WO2021128595A1 - 一种可随机读取的有源像素电路及其驱动方法 - Google Patents

一种可随机读取的有源像素电路及其驱动方法 Download PDF

Info

Publication number
WO2021128595A1
WO2021128595A1 PCT/CN2020/078925 CN2020078925W WO2021128595A1 WO 2021128595 A1 WO2021128595 A1 WO 2021128595A1 CN 2020078925 W CN2020078925 W CN 2020078925W WO 2021128595 A1 WO2021128595 A1 WO 2021128595A1
Authority
WO
WIPO (PCT)
Prior art keywords
transistor
photodiode
gate
pixel circuit
active pixel
Prior art date
Application number
PCT/CN2020/078925
Other languages
English (en)
French (fr)
Inventor
王凯
许忆彤
齐一泓
石睿
Original Assignee
中山大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中山大学 filed Critical 中山大学
Publication of WO2021128595A1 publication Critical patent/WO2021128595A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof

Definitions

  • the invention belongs to the technical field of circuits, and in particular relates to an active pixel circuit capable of being read randomly and a driving method thereof.
  • a conventional active pixel circuit usually includes three transistors (reset switch transistor Trst, source follower Tsf, and select switch transistor Tsel) and a photodiode. If the gate and drain of the reset switch transistor Trst are short-circuited, a Logarithmic Active Pixel Sensor (Log. APS) as shown in FIG. 1 can be formed.
  • the output signal of Log.APS changes logarithmically with the change of light intensity, so it has a wider dynamic response range, generally at least 100dB or more.
  • Log.APS does not need to reset the sensor, the circuit is simple, the pixel fill factor is larger, and the operation is faster and simpler.
  • each pixel in Log.APS works independently and the photo-generated charge does not need to be time-integrated during the photoelectric conversion process, so it can be read randomly in space and time, and the random readability in space allows independent Reading and processing important signals makes the sensor more intelligent, and the random readability in time allows the signal to be read out and processed more quickly, so the random readability of space and time makes the signal effective The read speed is faster.
  • the device connection method inside the Log.APS pixel causes the output signal to decrease with the increase of the light intensity, so that the back-end signal readout and processing circuit needs to be redesigned. Moreover, it is precisely because the Log.APS output has a logarithmic relationship with the input, the sensitivity of the sensor under low light is relatively low. Finally, the design of the active pixel using three transistors also makes it difficult to further reduce the pixel size, which in turn affects the sensitivity of the pixel.
  • the present invention provides a random read active pixel sensor circuit, which can improve the sensitivity and dynamic range of the random read active pixel sensor circuit.
  • An active pixel circuit capable of being read randomly, comprising: a photodiode, a first transistor, a second transistor, a first power supply, and a second power supply;
  • the first power supply is connected to the drain of the second transistor and connected to the drain of the first transistor through the diode.
  • the drain of the first transistor is connected to the gate of the first transistor and the The top gate of the second transistor is connected, the source of the first transistor is grounded, the bottom gate of the second transistor is connected to the second power source, and the source of the second transistor is a signal output terminal.
  • the beneficial effect of this circuit is: on the basis of Log.APS, the two transistors, the source follower and the selection switch, are replaced with one transistor, so that the sensor circuit retains the random reading of Log.APS. While taking performance, it can also make the output and input have a linear relationship, so that the sensitivity and dynamic range of the sensor under low light are improved, and the number of active devices in the pixel is reduced, and the aperture ratio and filling of the pixel are also improved. factor.
  • the first transistor is a single-gate transistor
  • the second transistor is a double-gate transistor
  • the photodiode is a diode with a nip structure
  • the first transistor and the second transistor are both n-type semiconductor devices
  • the first power supply is connected to the cathode of the photodiode, so The anode of the photodiode is connected to the drain of the first transistor.
  • the photodiode is a diode with a pin structure
  • the first transistor and the second transistor are p-type semiconductor devices
  • the first power supply is connected to the anode of the photodiode
  • the The cathode of the photodiode is connected to the drain of the first transistor.
  • the present invention also provides another active pixel circuit that can be read randomly, including: a photodiode, a first transistor, a second transistor, a first power supply, and a second power supply;
  • the first power supply is connected to the drain of the first transistor and the drain of the second transistor, the drain of the first transistor is connected to the gate of the first transistor, and the The source is connected to the top gate of the second transistor and is grounded through the photodiode, the bottom gate of the second transistor is connected to the second power source, and the source of the second transistor is a signal output terminal.
  • the first transistor is a single-gate thin film transistor
  • the second transistor is a double-gate thin film transistor
  • the photodiode is a diode with a nip structure
  • the first transistor and the second transistor are both n-type semiconductor devices
  • the cathode of the diode and the source of the first transistor are The top gate of the second transistor is connected, and the anode of the diode is grounded.
  • the photodiode is a pin structure photodiode
  • the first transistor and the second transistor are both p-type semiconductor devices
  • the anode of the photodiode is connected to the source of the first transistor.
  • the top gate of the second transistor are connected, and the cathode of the photodiode is grounded.
  • the present invention also provides a driving method of an active pixel circuit capable of being read randomly as described above, which includes the following steps:
  • the randomly readable active pixel circuit When the randomly readable active pixel circuit is in the working state, a voltage is applied to the photodiode to make the photodiode in a reverse-biased state, and a photocurrent is generated under illumination, so that the first transistor, The second transistor operates in a sub-threshold region, so that the output current of the active pixel circuit that can be read randomly and the photocurrent of the photodiode have a power function relationship.
  • the beneficial effect of this method is that the output current of the active pixel circuit that can be read randomly and the photocurrent of the diode are in a power function relationship, and the output signal and light intensity of the sensor circuit are similarly linear. Relationship, forming a logarithmic-exponential pixel circuit, so the sensitivity and dynamic response range of the sensor can be optimized at the same time.
  • Figure 1 is a schematic diagram of a conventional logarithmic active pixel circuit
  • FIG. 2 is a schematic diagram of the active pixel circuit according to the first embodiment
  • FIG. 3 is a schematic diagram of the active pixel circuit described in the second embodiment
  • FIG. 5 is a schematic diagram of the active pixel circuit described in the fourth embodiment.
  • This embodiment discloses an active pixel circuit that can be read randomly, as shown in FIG. 2, including: a photodiode D, a single-gate thin film transistor TFT1, a double-gate thin film transistor TFT2, a first power supply V DD and a double-gate thin film transistor
  • the drain of TFT2 is connected, and the anode of photodiode D is connected to the drain of single-gate thin film transistor TFT1, the cathode of photodiode D is connected to the first power supply V DD , and the drain of single-gate thin film transistor TFT1 is connected to single-gate thin film transistor TFT1.
  • the gate of the double gate thin film transistor TFT2 is connected to the top gate, the source of the single gate thin film transistor TFT1 is grounded, the bottom gate of the double gate thin film transistor TFT2 is connected to the second power supply V BG , and the source of the double gate thin film transistor TFT2 is signal output
  • the first power supply V DD is used to provide a reverse bias voltage for the photodiode D
  • the second power supply V BG is used to control the double-gate thin film transistor.
  • the photodiode D is a photodiode with an n-i-p structure, which can use a variety of diodes such as amorphous silicon diodes or organic diodes or similar photodetectors.
  • the active layer material of the single-gate thin film transistor TFT1 and the active layer material of the double-gate thin film transistor TFT2 are both amorphous silicon, indium gallium zinc oxide, n-type organic semiconductor, n-type low-temperature polysilicon, etc.
  • a type of material, the dual-gate thin film transistor TFT2 is used to replace the source follower and selection switch in Log APS, which reduces the number of internal components of the pixel and improves the aperture ratio and fill factor of the pixel.
  • the circuit is improved, so that the output and input of the pixel are in a linear positive correlation relationship while maintaining the random readability in space and time, which facilitates the design of the back-end signal readout and signal processing circuit.
  • the photodiode D When the sensor pixel circuit is in working condition, the photodiode D needs to be reverse biased to make it light-sensitive. Therefore, the first power supply V DD and the second power supply V BG are both externally biased ports; a-Si, IGZO, n-type organic semiconductors and n-type low-temperature polysilicon are all n-type materials, which generally require positive voltage to drive, so the photodiode D with nip structure is adopted, that is, the cathode is used as the external bias port, and the anode is connected to TFT1 ⁇ Grid.
  • V DD When the sensor pixel circuit is working, V DD is forward biased, and the photodiode D is in a reverse biased state. At this time, the photo-generated carriers in the photodiode D generate electron-hole pairs due to the external bias.
  • the cathode and anode move to form a photocurrent I photo :
  • q is the element charge
  • ⁇ 0 is the quantum efficiency of the diode D
  • P is the light intensity
  • a PD is the photosensitive area of the diode D
  • ⁇ is the wavelength
  • R is the reflection coefficient
  • ⁇ and t are respectively the active layer of the diode D Absorption coefficient and thickness
  • h Planck's constant
  • c is the speed of light in vacuum. Therefore, the total current flowing through the diode D is:
  • I dark is the leakage current when the diode D is in reverse bias in the dark state.
  • the gate and drain are short-circuited, so the gate voltage V GS is equal to the source-drain voltage V DS1 :
  • V GS V DS1 (3)
  • the source and drain current I DS1 of TFT1 can be obtained as:
  • V T1 is the threshold voltage of the single-gate thin film transistor TFT1
  • S 1 is the sub-threshold swing amplitude of the single-gate thin film transistor TFT1
  • k is the Boltzmann constant
  • T is the temperature.
  • the source-drain voltage V DS1 of the single-gate thin film transistor TFT1 can be obtained as:
  • V T2 For the double-gate thin film transistor TFT2, its threshold voltage V T2 can be expressed as:
  • V T2 V TH0 + ⁇ V TG (8)
  • ⁇ is the control coefficient of the second gate voltage to the threshold voltage.
  • the output current I DS2 of the sub-threshold region of the double-gate thin film transistor TFT2 can be obtained as:
  • S 2 is the sub-threshold swing of the double-gate thin film transistor TFT2. when That is, when V DS2 >>0.0258V (at room temperature), formula (9) can be simplified as:
  • the final output current I DS2 of the active pixel sensor circuit that can be read at random is in a power function relationship with the photocurrent I photo of the diode D, namely:
  • the sub-threshold swing is basically the same, that is, S 1 ⁇ S 2 , so the output current I DS2 has a power function relationship with the light intensity P, namely:
  • the active pixel circuit based on the n-type semiconductor device designed in this embodiment retains the feature of random readability, and because the output of the pixel circuit is similar to the light intensity Linear relationship, under weak light intensity, the output current changes more obviously with light intensity, so it has higher sensitivity and wider dynamic response range.
  • This embodiment discloses another active pixel circuit that can be read randomly.
  • the difference from the first embodiment is that: the photodiode D is a photodiode with a pin structure, and the first power supply V DD and the photodiode The anode of D is connected, the cathode of the photodiode D is connected to the drain of the single-gate thin film transistor TFT1, the first power supply V DD is used to provide reverse bias voltage for the photodiode D, and the second power supply V BG is the double gate thin film transistor TFT2 Working voltage.
  • the active layer material of the single-gate thin film transistor TFT1 and the active layer material of the double-gate thin film transistor TFT2 are both p-type low-temperature polysilicon or p-type organic semiconductor and other p-type materials, using double-gate thin film
  • the transistor TFT2 replaces the source follower and selection switch in the Log APS, reduces the use of internal components of the pixel, increases the aperture ratio of the pixel and simplifies the production process.
  • the first power supply VDD When the sensor pixel circuit is in the working state, because it is composed of pin-type diodes and p-type thin film devices, the first power supply VDD must be negatively biased to allow the photodiode D to be in a reverse bias state and the thin film transistors to be in operation status.
  • the total current flowing through the photodiode D is:
  • the gate voltage and source-drain voltage of the single-gate thin film transistor TFT1 are also the same as formula (3), that is, the gate voltage is equal to the source-drain voltage. From the current formula of the sub-threshold region of the p-type thin film transistor, the sub-threshold current I SD1 of TFT1 can be obtained as:
  • ⁇ 1 is an ideal parameter of the single-gate thin film transistor TFT1.
  • the source and drain voltage V DS1 of the single-gate thin film transistor TFT1 can be obtained as
  • the top gate voltage V TG and the threshold voltage V T2 of the double-gate thin film transistor TFT2 can be obtained.
  • the output current I SD2 of the sub-threshold region of the double-gate thin film transistor TFT2 can be obtained as:
  • the final output current I SD2 of the active pixel sensor circuit that can be read randomly is in a power function relationship with the photocurrent I photo of the diode D, namely:
  • the ideality factor is basically the same, that is, ⁇ 1 ⁇ 2 , so the output current ISD2 has a power function relationship with the light intensity P, namely:
  • the output current of the pixel circuit has a similar linear relationship with the light intensity. Therefore, the active pixel circuit has the characteristics of random reading, high sensitivity, and wide dynamic range.
  • This embodiment discloses another active pixel circuit that can be read randomly, as shown in FIG. 4, including: a photodiode D, a single-gate thin film transistor TFT1, a double-gate thin film transistor TFT2, a first power supply V DD , a second The power supply V BG , the first power supply V DD is connected to the drain of the single-gate thin film transistor TFT1 and the drain of the double-gate thin film transistor TFT2, and the drain of the single-gate thin film transistor TFT1 is connected to the gate of the single-gate thin film transistor TFT1.
  • the source of the thin film transistor TFT1 is connected to the cathode of the diode D, the anode of the photodiode D is grounded, the source of the single gate thin film transistor TFT1 is connected to the gate of the double gate thin film transistor TFT2, and the double gate thin film transistor TFT2 is connected to the second power supply V BG Connected, the source of the double-gate thin film transistor TFT2 is the signal output terminal, the first power source V DD is used to provide the working voltage for the single-gate thin film transistor TFT1, and the second power source V BG is used to control the double-gate thin film transistor TFT2.
  • the photodiode D is a photodiode with an n-i-p structure.
  • the active layer material of the single-gate thin film transistor TFT1 and the active layer material of the double-gate thin film transistor TFT2 are both amorphous silicon, indium gallium zinc oxide, n-type organic semiconductor, n-type low-temperature polysilicon, etc.
  • a type of material, the dual-gate thin film transistor TFT2 is used to replace the source follower and selection switch in Log APS, which reduces the use of internal components of the pixel, improves the aperture ratio of the pixel and simplifies the production process.
  • the photodiode D When the sensor pixel circuit is in the working state, the photodiode D needs to be reverse biased to make it light-sensitive, so the first power supply V DD and the second power supply V BG are both externally biased ports; -Si, IGZO, n-type organic semiconductors and n-type low-temperature polysilicon are all n-type materials and generally require positive voltage to be driven. Therefore, the photodiode D with nip structure is adopted, that is, the cathode is used as the external bias port and the anode is grounded.
  • V DD When the sensor pixel circuit is working, V DD is forward biased, and the photodiode D is in a reverse biased state.
  • the photo-generated carriers in the photodiode D generate electron-hole pairs due to the external bias.
  • the cathode and anode move, and the photocurrent and total current flowing through the photodiode D are the same as equations (1) and (2).
  • the gate-drain voltage, sub-threshold region current, and source-drain voltage of the single-gate thin film transistor TFT1 are the same as equations (3), (4), and (6), respectively.
  • V TG V DD -V DS1 (17)
  • the threshold voltage V T2 of the double-gate thin film transistor TFT2 can be obtained. Adjusting the size of V DG to make the double-gate thin film transistor TFT2 work in the sub-threshold region, the output current I DS2 of the sub-threshold region of the double-gate thin film transistor TFT2 can be obtained as:
  • S 2 is the sub-threshold swing of the double-gate thin film transistor TFT2. when That is, when V DS2 >>0.0258V (at room temperature), formula (18) can be simplified as:
  • the final output current I DS2 of the active pixel sensor circuit that can be read at random is in a power function relationship with the photocurrent I photo of the diode D, namely:
  • the sub-threshold swing is basically the same, that is, S 1 ⁇ S 2 , so the output current I DS2 has a power function relationship with the light intensity P, namely:
  • the active layer material is an n-type double-gate thin film transistor
  • the control coefficient ⁇ of the top gate voltage to the threshold voltage is -0.9 ⁇ -2
  • the output current of the pixel circuit has a linear relationship with the light intensity.
  • the active pixel image sensor designed in this embodiment retains the characteristic of being able to be read randomly, and because the output of the sensor has a linear relationship with the light intensity, the output current varies with the light intensity under weak light intensity. Strong changes are more obvious, so it has higher sensitivity and wider dynamic response range.
  • This embodiment discloses another active pixel circuit that can be read randomly.
  • the difference from the third embodiment is that the photodiode D is a diode with a pin structure, and the anode of the photodiode D is connected to a single gate film.
  • the source of the transistor TFT1 is connected, the cathode of the photodiode D is grounded, the first power supply V DD is used to provide the working voltage for the single-gate thin film transistor TFT1, and the second power supply V BG is used to provide the working voltage for the double-gate thin film transistor TFT2.
  • the active layer material of the single-gate thin film transistor TFT1 and the active layer material of the double-gate thin film transistor TFT2 are both p-type low-temperature polysilicon or p-type organic semiconductor and other p-type materials, using double-gate thin film
  • the transistor TFT2 replaces the source follower and selection switch in the Log APS, reduces the use of internal components of the pixel, increases the aperture ratio of the pixel and simplifies the production process.
  • the first power supply VDD When the sensor pixel circuit is in working state, because it is composed of a pin-type photodiode and a p-type thin film device, the first power supply VDD must be applied with a negative bias to make the thin film transistor in working state and the photodiode D is in the reverse direction Bias state.
  • the total current flowing through the photodiode D is the same as equation (11).
  • the gate voltage and source-drain voltage of the single-gate thin film transistor TFT1 are also the same as formula (3), that is, the gate voltage is equal to the source-drain voltage.
  • the gate-drain voltage, sub-threshold region current, and source-drain voltage of the single-gate thin film transistor TFT1 are the same as equations (3), (4), and (14), respectively.
  • V TG V DD -V DS1 (20)
  • the threshold voltage V T2 of the double-gate thin film transistor TFT2 can be obtained. Adjusting the size of V DG to make the double-gate thin film transistor TFT2 work in the sub-threshold region, the output current I SD2 of the sub-threshold region of the double-gate thin film transistor TFT2 can be obtained as:
  • formula (21) can be simplified to:
  • the final output current I SD2 of the active pixel sensor circuit that can be read randomly is in a power function relationship with the photocurrent I photo of the diode D, namely:
  • the ideality factor is basically the same, that is, ⁇ 1 ⁇ 2 , so the output current ISD2 has a power function relationship with the light intensity P, namely:
  • the output current of the pixel circuit has a similar linear relationship with the light intensity. Therefore, the active pixel circuit has the characteristics of random reading, high sensitivity, and wide dynamic range.
  • This embodiment discloses a driving method of an active pixel circuit that can be read randomly, which is applicable to Embodiment 1 to Embodiment 4, and includes the following steps:
  • the active pixel circuit that can be read randomly When the active pixel circuit that can be read randomly is in working state, apply voltage to the photodiode to make the photodiode in a reverse biased state, and generate photocurrent under illumination, so that the first transistor and the second transistor work in the sub-threshold region , So that the output current of the active pixel circuit that can be read randomly is in a power function relationship with the photocurrent of the photodiode, so that the output signal and light intensity of the active pixel sensor circuit that can be read randomly are in a linear relationship, so the sensitivity and The dynamic response range can be optimized at the same time.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Solid State Image Pick-Up Elements (AREA)

Abstract

本发明公开了一种可随机读取的有源像素电路及其驱动方法，该有源像素电路包括：光电二极管、第一晶体管、第二晶体管、第一电源以及第二电源；所述第一电源与所述第二晶体管的漏极连接且通过所述二极管与所述第一晶体管的漏极连接，所述第一晶体管的漏极与所述第一晶体管的栅极以及所述第二晶体管的顶栅连接，所述第一晶体管的源极接地，所述第二晶体管的底栅与所述第二电源连接，所述第二晶体管的源极为信号输出端。本发明使可随机读取有源像素传感器电路的输出电流与二极管的光电流呈幂函数关系，而达到电路的输出信号和光强呈类线性关系，因此传感器的灵敏度和动态响应范围能同时得到优化。

Description

一种可随机读取的有源像素电路及其驱动方法 技术领域
本发明属于电路技术领域，具体涉及一种可随机读取的有源像素电路及其驱动方法。
背景技术
传统的有源像素电路通常包含三个晶体管(重置开关晶体管Trst、源极跟随器Tsf和选择开关晶体管Tsel)和一个光电二极管。如果将重置开关晶体管Trst的栅极和漏极短接可以形成如图1的对数有源像素传感器(Logarithmic Active Pixel Sensor,Log.APS)。与普通的有源像素电路相比，Log.APS的输出信号随着光强的变化呈对数变化，因此具有更宽的动态响应范围，一般至少100dB以上。另外，Log.APS不需要对传感器进行重置，电路简单，像素填充因子更大，操作也更快，更简单。同时，Log.APS中每个像素是独立工作的且光电转换过程中不需要对光生电荷进行时间积分，所以在空间上和时间上可随机进行读取，空间上的随机读取性允许独立地读取和处理重要信号，使得传感器更加智能化，而时间上的可随机读取性则使得信号能更快速地被读取出来并进行处理，因此空间和时间的可随机读取性能使有效信号的读取速度更快。
但是，Log.APS像素内部的器件连接方式却使得输出信号随着光照强度的增加而减小，使得后端的信号读出和处理电路需要进行重新设计。而且，正是由于Log.APS输出与输入呈对数关系，所以传感器在弱光下的灵敏度比较低。最后，采用了三个晶体管的有源像素的设计也使得像素尺寸也难以进一步降低，进而影响到像素的灵敏度。
发明内容
为了克服上述技术缺陷，本发明提供了一种可随机读取有源像素传感器电路，其能提高可随机读取有源像素传感器电路的灵敏度和动态范围。
为了解决上述问题，本发明按以下技术方案予以实现的：
一种可随机读取的有源像素电路，包括：光电二极管、第一晶体管、第二晶体管、第一电源以及第二电源；
所述第一电源与所述第二晶体管的漏极连接且通过所述二极管与所述第一晶体管的漏极连接，所述第一晶体管的漏极与所述第一晶体管的栅极以及所述第二晶体管的顶栅连接，所述第一晶体管的源极接地，所述第二晶体管的底栅与所述第二电源连接，所述第二晶体管的源极为信号输出端。
与现有技术相比，本电路的有益效果是：在Log.APS的基础上将源极跟随器和选择开关管这两个晶体管替换成一个晶体管，使传感器电路保留了Log.APS的随机读取性能的同时，又能让输出和输入呈类线性的关系，使得传感器的弱光照下的灵敏度和动态范围得到提高，并且像素中有源器件数量的减少，也提高了像素的开口率和填充因子。
作为本发明的进一步改进，所述第一晶体管为单栅晶体管，所述第二晶体管为双栅晶体管。
作为本发明的进一步改进，所述光电二极管为n-i-p结构的二极管，所述第一晶体管和所述第二晶体管均为n型半导体器件，所述第一电源与所述光电二极管的阴极连接，所述光电二极管的阳极与所述第一晶体管的漏极连接。
作为本发明的进一步改进，所述光电二极管为p-i-n结构的二极管，所述第一晶体管、所述第二晶体管为p型半导体器件，所述第一电源与所述光电二极管的阳极连接，所述光电二极管的阴极与所述第一晶体管的漏极连接。
同时，本发明还提供了另一种可随机读取的有源像素电路，包括：光电二极管、第一晶体管、第二晶体管、第一电源以及第二电源；
所述第一电源与所述第一晶体管的漏极以及所述第二晶体管的漏极连接，所述第一晶体管的漏极与所述第一晶体管的栅极连接，所述第一晶体管的源极与所述第二晶体管的顶栅连接且通过所述光电二极管接地，所述第二晶体管的底栅与所述第二电源连接，所述第二晶体管的源极为信号输出端。
作为本发明的进一步改进，所述第一晶体管为单栅薄膜晶体管，所述第二晶体管为双栅薄膜晶体管。
作为本发明的进一步改进，所述光电二极管为n-i-p结构的二极管，所述第一晶体管、所述第二晶体管均为n型半导体器件，所述二极管的阴极与所述第一晶体管的源极、所述第二晶体管的顶栅连接，所述二极管的阳极接地。
作为本发明的进一步改进，所述光电二极管为p-i-n结构的光电二极管，所述第一晶体管、所述第二晶体管均为p型半导体器件，所述光电二极管的阳极与所述第一晶体管的源极、所述第二晶体管的顶栅连接，所述光电二极管的阴极接地。
本发明还提供了一种如上述的可随机读取的有源像素电路的驱动方法，包括如下步骤：
在所述可随机读取的有源像素电路处于工作状态时，向所述光电二极管施加电压，使所述光电二极管处于反偏状态，并在光照下产生光电流，使所述第一晶体管、所述第二晶体管工作在亚阈值区，从而使所述可随机读取的有源像素电路的输出电流与所述光电二极管的光电流呈幂函数关系。
与现有技术相比，本方法的有益效果是：使可随机读取的有源像素电路的输出电流与二极管的光电流呈幂函数关系，而达到传感器电路的输出信号和光强呈类线性关系，形成对数-指数像素电路，因此传感器的灵敏度和动态响应范围能同时得到优化。
附图说明
下面结合附图对本发明的具体实施方式作进一步详细的说明，其中：
图1为传统的对数有源像素电路的示意图；
图2为实施例一所述有源像素电路的示意图；
图3为实施例二所述有源像素电路的示意图；
图4为实施例三所述有源像素电路的示意图；
图5为实施例四所述有源像素电路的示意图。
具体实施方式
以下结合附图对本发明的优选实施例进行说明，应当理解，此处所描述的优选实施例仅用于说明和解释本发明，并不用于限定本发明。
实施例一
本实施例公开了一种可随机读取有源像素电路，如图2所示，包括：光电二极管D、单栅薄膜晶体管TFT1、双栅薄膜晶体管TFT2，第一电源V DD与双栅薄膜晶体管TFT2的漏极连接，且光电二极管D的阳极与单栅薄膜晶体管TFT1的漏极连接，光电二极管D的阴极与第一电源V DD连接，单栅薄膜晶体管TFT1的漏极与单栅薄膜晶体管TFT1的栅极以及双栅薄膜晶体管TFT2的顶栅连接，单栅薄膜晶体管TFT1的源极接地，双栅薄膜晶体管TFT2的底栅与第二电源V BG连接，双栅薄膜晶体管TFT2的源极为信号输出端，第一电源V DD用于为光电二极管D提供反向偏置电压、第二电源V BG用于操控双栅薄膜晶体管。
在上述实施例中，光电二极管D为n-i-p结构的光电二极管，其可以采用非晶硅二极管或有机二极管等多种二极管或类似光电探测器。
在上述实施例中，单栅薄膜晶体管TFT1的有源层材料、双栅薄膜晶体管TFT2的有源层材料均为非晶硅、铟镓锌氧化物、n型有机半导体和n型低温多晶硅等n型材料的一种，用双栅薄膜晶体管TFT2代替了Log APS中的源极跟随器和选择开关管，减少像素内部器件的数量，提高像素的开口率和填充因子。
本实施例对电路进行改进，使像素在保持空间和时间上的可随机读取性的同时其输出与输入呈类线性正相关关系，方便后端信号读出和信号处理电路的设计。
接下来结合具体实施过程对本实施例做进一步解释，如下：
当传感器像素电路处于工作状态时，需将光电二极管D反向偏置，能使其进行感光，所以第一电源V DD、第二电源V BG均为外加偏压端口；而由于制作薄膜晶体管的a-Si、IGZO、n型有机半导体和n型低温多晶硅都是n型材料，一般需要施加正电压才能驱动，故采用n-i-p结构的光电二极管D，即阴极作为外偏压端口，阳极连接到TFT1的栅极。传感器像素电路工作时，V DD为正偏压，光电二极管D处于反向偏置状态，此时光电二极管D中的光生载流子由于外偏压的作用，产生电子-空穴对并且分别向阴极和阳极运动，形成光生电流I photo：
Figure PCTCN2020078925-appb-000001
其中，q为元电荷，η 0为二极管D的量子效率，P为光强，A PD为二极管D的感光面积，λ为波长，R为反射系数，α和t分别为二极管D有源层的吸收系数和厚度，h为普朗克常数，c为真空中的光速。故流过二极管D的总电流则为：
I PD＝I DS1＝I dark+I photo   (2)
I dark为暗态下二极管D处于反偏时的漏电流。
在单栅薄膜晶体管TFT1中，栅极与漏极短接，所以栅极电压V GS与源漏极电压V DS1相等：
V GS＝V DS1   (3)
使单栅薄膜晶体管TFT1工作在亚阈值区，则根据薄膜晶体管亚阈值区电流公式，可得TFT1的源漏电流I DS1为：
Figure PCTCN2020078925-appb-000002
其中，I D01为V GS＝V T1且V DS1＞＞kT/q时,单栅薄膜晶体管TFT1的输出电流，V T1为单栅薄膜晶体管TFT1的阈值电压
Figure PCTCN2020078925-appb-000003
S 1为单栅薄膜晶体管TFT1的亚阈值摆幅，k为玻尔兹曼常数，T为温度。当
Figure PCTCN2020078925-appb-000004
即V DS1＞＞0.0258V(室温下)时，式(4)可简化为：
Figure PCTCN2020078925-appb-000005
将上式(5)进行变换，可得单栅薄膜晶体管TFT1源漏极电压V DS1为：
Figure PCTCN2020078925-appb-000006
又因为光电二极管D的阳极、单栅薄膜晶体管TFT1的栅极和漏端、双栅薄膜晶体管TFT2的顶栅这四个端口连接在一起，故有：
V TG＝V DS1  (7)
对于双栅薄膜晶体管TFT2，其阈值电压V T2可表示为：
V T2＝V TH0+γV TG  (8)
其中，V TH0为V TG＝0时TFT2的阈值电压，γ为第二栅电压对阈值电压的控制系数。
调节V DG的大小，使双栅薄膜晶体管TFT2工作于亚阈值区，则可得双栅薄膜晶体管TFT2的亚阈值区输出电流I DS2为：
Figure PCTCN2020078925-appb-000007
其中，I D02为V BG＝V T2且V DS2＞＞kT/q时,双栅薄膜晶体管TFT2的输出电流，
Figure PCTCN2020078925-appb-000008
S 2为双栅薄膜晶体管TFT2的亚阈值摆幅。当
Figure PCTCN2020078925-appb-000009
即V DS2＞＞0.0258V(室温下)时，式(9)可简化为：
Figure PCTCN2020078925-appb-000010
因此，该可随机读取有源像素传感器电路器最终的输出电流I DS2与二极管D的光电流I photo呈幂函数关系，即：
Figure PCTCN2020078925-appb-000011
对于相同有源材料、相同制程工艺的薄膜晶体管，亚阈值摆幅基本不变，即S 1≈S 2，所以可得输出电流I DS2与光强P呈幂函数关系，即：
I DS2∝P -γ
若n型双栅薄膜晶体管的顶栅电压对阈值电压的控制系数γ为-0.9～-2，则有源像素电路的输出电流与光强呈类线性关系。因此，对于一般的对数有源像素传感器来说，本实施例设计的基于n型半导体器件的有源像素电路保留了可随机读取的特性，并且因为该像素电路的输出与光强呈类线性关系，在弱光强下，输出电流随光强的变化更明显，因此具有更高的灵敏度和更宽的动态响应范围。
实施例二
本实施例公开了另一种可随机读取有源像素电路，如图3所示，其与实施例一的区别在于：光电二极管D为p-i-n结构的光电二极管，第一电源V DD与光电二极管D的阳极连接，光电二极管D的阴极与单栅薄膜晶体管TFT1的漏极连接，第一电源V DD用于为光电二极管D提供反向偏置电压、第二电源V BG为双栅薄膜晶体管TFT2的工作电压。
在上述实施例中，单栅薄膜晶体管TFT1的有源层材料、双栅薄膜晶体管TFT2的有源层材料均为p型低温多晶硅或p型有机半导体等p型材料的一种，用双栅薄膜晶体管TFT2代替了Log APS中的源极跟随器和选择开关管，减少像素内部器件的使用，提高像素的开口率并且简化了生产工艺。
接下来结合具体实施过程对本实施例做进一步解释，如下：
当传感器像素电路处于工作状态时，因为是由p-i-n型二极管和p型薄膜器件组成的，故第一电源VDD必须施加负偏压，才能让光电二极管D处于反向偏置状态并且薄膜晶体管处于工作状态。流过光电二极管D的总电流为：
I PD＝I SD1＝I dark+I photo   (11)
单栅薄膜晶体管TFT1的栅极电压和源漏极电压也与式(3)相同，即栅极电压与源漏极电压相等。由p型薄膜晶体管亚阈值区的电流公式可得TFT1的亚阈值电流I SD1为：
Figure PCTCN2020078925-appb-000012
其中，
Figure PCTCN2020078925-appb-000013
β 1为单栅薄膜晶体管TFT1的理想参数。当V DS1＜＜-V sth1时，式(12)可简化为：
Figure PCTCN2020078925-appb-000014
将式(13)进行变换，可得单栅薄膜晶体管TFT1源漏极电压V DS1为：
Figure PCTCN2020078925-appb-000015
由公式(7)(8)可得双栅薄膜晶体管TFT2的顶栅电压V TG和阈值电压V T2。同样地，调节V DG的大小，使双栅薄膜晶体管TFT2工作于亚阈值区，则可得双栅薄膜晶体管TFT2的亚阈值区输出电流I SD2为：
Figure PCTCN2020078925-appb-000016
当V DS2＜＜-V sth2，式(14)可化简为：
Figure PCTCN2020078925-appb-000017
因此，该可随机读取有源像素传感器电路最终的输出电流I SD2与二极管D的光电流I photo呈幂函数关系，即：
Figure PCTCN2020078925-appb-000018
对于相同有源材料、相同制程工艺的薄膜晶体管，理想因子基本不变，即β 1≈β 2，所以可得输出电流ISD2与光强P呈幂函数关系，即：
I SD2∝P -γ
若有源层材料为p型材料的双栅薄膜晶体管的顶栅电压对阈值电压的控制系数γ为-0.9～-2，则像素电路的输出电流与光强呈类线性关系。因此，该有源像素电路具有可随机读取、高灵敏度、宽动态范围的特点。
实施例三
本实施例公开了另一种可随机读取的有源像素电路，如图4所示，包括：光电二极管D、单栅薄膜晶体管TFT1、双栅薄膜晶体管TFT2、第一电源V DD、第二电源V BG，第一电源V DD与单栅薄膜晶体管TFT1的漏极以及双栅薄膜晶体管TFT2的漏极连接，单栅薄膜晶体管TFT1的漏极与单栅薄膜晶体管TFT1的栅极连接，单栅薄膜晶体管TFT1的源极与二极管D的阴极连接，光电二极管D的阳极接地，单栅薄膜晶体管TFT1的源极与双栅薄膜晶体管TFT2的栅极连接，双栅薄膜晶体管TFT2与第二电源V BG连接，双栅薄膜晶体管TFT2的源极为信号输出端，第一电源V DD用于为单栅薄膜晶体管TFT1提供工作电压、第二电源V BG用于操控双栅薄膜晶体管TFT2。
在上述实施例中，光电二极管D为n-i-p结构的光电二极管。
在上述实施例中，单栅薄膜晶体管TFT1的有源层材料、双栅薄膜晶体管TFT2的有源层材料均为非晶硅、铟镓锌氧化物、n型有机半导体和n型低温多晶硅等n型材料的一种，用双栅薄膜晶体管TFT2代替了Log APS中的源极跟随器和选择开关管，减少像素内部器件的使用，提高像素的开口率并且简化了生产工艺。
接下来结合具体实施过程对本实施例做进一步解释，如下：
当传感器像素电路处于工作状态时，需将光电二极管D反向偏置，使其进行感光，所以第一电源V DD、第二电源V BG均为外加偏压端口；而由于制作薄膜晶体管的a-Si、IGZO、n型有机半导体和n型低温多晶硅都是n型材料，一般需要施加正电压才能驱动，故采用n-i-p结构的光电二极管D，即阴极作为外偏压端口，阳极接地。传感器像素电路工作时，V DD为正偏压，光电二极管D处于反向偏置状态，此时光电二极管D中的光生载流子由于外偏压的作用，产生电子-空穴对并且分别向阴极和阳极运动，流过光电二极管D的光电流和总电流与式(1)(2)相同。单栅薄膜晶体管TFT1的栅漏电压、亚阈值区电流以及源漏电压则分别与式(3)、式(4)、式(6)相同。
因为光电二极管D的阴极、单栅薄膜晶体管TFT1的源极、双栅薄膜晶体管TFT2的顶栅这三个端口连接在一起，故有：
V TG＝V DD-V DS1  (17)
由公式(8)可得双栅薄膜晶体管TFT2的阈值电压V T2。调节V DG的大小，使双栅薄膜晶体管TFT2工作于亚阈值区，则可得双栅薄膜晶体管TFT2的亚阈值区输出电流I DS2为：
Figure PCTCN2020078925-appb-000019
其中，I D02为V BG＝V T2且V DS2＞＞kT/q时,双栅薄膜晶体管TFT2的输出电流，
Figure PCTCN2020078925-appb-000020
S 2为双栅薄膜晶体管TFT2的亚阈值摆幅。当
Figure PCTCN2020078925-appb-000021
即V DS2＞＞0.0258V(室温下)时，式(18)可简化为：
Figure PCTCN2020078925-appb-000022
因此，该可随机读取有源像素传感器电路器最终的输出电流I DS2与二极管D的光电流I photo呈幂函数关系，即：
Figure PCTCN2020078925-appb-000023
对于相同有源材料、相同制程工艺的薄膜晶体管，亚阈值摆幅基本不变，即S 1≈S 2，所以可得输出电流I DS2与光强P呈幂函数关系，即：
I DS2∝P γ
若有源层材料为n型的双栅薄膜晶体管的顶栅电压对阈值电压的控制系数γ为-0.9～-2，则 像素电路的输出电流与光强呈类线性关系，对于一般的对数有源像素传感器来说，本实施例设计的有源像素图像传感器保留了可随机读取的特性，并且因为该传感器的输出与光强呈类线性关系，在弱光强下，输出电流随光强的变化更明显，因此具有更高的灵敏度和更宽的动态响应范围。
实施例四
本实施例公开了另一种可随机读取有源像素电路，如图5所示，其与实施例三的区别在于：光电二极管D为p-i-n结构的二极管，光电二极管D的阳极与单栅薄膜晶体管TFT1的源极连接，光电二极管D的阴极接地，第一电源V DD用于为单栅薄膜晶体管TFT1提供工作电压，第二电源V BG为双栅薄膜晶体管TFT2提供工作电压。
在上述实施例中，单栅薄膜晶体管TFT1的有源层材料、双栅薄膜晶体管TFT2的有源层材料均为p型低温多晶硅或p型有机半导体等p型材料的一种，用双栅薄膜晶体管TFT2代替了Log APS中的源极跟随器和选择开关管，减少像素内部器件的使用，提高像素的开口率并且简化了生产工艺。
接下来结合具体实施过程对本实施例做进一步解释，如下：
当传感器像素电路处于工作状态时，因为是由p-i-n型的光电二极管和p型薄膜器件组成的，故第一电源VDD必须施加负偏压，才能让薄膜晶体管处于工作状态并且光电二极管D处于反向偏置状态。流过光电二极管D的总电流与式(11)相同。单栅薄膜晶体管TFT1的栅极电压和源漏极电压也与式(3)相同，即栅极电压与源漏极电压相等。单栅薄膜晶体管TFT1的栅漏电压、亚阈值区电流以及源漏电压则分别与式(3)、式(4)、式(14)相同。
因为光电二极管D的阳极、单栅薄膜晶体管TFT1的源极、双栅薄膜晶体管TFT2的顶栅这三个端口连接在一起，故有：
V TG＝V DD-V DS1  (20)
由公式(8)可得双栅薄膜晶体管TFT2的阈值电压V T2。调节V DG的大小，使双栅薄膜晶体管TFT2工作于亚阈值区，则可得双栅薄膜晶体管TFT2的亚阈值区输出电流I SD2为：
Figure PCTCN2020078925-appb-000024
当V DS2＜＜-V sth2，式(21)可化简为：
Figure PCTCN2020078925-appb-000025
因此，该可随机读取有源像素传感器电路最终的输出电流I SD2与二极管D的光电流I photo呈幂函数关系，即：
Figure PCTCN2020078925-appb-000026
对于相同有源材料、相同制程工艺的薄膜晶体管，理想因子基本不变，即β 1≈β 2，所以可得输出电流ISD2与光强P呈幂函数关系，即：
I SD2∝P γ
若有源层材料为p型材料的双栅薄膜晶体管的顶栅电压对阈值电压的控制系数γ为-0.9～-2，则像素电路的输出电流与光强呈类线性关系。因此，该有源像素电路具有可随机读取、高灵敏度、宽动态范围的特点。
实施例五
本实施例公开了一种可随机读取的有源像素电路的驱动方法，其适用于实施例一-实施例四，包括如下步骤：
在可随机读取的有源像素电路处于工作状态时，向光电二极管施加电压，使光电二极管处于反偏状态，并在光照下产生光电流，使第一晶体管、第二晶体管工作在亚阈值区，从而使可随机读取的有源像素电路的输出电流与光电二极管的光电流呈幂函数关系，从而使可随机读取有源像素传感器电路的输出信号和光强度呈类线性关系，因此灵敏度和动态响应范围能同时得到优化。
以上所述，仅是本发明的较佳实施例而已，并非对本发明作任何形式上的限制，故凡是未脱离本发明技术方案内容，依据本发明的技术实质对以上实施例所作的任何修改、等同变化与修饰,均仍属于本发明技术方案的范围内。

Claims (9)

  1. 一种可随机读取的有源像素电路，其特征在于，包括：光电二极管、第一晶体管、第二晶体管、第一电源以及第二电源；
    所述第一电源与所述第二晶体管的漏极连接且通过所述二极管与所述第一晶体管的漏极连接，所述第一晶体管的漏极与所述第一晶体管的栅极以及所述第二晶体管的顶栅连接，所述第一晶体管的源极接地，所述第二晶体管的底栅与所述第二电源连接，所述第二晶体管的源极为信号输出端。
  2. 根据权利要求1所述的有源像素电路，其特征在于，所述第一晶体管为单栅晶体管，所述第二晶体管为双栅晶体管。
  3. 根据权利要求2所述的有源像素电路，其特征在于，所述光电二极管为n-i-p结构的光电二极管，所述第一晶体管和所述第二晶体管均为n型半导体器件，所述第一电源与所述光电二极管的阴极连接，所述光电二极管的阳极与所述第一晶体管的漏极连接。
  4. 根据权利要求2所述的有源像素电路，其特征在于，所述光电二极管为p-i-n结构的光电二极管，所述第一晶体管、所述第二晶体管均为p型半导体器件，所述第一电源与所述光电二极管的阳极连接，所述光电二极管的阴极与所述第一晶体管的漏极连接。
  5. 一种可随机读取的有源像素电路，其特征在于，包括：光电二极管、第一晶体管、第二晶体管、第一电源以及第二电源；
    所述第一电源与所述第一晶体管的漏极以及所述第二晶体管的漏极连接，所述第一晶体管的漏极与所述第一晶体管的栅极连接，所述第一晶体管的源极与所述第二晶体管的顶栅连接且通过所述光电二极管接地，所述第二晶体管的底栅与所述第二电源连接，所述第二晶体管的源极为信号输出端。
  6. 根据权利要求5所述的有源像素电路，其特征在于，所述第一晶体管为单栅薄膜晶体管，所述第二晶体管为双栅薄膜晶体管。
  7. 根据权利要求6所述的有源像素电路，其特征在于，所述光电二极管为n-i-p结构的光电二极管，所述第一晶体管、所述第二晶体管均为n型半导体器件，所述光电二极管的阴极与所述第一晶体管的源极、所述第二晶体管的顶栅连接，所述二极管的阳极接地。
  8. 根据权利要求6所述的有源电路，其特征在于，所述光电二极管为p-i-n结构的光电二极管，所述第一晶体管、所述第二晶体管均为p型半导体器件，所述光电二极管的阳极与所述第一晶体管的源极、所述第二晶体管的顶栅连接，所述二极管的阴极接地。
  9. 一种如权利要求1-8任一项所述可随机读取的有源像素电路的驱动方法，其特征在于，包括如下步骤：
    在所述可随机读取的有源像素电路处于工作状态时，向所述光电二极管施加电压，使所 述光电二极管处于反偏状态，并在光照下产生光电流，使所述第一晶体管、所述第二晶体管工作在亚阈值区，从而使所述可随机读取的有源像素电路的输出电流与所述光电二极管的光电流呈幂函数关系。
PCT/CN2020/078925 2019-12-27 2020-03-12 一种可随机读取的有源像素电路及其驱动方法 WO2021128595A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201911378964.9 2019-12-27
CN201911378964.9A CN111083399A (zh) 2019-12-27 2019-12-27 一种可随机读取的有源像素电路及其驱动方法

Publications (1)

Publication Number Publication Date
WO2021128595A1 true WO2021128595A1 (zh) 2021-07-01

Family

ID=70318684

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/078925 WO2021128595A1 (zh) 2019-12-27 2020-03-12 一种可随机读取的有源像素电路及其驱动方法

Country Status (2)

Country Link
CN (1) CN111083399A (zh)
WO (1) WO2021128595A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114046881A (zh) * 2021-11-15 2022-02-15 深圳知微创新技术有限公司 一种基于薄膜晶体管的高灵敏度颜色传感器

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4084468A1 (en) * 2021-04-29 2022-11-02 Imec VZW An active thin-film charge sensor element

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080018766A1 (en) * 2006-07-18 2008-01-24 Konica Minolta Holdings, Inc. Solid state image sensing device
CN101210845A (zh) * 2006-12-27 2008-07-02 株式会社半导体能源研究所 半导体装置以及使用其的电子设备
CN101556962A (zh) * 2008-04-11 2009-10-14 三星电子株式会社 包括具有两个栅极的感应晶体管的图像传感器及操作方法
CN101742131A (zh) * 2008-11-25 2010-06-16 上海华虹Nec电子有限公司 Cmos图像传感器的光电转换器
CN110460786A (zh) * 2019-08-09 2019-11-15 京东方科技集团股份有限公司 像素感应电路、第一偏置电压确定方法、电子设备

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080018766A1 (en) * 2006-07-18 2008-01-24 Konica Minolta Holdings, Inc. Solid state image sensing device
CN101210845A (zh) * 2006-12-27 2008-07-02 株式会社半导体能源研究所 半导体装置以及使用其的电子设备
CN101556962A (zh) * 2008-04-11 2009-10-14 三星电子株式会社 包括具有两个栅极的感应晶体管的图像传感器及操作方法
CN101742131A (zh) * 2008-11-25 2010-06-16 上海华虹Nec电子有限公司 Cmos图像传感器的光电转换器
CN110460786A (zh) * 2019-08-09 2019-11-15 京东方科技集团股份有限公司 像素感应电路、第一偏置电压确定方法、电子设备

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114046881A (zh) * 2021-11-15 2022-02-15 深圳知微创新技术有限公司 一种基于薄膜晶体管的高灵敏度颜色传感器
CN114046881B (zh) * 2021-11-15 2024-05-28 深圳知微创新技术有限公司 一种基于薄膜晶体管的高灵敏度颜色传感器

Also Published As

Publication number Publication date
CN111083399A (zh) 2020-04-28

Similar Documents

Publication Publication Date Title
US11848340B2 (en) Imaging device and electronic device
US9397282B2 (en) Active matrix light emitting diode array and projector display comprising it
US20050253132A1 (en) Photodetector circuits
US20220366663A1 (en) Image Detection Module and Information Management System
US20140159129A1 (en) Near-infrared-visible light adjustable image sensor
US9391103B2 (en) Image pickup element and image pickup device
WO2021128595A1 (zh) 一种可随机读取的有源像素电路及其驱动方法
JPS617663A (ja) デイプレツシヨン型薄膜半導体光検知器
CN110945861B (zh) 显示系统及显示系统的工作方法
KR20190059667A (ko) 아발란치 광검출기 및 이를 포함하는 이미지 센서
US9401383B2 (en) Photoconductive element for radiation detection in a radiography imaging system
KR20160010317A (ko) 반도체 장치, 촬상 장치, 및 전자 기기
JPS6033342B2 (ja) 固体撮像装置
US9773824B2 (en) Active matrix light emitting diode array and projector display comprising it
TW201417254A (zh) 寬動態範圍像素單元、其製造方法及其構成的圖像感測器
Gautam et al. Analytical model of double gate MOSFET for high sensitivity low power photosensor
CN211378129U (zh) 一种可随机读取的有源像素电路
WO2022095474A1 (zh) 一种像素单元和像素单元的信号处理方法
CN102820313B (zh) Cmos图像传感器
WO2023116035A1 (zh) 感光电路结构和光学器件
CN113454795A (zh) 用于显示器下指纹和手势传感器的具有半导体活性层的光检测器
US20230109524A1 (en) Imaging device and electronic device
WO2021189619A1 (zh) 光电传感器、可随机读取有源像素电路、图像传感器和相机装置
US11943554B2 (en) Imaging device operated by switching between product-sum operation
CN105100651B (zh) 图像传感器及降低图像传感器噪声的方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20905813

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20905813

Country of ref document: EP

Kind code of ref document: A1

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 02/02/2023)

122 Ep: pct application non-entry in european phase

Ref document number: 20905813

Country of ref document: EP

Kind code of ref document: A1