pixel unit and a signal readout method thereof to solve the problems existing in the above-mentioned prior art.

[0004] To achieve the above object, the present invention provides a pixel unit, comprising a detection array, a signal conversion module and a driving module connected in sequence;

[0005] The detection array includes a plurality of macro-pixel arrays and a plurality of switches, each of the macro-pixel arrays is arranged in sequence at set intervals, each of the macro-pixel arrays includes a plurality of pixel modules, each of the pixel modules is arranged in sequence, and each of the pixel modules is connected one-to-one with each of the switches in the same arrangement order.

[0006] Optionally, each of the pixel modules is connected to the signal conversion module via an output bus.

[0007] Optionally, one end of each switch away from the pixel module is electrically connected to a bias voltage output module.

[0008] A signal readout method, applied to the above-mentioned pixel unit, is characterized by comprising:

[0009] The switches are controlled to be turned on according to the arrangement sequence of the switches, bias voltages are sequentially provided to the macro-pixel arrays according to the arrangement sequence of the macro-pixel arrays, so that the pixel modules in the macro-pixel arrays work in a test state in turn, an optical signal is input to each pixel module to generate a photocurrent, and the photocurrent is input to the signal conversion module through the output bus for signal conversion and amplification to obtain an amplified voltage signal, and the amplified voltage signal is output after passing through a driver.

[0010] A pixel unit comprises a detection array, a signal conversion module and a driving module connected in sequence;

[0011] The detection array includes a plurality of macro-pixel arrays and a plurality of switches, wherein the macro-pixel array includes a first macro-pixel array and a second macro-pixel array arranged in sequence at set intervals; the switches include a first switch, a second switch, a third switch and a fourth switch arranged in sequence; each of the macro-pixel arrays is connected to each of the switches; and each of the switches is electrically connected to a bias voltage output module at one end away from the macro-pixel array.

[0012] Optionally, the first macro pixel array includes a first pixel array and a second pixel array arranged in parallel; the first pixel array is connected to a first output port, and the second pixel array is connected to a second output port; the first pixel array includes a first pixel module, a second pixel module, a third pixel module and a fourth pixel module arranged in sequence, and the second pixel array includes a fifth pixel module, a sixth pixel module, a seventh pixel module and an eighth pixel module arranged in sequence;

[0013] The first pixel module and the third pixel module are connected to the first switch, the second pixel module and the fourth pixel module are connected to the third switch, the fifth pixel module and the seventh pixel module are connected to the second switch, and the sixth pixel module and the eighth pixel module are connected to the fourth switch;

[0014] The first pixel module, the second pixel module, the third pixel module and the fourth pixel module are all connected to the first output port; the fifth pixel module, the sixth pixel module, the seventh pixel module and the eighth pixel module are all connected to the second output port.

[0015] Optionally, the second macro pixel array includes a third pixel array and a fourth pixel array arranged in parallel; the third pixel array is connected to a third output port, and the fourth pixel array is connected to a fourth output port; the third pixel array includes a ninth pixel module, a tenth pixel module, an eleventh pixel module and a twelfth pixel module arranged in sequence, and the fourth pixel array includes a thirteenth pixel module, a fourteenth pixel module, a fifteenth pixel module and a sixteenth pixel module arranged in sequence;

[0016] The ninth pixel module and the eleventh pixel module are connected to the first switch, the tenth pixel module and the twelfth pixel module are connected to the third switch, the thirteenth pixel module and the fifteenth pixel module are connected to the second switch, and the fourteenth pixel module and the sixteenth pixel module are connected to the fourth switch;

[0017] The ninth pixel module, the tenth pixel module, the eleventh pixel module and the twelfth pixel module are all connected to the third output port; the thirteenth pixel module, the fourteenth pixel module, the fifteenth pixel module and the sixteenth pixel module are all connected to the third output port.

[0018] A signal reading method, using the above-mentioned pixel unit, comprises:

[0019] The switches are controlled to be turned on according to the arrangement sequence of the switches, bias voltages are sequentially provided to the macro-pixel arrays according to the arrangement sequence of the macro-pixel arrays, so that the pixel modules in the macro-pixel arrays work in a test state in turn, and optical signals are input into the pixel modules to generate photocurrents. The photocurrents are input into the signal conversion modules through the output ports to perform signal conversion and amplification to obtain amplified voltage signals, which are then outputted after passing through the driver.

[0020] The technical effects of the present invention are:

[0021] The present invention divides the pixel modules into a macro pixel array at a certain interval, and performs independent power supply, signal acquisition and readout for each macro pixel. In this way, the distance between each pixel module in the macro pixel is increased, thereby improving the crosstalk problem between adjacent pixel modules in the detector array. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0024] Figure 1 is a diagram of the detector array architecture in an embodiment of the present invention;

[0025] Figure 2is a schematic structural diagram of a pixel unit in an embodiment of the present invention;

[0026] Figure 3 is a diagram of a 16×1 pixel array architecture in an embodiment of the present invention;

[0027] Figure 4 It is a schematic diagram of the structure of a pixel unit using a 16×1 pixel array in an embodiment of the present invention;

[0028] Figure 5 FIG. 4 is a diagram of a 4×4 pixel array architecture in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0030] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0031] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those of ordinary skill in the art generally understood by the present invention. Although the present invention describes only preferred methods, any method similar or equivalent to that described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0032] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present application description and examples are exemplary only.

[0033] The words “include,” “including,” “have,” “contain,” etc. used in this article are open-ended terms, meaning including but not limited to.

[0034] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] Embodiment 1

[0036] like Figure 1 - Figure 4 As shown, this embodiment provides a pixel unit, including a detection array, a signal conversion module and a driving module connected in sequence;

[0037] The detection array includes a plurality of macro-pixel arrays and a plurality of switches, each of the macro-pixel arrays is arranged in sequence at set intervals, each of the macro-pixel arrays includes a plurality of pixel modules, each of the pixel modules is arranged in sequence, and each of the pixel modules is connected one-to-one with each of the switches in the same arrangement order.

[0038] Each of the pixel modules is connected to the signal conversion module via an output bus.

[0039] One end of each switch away from the pixel module is electrically connected to a bias voltage output module.

[0040] A signal readout method, applied to the above-mentioned pixel unit, is characterized by comprising:

[0041] The switches are controlled to be turned on according to the arrangement sequence of the switches, bias voltages are sequentially provided to the macro-pixel arrays according to the arrangement sequence of the macro-pixel arrays, so that the pixel modules in the macro-pixel arrays work in a test state in turn, an optical signal is input to each pixel module to generate a photocurrent, and the photocurrent is input to the signal conversion module through the output bus for signal conversion and amplification to obtain an amplified voltage signal, and the amplified voltage signal is output after passing through a driver.

[0042] Specifically, the detector array structure of this embodiment is described as follows: the detector array is composed of a pixel array of s×t scale, where s=(1+n)a; s, t, a, and n are all positive integers.

[0043] The detector array architecture is as follows Figure 1 As shown, (1+n)a detector pixel modules form a column, wherein every n+1 pixel modules form a macro pixel, and power supply and signal readout are performed uniformly.

[0044] Macro pixel 1 is composed of pixel module 1, pixel module 1+a, pixel module 1+2a, ..., pixel module 1+na; macro pixel 2 is composed of pixel module 2, pixel module 2+a, pixel module 2+2a, ..., pixel module 2+na; macro pixel 3 is composed of pixel module 3, pixel module 3+a, pixel module 3+2a, ..., pixel module 3+na; ...; macro pixel a is composed of pixel module a, pixel module 2a, pixel module 3a, ..., pixel module (1+n)a. The detector bias voltage in the detector array is provided by the power supply port Vsup, which is connected to the bias voltage port of macro pixel 1 through switch S[1], connected to the bias voltage port of macro pixel 2 through switch S[2], connected to the bias voltage port of macro pixel 3 through switch S[3], ..., connected to the bias voltage port of macro pixel a through switch S[a].

[0045] The power supply port provides k bias voltages, k is a positive integer, and the specific value is determined by the number of bias voltages required by the photodetector. The output ends of all pixel modules in the detector array are connected to the column output bus Vout. The pixel unit is composed of a detector unit, a signal conversion module and a driver; the output end of the detector unit is connected to the input end of the signal conversion module, and the output end of the signal conversion module is connected to the input end of the driver; the working process of the pixel module is: the bias voltage Vsup[1:k] provides k bias voltages to the detector unit, the detector unit in the biased state receives the input light signal, and the generated photocurrent is converted into a voltage signal and amplified by the signal conversion module, and then output to the array signal bus through the driver.

[0046] The detector array signal readout method is as follows: control switches S[1]-S[a] to be turned on respectively, and bias voltages are provided to macropixels 1-a in turn, so that each macropixel works in the test state in turn, and the output signal of each pixel module is received in turn at the output bus end.

[0047] like Figure 3 As shown, the detector array used in this embodiment is composed of a 16×1 pixel array, and 16 detector pixel modules form a column, wherein every 4 pixel modules constitute a macro pixel, and power supply and signal readout are performed uniformly.

[0048] Macro pixel 1 is composed of pixel module 1, pixel module 5, pixel module 9 and pixel module 13; macro pixel 2 is composed of pixel module 2, pixel module 6, pixel module 10 and pixel module 14; macro pixel 3 is composed of pixel module 3, pixel module 7, pixel module 11 and pixel module 15; macro pixel 4 is composed of pixel module 4, pixel module 8, pixel module 12 and pixel module 16. The detector bias voltage in the detector array is provided by power supply ports Vsup[1] and Vsup[2], connected to the bias voltage port of macro pixel 1 through switch S[1]; connected to the bias voltage port of macro pixel 2 through switch S[2]; connected to the bias voltage port of macro pixel 3 through switch S[3]; connected to the bias voltage port of macro pixel 4 through switch S[4].

[0049] The output ends of all pixel modules in the detector array are connected to the column output bus Vout. The signal conversion module uses a transimpedance amplifier. The pixel unit consists of a balanced detector unit, a transimpedance amplifier and a driver; the output end of the balanced detector unit is connected to the input end of the transimpedance amplifier, and the output end of the transimpedance amplifier is connected to the input end of the driver. The working process of the pixel unit is as follows: the bias voltage Vsup[1:2] provides a bias voltage to the two power supply ports of the balanced detector, and the balanced detector unit in the biased state receives the input light signal. The generated photocurrent is converted into a voltage signal and amplified by the transimpedance amplifier, and then output to the array signal bus through the driver.

[0050] The detector array signal readout method is as follows: control switches S[1]-S[4] to be turned on respectively, and bias voltages are provided to macro pixels 1-4 in turn, so that each macro pixel works in a test state in turn, and receives output signals at the output bus end.

[0051] In this embodiment, the pixel modules are divided into a macro-pixel array at a certain interval, and each macro-pixel is powered, signal collected and read out separately. In this way, the distance between each pixel module in the macro-pixel is increased, thereby improving the crosstalk problem between adjacent pixel modules in the detector array.

[0052] Embodiment 2

[0053] like Figure 5 As shown, a pixel unit is provided in this embodiment, including a detection array, a signal conversion module and a driving module connected in sequence; the detection array includes a plurality of macro-pixel arrays and a plurality of switches, the macro-pixel array includes a first macro-pixel array and a second macro-pixel array arranged in sequence at set intervals; the switch includes a first switch, a second switch, a third switch and a fourth switch arranged in sequence; each of the macro-pixel arrays is connected to each of the switches; and each of the switches is electrically connected to a bias voltage output module at one end away from the macro-pixel array.

[0054] A signal readout method is applied to a pixel unit described in Example 2, comprising: controlling each of the switches to be turned on according to the arrangement order of each of the switches, providing bias voltages to each of the macro-pixel arrays in sequence according to the arrangement order of each of the macro-pixel arrays, so that the pixel modules in each of the macro-pixel arrays work in a test state in sequence, inputting an optical signal into each of the pixel modules to generate a photocurrent, and inputting the photocurrent into the signal conversion module through each output port for signal conversion and amplification to obtain an amplified voltage signal, and outputting the amplified voltage signal after passing through a driver.

[0055] The detector array used in this embodiment is composed of a 4×4 pixel array. The detector array architecture is as follows: Figure 5 As shown, 16 detector pixel modules form a 4×4 array, wherein every 4 pixel modules form a macro pixel, which are uniformly powered and signal readout.

[0056] More specifically, macro pixel 1 is composed of pixel module 1_1, pixel module 1_3, pixel module 3_1 and pixel module 3_3; macro pixel 2 is composed of pixel module 1_2, pixel module 1_4, pixel module 3_2 and pixel module 3_4; macro pixel 3 is composed of pixel module 2_1, pixel module 2_3, pixel module 4_1 and pixel module 4_3; macro pixel 4 is composed of pixel module 2_2, pixel module 2_4, pixel module 4_2 and pixel module 4_4. The detector bias voltage in the detector array is provided by power supply ports Vsup[1] and Vsup[2], connected to the bias voltage port of macro pixel 1 through switch S[1]; connected to the bias voltage port of macro pixel 2 through switch S[2]; connected to the bias voltage port of macro pixel 3 through switch S[3]; connected to the bias voltage port of macro pixel 4 through switch S[4].

[0057] All pixel module outputs in the detector array are connected to the column output bus Vout[1:4].

[0058] The pixel unit is composed of a balanced detector unit, a transimpedance amplifier and a driver; the output end of the balanced detector unit is connected to the input end of the transimpedance amplifier, and the output end of the transimpedance amplifier is connected to the input end of the driver. The working process of the pixel unit is as follows: the bias voltage Vsup[1:2] provides a bias voltage to the two power supply ports of the balanced detector, the balanced detector unit in the biased state receives the input light signal, and the generated photocurrent is converted into a voltage signal and amplified by the transimpedance amplifier, and then output to the array signal bus through the driver.

[0059] The detector array signal readout method of this embodiment is as follows: control switches S[1]-S[4] to be turned on respectively, and bias voltages are provided to macro pixels 1-4 in turn, so that each macro pixel works in a test state in turn, and the output signal of each pixel module is received in turn at the output bus end.

[0060] In this embodiment, the pixel modules in the detector array are divided into macro-pixel arrays at certain intervals, and exposure and signal readout are performed sequentially; in this way, the physical interval between the detectors that collect light signals at the same time is increased, and the crosstalk problem between adjacent detector units is improved.

[0061] The above is only a preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A pixel unit, characterized in that: It includes a detection array, a signal conversion module and a driving module connected in sequence; The detection array includes a plurality of macro-pixel arrays and a plurality of switches, each of the macro-pixel arrays is arranged in sequence at set intervals, each of the macro-pixel arrays includes a plurality of pixel modules, each of the pixel modules is arranged in sequence, and each of the pixel modules is connected one-to-one with each of the switches in the same arrangement order.

2. A pixel unit according to claim 1, characterized in that: Each of the pixel modules is connected to the signal conversion module via an output bus.

3. A pixel unit according to claim 1, characterized in that: One end of each switch away from the pixel module is electrically connected to a bias voltage output module.

4. A signal readout method, applied to a pixel unit according to any one of claims 1 to 3, characterized in that: include: The switches are controlled to be turned on according to the arrangement sequence of the switches, bias voltages are sequentially provided to the macro-pixel arrays according to the arrangement sequence of the macro-pixel arrays, so that the pixel modules in the macro-pixel arrays work in a test state in turn, an optical signal is input to each pixel module to generate a photocurrent, and the photocurrent is input to the signal conversion module through the output bus for signal conversion and amplification to obtain an amplified voltage signal, and the amplified voltage signal is output after passing through a driver.

5. A pixel unit, characterized in that: It includes a detection array, a signal conversion module and a driving module connected in sequence; The detection array includes a plurality of macro-pixel arrays and a plurality of switches, wherein the macro-pixel array includes a first macro-pixel array and a second macro-pixel array arranged in sequence at set intervals; the switches include a first switch, a second switch, a third switch and a fourth switch arranged in sequence; each of the macro-pixel arrays is connected to each of the switches; and each of the switches is electrically connected to a bias voltage output module at one end away from the macro-pixel array.

6. A pixel unit according to claim 5, characterized in that: The first macro pixel array includes a first pixel array and a second pixel array arranged in parallel; the first pixel array is connected to a first output port, and the second pixel array is connected to a second output port; the first pixel array includes a first pixel module, a second pixel module, a third pixel module and a fourth pixel module arranged in sequence, and the second pixel array includes a fifth pixel module, a sixth pixel module, a seventh pixel module and an eighth pixel module arranged in sequence; The first pixel module and the third pixel module are connected to the first switch, the second pixel module and the fourth pixel module are connected to the third switch, the fifth pixel module and the seventh pixel module are connected to the second switch, and the sixth pixel module and the eighth pixel module are connected to the fourth switch; The first pixel module, the second pixel module, the third pixel module and the fourth pixel module are all connected to the first output port; the fifth pixel module, the sixth pixel module, the seventh pixel module and the eighth pixel module are all connected to the second output port.

7. A pixel unit according to claim 5, characterized in that: The second macro pixel array includes a third pixel array and a fourth pixel array arranged in parallel; the third pixel array is connected to a third output port, and the fourth pixel array is connected to a fourth output port; the third pixel array includes a ninth pixel module, a tenth pixel module, an eleventh pixel module, and a twelfth pixel module arranged in sequence, and the fourth pixel array includes a thirteenth pixel module, a fourteenth pixel module, a fifteenth pixel module, and a sixteenth pixel module arranged in sequence; The ninth pixel module and the eleventh pixel module are connected to the first switch, the tenth pixel module and the twelfth pixel module are connected to the third switch, the thirteenth pixel module and the fifteenth pixel module are connected to the second switch, and the fourteenth pixel module and the sixteenth pixel module are connected to the fourth switch; The ninth pixel module, the tenth pixel module, the eleventh pixel module and the twelfth pixel module are all connected to the third output port; the thirteenth pixel module, the fourteenth pixel module, the fifteenth pixel module and the sixteenth pixel module are all connected to the third output port.

8. A signal readout method, applied to a pixel unit according to any one of claims 5 to 7, characterized in that: include: The switches are controlled to be turned on according to the arrangement sequence of the switches, bias voltages are sequentially provided to the macro-pixel arrays according to the arrangement sequence of the macro-pixel arrays, so that the pixel modules in the macro-pixel arrays work in a test state in turn, and optical signals are input to the pixel modules to generate photocurrents. The photocurrents are input to the signal conversion modules through the output ports to perform signal conversion and amplification to obtain amplified voltage signals, which are then outputted after passing through the driver.

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