WO2015085702A1 - 像素电路及其驱动方法、显示装置 - Google Patents
像素电路及其驱动方法、显示装置 Download PDFInfo
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- WO2015085702A1 WO2015085702A1 PCT/CN2014/076485 CN2014076485W WO2015085702A1 WO 2015085702 A1 WO2015085702 A1 WO 2015085702A1 CN 2014076485 W CN2014076485 W CN 2014076485W WO 2015085702 A1 WO2015085702 A1 WO 2015085702A1
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Classifications
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- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
- G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
- G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
- G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
- G09G3/3225—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
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- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
- G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
- G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
- G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
- G09G3/3225—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
- G09G3/3233—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the current through the light-emitting element
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- G09G2300/0809—Several active elements per pixel in active matrix panels
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- G09G2300/0861—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
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- G09G2310/00—Command of the display device
- G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
- G09G2310/0243—Details of the generation of driving signals
- G09G2310/0251—Precharge or discharge of pixel before applying new pixel voltage
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- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
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- G09G2320/02—Improving the quality of display appearance
- G09G2320/0233—Improving the luminance or brightness uniformity across the screen
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- G09G2320/00—Control of display operating conditions
- G09G2320/04—Maintaining the quality of display appearance
- G09G2320/043—Preventing or counteracting the effects of ageing
- G09G2320/045—Compensation of drifts in the characteristics of light emitting or modulating elements
Definitions
- the present disclosure relates to the field of display technologies, and in particular, to a pixel circuit, a driving method thereof, and a display device. Background technique
- OLED Organic Light Emitting Diode
- PMOLED passive matrix driving OLED
- AMOLED active matrix driving OLED
- Conventional PMOLEDs generally require a reduction in the driving time of a single pixel as the size of the display device increases, and thus it is necessary to increase the transient current, resulting in a significant increase in power consumption.
- AMOLED technology each OLED scans the input current progressively through a Thin Film Transistor (TFT) switching circuit, which can solve these problems well.
- TFT Thin Film Transistor
- the TFT switching circuit uses a low temperature polysilicon thin film transistor (LTPS TFT) or an oxide thin film transistor (Oxide TFT).
- LTPS TFTs and Oxide TFTs have higher mobility and more stable characteristics, and are more suitable for use in AMOLED displays.
- TFT switching circuits fabricated on large-area glass substrates often exhibit non-uniformities in electrical parameters such as threshold voltage and mobility, thereby making the threshold voltage of each TFT biased. Inconsistent shifts, which will result in current and brightness differences in the OLED display device and are perceived by the human eye.
- the long-term pressurization and high temperature also cause the threshold voltage of the TFT to drift. Due to the difference in display screens, the threshold value of the TFTs in the various parts of the panel is different, resulting in a difference in display brightness. Since this difference is related to the previously displayed image, it is often presented as an afterimage phenomenon. Summary of the invention
- a pixel circuit including: a first transistor, a second transistor, a third transistor, a storage capacitor, a parasitic capacitor, and a light emitting device;
- the first pole of the first transistor is connected to the first power signal end, and the second pole is connected to the first pole of the third transistor;
- the gate of the second transistor is connected to the first control signal end, the first pole is connected to the data signal end, and the second pole is connected to the gate of the first transistor;
- a gate of the third transistor is connected to the second control signal end, and a second pole is connected to one end of the light emitting device; one end of the storage capacitor is connected to the gate of the first transistor, and the other end is connected to the light emitting One end of the device; one end of the parasitic capacitance is connected to one end of the light emitting device, and the other end is connected to the other end of the light emitting device; the other end of the light emitting device is further connected to the second power signal end.
- a display device comprising the pixel circuit as described above.
- a pixel circuit driving method for driving a pixel circuit as described above including: turning on a first transistor, a second transistor, and a third transistor, and inputting a data signal input reset a signal, the first power signal terminal is input to the first voltage control light emitting device in a closed state; the first transistor, the second transistor, and the third transistor are kept turned on, and the first power signal terminal is input to the second voltage , such that one end of the light emitting device is precharged;
- the current of the tube and the third transistor drives the light emitting device to emit light.
- the pixel circuit, the driving method thereof and the display device provided by the embodiment of the invention can perform switching and charge and discharge control on the circuit through a plurality of transistors and capacitors, so that the current for driving the light emitting device through the transistor can be independent of the threshold voltage of the transistor. It compensates for the difference in current flowing through the light-emitting device due to the inconsistency or offset of the threshold voltage of the transistor, improves the uniformity of the brightness of the display device, and significantly improves the display effect.
- FIG. 1 is a schematic diagram of a connection structure of a pixel circuit according to an embodiment of the present invention
- FIG. 2 is a timing diagram of driving each signal line of the pixel circuit shown in FIG. 1
- FIG. 3 is a diagram showing a pixel circuit in a reset phase according to an embodiment of the present invention
- FIG. 4 is a schematic diagram of an equivalent circuit of a pixel circuit in a compensation stage according to an embodiment of the present invention
- FIG. 5 is a schematic diagram of an equivalent circuit of a pixel circuit in preparation for writing data according to an embodiment of the present invention
- FIG. 7 is a schematic diagram of an equivalent circuit of a pixel circuit before being ready to drive a light emitting device according to an embodiment of the present invention
- FIG. 8 is an equivalent circuit diagram of a pixel circuit in an illuminating phase according to an embodiment of the present invention
- FIG. 10 is a schematic flow chart of a pixel circuit driving method according to an embodiment of the present invention
- FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. It is apparent that the described embodiments are only a part of the embodiments of the invention, and not all of the embodiments.
- FIG. 1 is a schematic diagram of a connection structure of a pixel circuit according to an embodiment of the present invention.
- the pixel circuit includes: a first transistor T1, a second transistor ⁇ 2, a third transistor ⁇ 3, a storage capacitor C1, a parasitic capacitance C2, and a light emitting device L.
- the first electrode of the first transistor T1 is connected to the first power signal terminal ELVDD, and the second electrode thereof is connected to the first electrode of the third transistor T3.
- the gate of the second transistor T2 is connected to the first control signal terminal S1, the first pole thereof is connected to the data signal terminal DATA, and the second pole thereof is connected to the gate of the first transistor T1.
- the gate of the third transistor T3 is connected to the second control signal terminal S2, and the second electrode thereof is connected to one end of the light emitting device L.
- One end of the storage capacitor C1 is connected to the gate of the first transistor T1, and the other end thereof is connected to one end of the light emitting device L.
- One end of the parasitic capacitance C2 is connected to one end of the light emitting device L, and the other end thereof is connected to the other end of the light emitting device L.
- the other end of the light emitting device L is also connected to the second power signal terminal ELVSS.
- the light-emitting device L in the embodiment of the present invention may be a plurality of current-driven light-emitting devices including a light emitting diode (LED) or an organic light emitting diode (OLED).
- LED light emitting diode
- OLED organic light emitting diode
- switching and charging and discharging control of the circuit by a plurality of transistors and capacitors can make the current for driving the light emitting device through the transistor independent of the threshold voltage of the transistor, and compensate for the transistor due to
- the difference in current flowing through the light-emitting device caused by the inconsistent or offset of the threshold voltage improves the uniformity of the luminance of the display device and significantly improves the display effect.
- the pixel circuit of such a structure has a simple structure and a small number of transistors, the area of the light-shielding region covering the transistor can be reduced, and the aperture ratio of the display device can be effectively increased.
- the first transistor T1, the second transistor ⁇ 2, and the third transistor ⁇ 3 may each be a ⁇ -type transistor; or the first transistor T1, the second transistor ⁇ 2, and the third crystal Tube T3 can be a germanium transistor.
- FIG. 1 is a timing diagram of each signal line during the operation of the pixel circuit shown in FIG. 1.
- Pl, ⁇ 2, ⁇ 3, and ⁇ 4 are used in the figure to respectively indicate the reset phase, the compensation phase, the data writing phase, and the illuminating phase.
- the P1 phase is a reset phase, and the equivalent circuit of this phase is shown in FIG. 3.
- the first control signal terminal S 1 and the second control signal terminal S2 both input a high level
- the first power signal terminal ELVDD inputs a low level (Vss)
- the data signal terminal DATA inputs a low level reset signal.
- Vref Vref-Vth>Vss
- Vth is the threshold voltage of the T1 transistor.
- the first transistor T1, the second transistor ⁇ 2, and the third transistor ⁇ 3 are turned on, the anode voltage of the light-emitting device L is Vss, and the light-emitting device L is turned off.
- the P2 phase is the compensation phase, and the equivalent circuit of this phase is shown in Figure 4.
- the first control signal terminal S1, the second control signal terminal S2, and the first power signal terminal ELVDD are both input with a high level
- the data signal terminal DATA is input with a low level reset signal (Vref).
- the first transistor T1, the second transistor T2, and the third transistor T3 remain turned on, and the anode voltage of the light-emitting device L rises as the first transistor T1 is charged until the voltage is equal to Vref-Vth.
- the charge stored across the storage capacitor C1 is Vth.C ST , where C ST is the capacitance of the storage capacitor C1.
- the P3 phase is the data writing phase. Specifically, before preparing to write data, it is necessary to turn off the third transistor T3, and the equivalent circuit at this time is as shown in FIG.
- the gate voltage of the first transistor T1 is a reset signal Vref of a low level input from the data signal terminal DATA. At this time, the anode voltage of the light-emitting device L is Vref-Vth.
- the equivalent circuit is as shown in FIG. 6, wherein the first control signal terminal S1 and the first power signal terminal ELVDD are both input with a high level, and the second control signal terminal S2 is input with a low level.
- the signal terminal DATA inputs a high level data signal (Vdata).
- the P4 phase is the illuminating phase. Specifically, before the pixel circuit is ready to drive the light emitting device to emit light, the second transistor T2 needs to be turned off, and the equivalent circuit at this time is as shown in FIG. 7.
- the first power signal terminal EL VDD and the second control signal terminal S 2 are both input with a high level, and the first control signal terminal S 1 and the data signal terminal DATA are both input with a low level, so that the third transistor T3 Turning on, the equivalent circuit at this time is as shown in FIG. 8.
- the voltage Vgs between the gate and the source of the first transistor T1 is (la) (Vdata - Vref) + Vth.
- the current flowing through the first transistor T1, the third transistor T3, and the light emitting device L in the light emitting phase is:
- the current of the light-emitting device L is independent of the TFT threshold voltage and the voltage across the OLED, thereby effectively eliminating the influence of the threshold voltage non-uniformity and drift.
- the effect of the threshold voltage non-uniformity can be compensated for both the enhancement type and the depletion type TFT, and thus the applicability is wider.
- the structure uses a small number of TFTs and a simple control signal, which is suitable for high-resolution pixel design.
- the timing of each control signal may be opposite to the timing of the signal in FIG. 2 (ie, the phase difference is 180 degrees).
- the pixel circuit of the embodiment of the present invention may further include:
- the fourth transistor ⁇ 4, the fourth transistor ⁇ 4 may be disposed in the first pixel circuit of the column of pixel circuits.
- the gate of the fourth transistor T4 is connected to the control line EL, the first electrode of which is connected to the second electrode of the second transistor T2, and the second electrode of which is connected to the first power supply signal terminal ELVDD.
- each of the fourth transistors T4 can correspond to a column of pixel circuits. Controlling the control line EL to the first power supply signal terminal ELVDD through a fourth transistor T4 can further increase the reliability of the pixel circuit control without additionally adding a timing signal design.
- the fourth transistor T4 may be an N-type transistor or a P-type transistor.
- the N-type transistors provided in the embodiments of the present invention may each be an N-type enhancement type TFT or an N-type depletion type TFT.
- the first poles of the first transistor T1, the second transistor ⁇ 2, the third transistor ⁇ 3, and the fourth transistor ⁇ 4 may each be referred to as a drain, and the second pole may be referred to as a source.
- a column of pixel circuits as shown in FIG. 9 can also be driven by using the timing signal design as shown in FIG. 2. The difference is that the timing of the first power supply signal terminal ELVDD is now used as the timing of the control line EL input signal.
- the driving method can be divided into four stages.
- a pixel circuit of such a structure switching and charging and discharging control of the circuit by a plurality of transistors and capacitors can make the current for driving the light emitting device through the transistor independent of the threshold voltage of the transistor, compensating for the transistor due to The difference in current flowing through the light-emitting device caused by the inconsistency or offset of the threshold voltage improves the uniformity of the brightness of the display device and significantly improves the display effect.
- the pixel circuit of such a structure has a simple structure and a small number of transistors, the area of the light-shielding region covering the transistor can be reduced, and the aperture ratio of the display device can be effectively increased.
- the transistors are all described with an enhanced germanium TFT as an example.
- a depletion mode TFT can also be used.
- the threshold voltage Vth is a positive value
- the threshold voltage Vth is a negative value.
- the fourth transistor T4 may be an N-type transistor or a P-type transistor. The above description is made by taking an N-type transistor as an example. Of course, the fourth transistor T4 may also use a P-type transistor, and the fourth transistor.
- T4 is a P-type transistor, the timing of the control line EL may be opposite to the ELVDD timing of FIG.
- Embodiments of the present invention also provide a display device including an organic light emitting display, other displays, and the like.
- the display device includes any of the pixel circuits described above.
- the display device may include a plurality of pixel unit arrays, each of which includes any one of the pixel circuits as described above.
- a fourth transistor T4 corresponds to a column of pixel units.
- the display device of the embodiment of the present invention may be a display device having a current-driven light-emitting device including an LED display or an OLED display.
- the display device of the embodiment of the invention includes a pixel circuit, and the switching and charging and discharging control of the circuit through a plurality of transistors and capacitors can make the current for driving the light emitting device through the transistor independent of the threshold voltage of the transistor, thereby compensating for The difference in current flowing through the light-emitting device caused by the inconsistency or offset of the threshold voltage of the transistor improves the uniformity of the brightness of the display device, and significantly improves the display effect.
- FIG. 10 is a schematic flow chart of a pixel circuit driving method according to an embodiment of the present invention.
- the pixel circuit driving method of the embodiment of the present invention can be applied to the pixel circuit provided in the foregoing embodiment. As shown in FIG. 10, the method includes the following working process: In step S1001, the first transistor, the second transistor, and the third transistor are turned on, the data signal terminal inputs a reset signal, and the first power signal terminal inputs the first voltage control. The light emitting device is turned off.
- step S1002 the first transistor, the second transistor, and the third transistor are kept turned on, and the first power signal terminal inputs a second voltage to precharge one end of the light emitting device.
- step S1003 the third transistor is turned off, and the data signal terminal inputs a data signal to cause the pixel circuit data to be written.
- step S1004 the second transistor is turned off, the third transistor is turned on, and the current of the first transistor and the third transistor drives the light emitting device to emit light.
- the switching and charging and discharging control of the circuit by using a plurality of transistors and capacitors can make the current for driving the light emitting device through the transistor independent of the threshold voltage of the transistor, and compensate for the transistor due to The difference in current flowing through the light-emitting device caused by the inconsistency or offset of the threshold voltage improves the uniformity of the brightness of the display device and significantly improves the display effect.
- the pixel circuit of such a structure has a simple structure and a small number of transistors, the area of the light-shielding region covering the transistor can be reduced, and the aperture ratio of the display device can be effectively increased.
- the light emitting device in the embodiment of the present invention may be a plurality of conventional current driving light emitting devices including LEDs or OLEDs.
- the fourth transistor can be used to control the signal input of the first power voltage terminal. Specifically, a fourth transistor can correspond to a column of pixel circuits.
- the gate of the fourth transistor is connected to the control line, the first pole is connected to the first power voltage terminal, and the second pole is connected to the control power line.
- the fourth transistor may be an N-type transistor or a P-type transistor.
- the first transistor, the second transistor, and the third transistor may each be an N-type transistor; or the first transistor, the second transistor, and the third transistor may each be a P-type transistor.
- the method includes: a first stage: the first control signal end and the second control signal end both input a high level, the first power signal end inputs a low level, and the data signal end inputs a low level reset signal.
- the second stage the first control signal end, the second control signal end and the first power signal end input a high level, and the data signal end inputs a low level reset signal.
- step S1001 may specifically include:
- the first control signal terminal S 1 and the second control signal terminal S2 both input a high level, the first power signal terminal ELVDD inputs a low level (Vss ), and the data signal terminal DATA inputs a low level reset signal (Vref ), wherein Vref-Vth>Vss (Vth is the threshold voltage of the T1 transistor).
- the step is a reset phase, as shown in FIG. 2, in the reset phase (P1), the first control signal terminal S1 and the second control signal terminal S2 are both input with a high level, and the first power signal terminal ELVDD input is low. Level (Vss), the data signal terminal DATA inputs a low level reset signal (Vref).
- Vss Level
- Vref low level reset signal
- the first transistor T1, the second transistor T2, and the third transistor T3 is turned on, the anode voltage of the light-emitting device L is Vss, and the light-emitting device L is in a closed state.
- the step S1002 may include: the first control signal terminal S1, the second control signal terminal S2, and the first power signal terminal ELVDD are both input with a high level, and the data signal terminal DATA is input with a low level reset signal (Vref). .
- This step is a compensation phase.
- the first transistor T1, the second transistor T2, and the third transistor T3 remain turned on, and the anode voltage of the light-emitting device L rises as the first transistor T1 is charged until the voltage is equal to Vref- Vth.
- the charge stored across the storage capacitor C1 is Vth.C ST , where C ST is the capacitance of the storage capacitor C1.
- Step S1003 may include: before preparing to write data, the third transistor T3 needs to be turned off, and the equivalent circuit at this time is as shown in FIG. 5, and the gate voltage of the first transistor T1 is a low level input by the data signal terminal DATA.
- the reset signal Vref at this time, the anode voltage of the light-emitting device L is now Vref-Vth.
- the step is a data writing phase.
- the first control signal terminal S 1 and the first power signal terminal ELVDD are both input with a high level
- the second control signal terminal S2 is input with a low level
- the data signal terminal DATA is input with a high level.
- Step S1004 may include: closing the second transistor T2 before the pixel circuit is ready to drive the light emitting device to emit light.
- the step is an illumination phase.
- the first power signal terminal ELVDD and the second control signal terminal S2 are both input with a high level
- the first control signal terminal S 1 and the data signal terminal DATA are both input with a low level, so that the first The three transistor T3 is turned on, and the voltage Vgs between the gate and the source of the first transistor T1 is (la) (Vdata - Vref) + Vth.
- the current flowing through the first transistor T1, the third transistor T3, and the light emitting device L is: I It can be seen from the above formula that the current of the light-emitting device L is independent of the TFT threshold voltage and the voltage across the OLED, thereby effectively eliminating the influence of the threshold voltage non-uniformity and drift.
- the structure uses a small number of TFTs and a simple control signal, which is suitable for high-resolution pixel design.
- the timing of the control signal may also be as shown in FIG. 2, including: the first stage: the control line and the second The control signal terminal inputs a high level, the first power signal terminal inputs a low level, and the data signal terminal inputs a low level reset signal.
- the second stage the control line, the second control signal end and the first power signal end are all input with a high level, and the data signal end inputs a low level reset signal.
- the third stage the control line and the first power signal end input a high level, the second control signal end inputs a low level, and the data signal end inputs a high level data signal.
- the fourth stage the first power signal end and the second control signal end both input a high level, and both the control line and the data signal end input a low level.
- the column signal circuit shown in FIG. 9 can also be driven by the timing signal design as shown in FIG. 2, except that the timing of the first power signal terminal ELVDD is used as the control line EL at this time.
- the timing of the input signal can be divided into four stages. For details, refer to the foregoing embodiments, and details are not described herein.
Abstract
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CN103680406B (zh) * | 2013-12-12 | 2015-09-09 | 京东方科技集团股份有限公司 | 一种像素电路及显示装置 |
CN103943067B (zh) | 2014-03-31 | 2017-04-12 | 京东方科技集团股份有限公司 | 一种像素电路及其驱动方法、显示装置 |
CN104517572B (zh) * | 2014-12-22 | 2017-05-03 | 深圳市华星光电技术有限公司 | Amoled像素电路 |
JP2017134145A (ja) * | 2016-01-26 | 2017-08-03 | 株式会社ジャパンディスプレイ | 表示装置 |
KR102546774B1 (ko) * | 2016-07-22 | 2023-06-23 | 삼성디스플레이 주식회사 | 표시 장치 및 그 구동 방법 |
CN106782325A (zh) * | 2017-03-02 | 2017-05-31 | 深圳市华星光电技术有限公司 | 像素补偿电路及驱动方法、显示装置 |
CN107134261B (zh) * | 2017-06-28 | 2019-07-12 | 武汉华星光电半导体显示技术有限公司 | 像素电路及其控制方法、显示面板 |
CN107393475A (zh) * | 2017-08-10 | 2017-11-24 | 京东方科技集团股份有限公司 | 像素驱动电路、像素驱动方法和显示装置 |
CN107301845A (zh) * | 2017-08-23 | 2017-10-27 | 深圳市华星光电半导体显示技术有限公司 | 像素驱动电路及其驱动方法 |
CN108062932B (zh) * | 2017-12-20 | 2020-05-26 | 北京航空航天大学 | 一种有机薄膜晶体管构造的像素电路 |
CN110831300A (zh) * | 2019-12-24 | 2020-02-21 | 深圳创维-Rgb电子有限公司 | Led矩阵调光电路、方法及电子设备 |
CN111292694B (zh) * | 2020-02-18 | 2021-06-01 | 深圳市华星光电半导体显示技术有限公司 | 像素驱动电路及其驱动方法、显示面板 |
US11315516B2 (en) | 2020-03-23 | 2022-04-26 | Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd. | Method of driving pixel driving circuit solving problems of greater power consumption of blue phase liquid crystal panel |
CN115602119A (zh) * | 2021-07-08 | 2023-01-13 | 乐金显示有限公司(Kr) | 像素电路及包括其的显示面板 |
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