WO2016029577A1 - 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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- WO2016029577A1 WO2016029577A1 PCT/CN2014/092554 CN2014092554W WO2016029577A1 WO 2016029577 A1 WO2016029577 A1 WO 2016029577A1 CN 2014092554 W CN2014092554 W CN 2014092554W WO 2016029577 A1 WO2016029577 A1 WO 2016029577A1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/0416—Control or interface arrangements specially adapted for digitisers
- G06F3/04166—Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving
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- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/0416—Control or interface arrangements specially adapted for digitisers
- G06F3/0418—Control or interface arrangements specially adapted for digitisers for error correction or compensation, e.g. based on parallax, calibration or alignment
- G06F3/04184—Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
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- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/042—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by opto-electronic means
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- 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]
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- 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
- G09G3/3258—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 voltage across the light-emitting element
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
- H10K59/40—OLEDs integrated with touch screens
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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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- G09G2320/0626—Adjustment of display parameters for control of overall brightness
Definitions
- the present disclosure relates to a pixel circuit, a driving method thereof, and a display device.
- OLED Organic Light Emitting Diode
- OLEDs are current driven and require a constant current to control illumination.
- how to solve the impact of threshold voltage drift is one of the issues that need to be paid attention to when designing pixel circuits.
- an embodiment of the present disclosure provides a pixel circuit including: a display unit and a touch unit, the display unit including: a light emitting element, a driving transistor, a storage capacitor, a power switch module, a precharge module, and a compensation module, wherein
- the pre-charging module is configured to charge a control terminal of the driving transistor and maintain the function of the storage capacitor to maintain a state of conduction between the compensation module and the storage capacitor;
- the compensation module is used for Compensating for the data signal and writing the compensated data signal to the storage capacitor;
- the power switch module is configured to input an operating voltage to the driving transistor after the data signal is written into the storage capacitor; the driving transistor
- the light emitting element is driven to emit light using a data signal stored in the storage capacitor.
- the touch unit includes: an initialization module, a touch module, and an output control module, wherein the initialization module is configured to initialize the touch module while the pre-charge module is working; the touch module The output control module is configured to open an output path and output a touch signal collected by the touch module while the compensation module is working.
- one end of the light emitting element is connected to the ground end, and the other end is connected to the second end of the driving transistor; the first end of the driving transistor is connected to the second end of the power switch module, and the control end is connected.
- a first end of the storage capacitor a first end of the power switch module is connected to an input voltage input end, and a control end inputs an illumination control signal;
- a second end of the storage capacitor is connected to the ground end;
- the module is connected to the second end of the power switch module, the control end of the driving transistor, and the first control signal line;
- the compensation module is connected to the data signal line, the control end of the driving transistor, and the second control signal line .
- the initialization module is connected to the input end of the touch module, and is connected to the first control signal line and the initialization signal line;
- the output control module is connected to the output end of the touch module, and The second control signal line and the signal read line are connected.
- the touch module is a light sensing touch module or a capacitive touch module.
- the touch module includes a photoreceptor tube and a first capacitor, wherein a first end of the photoreceptor tube is connected to a control end of the photoreceptor tube and a first end of the first capacitor, and The input end of the touch module is connected to the initialization module, and the second end of the photosensitive tube is connected to the second end of the first capacitor, and serves as an output end of the touch module and the output control The modules are connected.
- the touch module includes a first transistor and a second capacitor, wherein a control end of the first transistor is connected to a first end of the second capacitor, and serves as an input end of the touch module.
- the second end of the first transistor is connected to the output control module as an output end of the touch module, and the first end of the first transistor and the second capacitor are The second end is connected to the common voltage input.
- the initialization module is a second transistor and the output control module is a third transistor.
- the compensation module includes a fourth transistor and a fifth transistor, the first end of the fourth transistor is connected to the data signal line, and the second end is connected to the first end of the fifth transistor, and is controlled.
- the terminal is connected to the second control signal line; the second end of the fifth transistor is connected to the control terminal of the fifth transistor, and is connected to the control terminal of the driving transistor.
- the pre-charge module is a sixth transistor
- the power switch module is a seventh transistor
- all of the transistors have the same channel type.
- the channel type of the seventh transistor is opposite to the channel type of the fourth transistor, and the control terminal of the seventh transistor is connected to the second control signal line.
- Embodiments of the present disclosure also provide a display device including any of the pixel circuits described above.
- an embodiment of the present disclosure further provides a driving method of a pixel circuit, including: precharging a module to charge a control terminal of a driving transistor, causing a potential of the control terminal to become an operating voltage, and functioning at the storage capacitor Holding, so that the compensation module maintains a conductive state between the storage capacitors, and the initialization module in the touch unit initializes the touch module; the compensation module compensates the data signal and loads the compensated data signal Go to the control terminal of the driving transistor, and write the storage capacitor, and the output control module in the touch unit turns on the output path, and outputs the touch signal collected by the touch unit to the signal reading line;
- the touch unit is simultaneously turned on by a power switch module, and an operating voltage is input to the driving transistor, and the driving transistor drives the light emitting element to emit light by using a data signal stored in the storage capacitor.
- An embodiment of the present disclosure provides a pixel circuit, a driving method thereof, and a display device.
- the pixel circuit includes: a display unit and a touch unit, and the display unit includes: a light emitting element, a driving transistor, a storage capacitor, a power switch module, and a precharge
- the module and the compensation module, the touch unit includes an initialization module, a touch module and an output control module.
- the working process of the above display unit includes three stages of pre-charging, loading and driving illumination.
- the control terminal of the driving transistor is charged by the pre-charging module to make the potential of the control terminal become the working voltage, and the function of the storage capacitor Hold down to open the compensation module to the output path of the control terminal of the driving transistor; during the loading phase, the compensation module compensates the data signal and writes the compensated data signal to the storage capacitor; driving the illumination phase, using the data stored in the storage capacitor
- the signal voltage drives the light emitting element to emit light.
- the touch unit in the embodiment of the present disclosure performs synchronous operation as follows: in the pre-charging stage, the initialization module in the touch unit initializes the touch module; in the loading phase, the output control module is turned on, and the touch control unit is activated. The unit collects and outputs the touch signal in the corresponding area; during the driving illumination phase, the touch unit is turned off.
- Figure 1 is a schematic diagram of an original 2T1C pixel circuit
- FIG. 2 is a schematic diagram of a pixel circuit according to an embodiment of the present disclosure
- FIG. 3 is a flowchart of a driving method of a pixel circuit according to an embodiment of the present disclosure
- FIG. 4 is a schematic diagram of a pixel circuit according to another embodiment of the present disclosure.
- Figure 5 is a timing diagram of the pixel circuit shown in Figure 4.
- FIG. 6 is a schematic diagram of a pixel circuit according to another embodiment of the present disclosure.
- Figure 7 is a timing diagram of the pixel circuit shown in Figure 6;
- FIG. 8 is a schematic diagram of a pixel circuit according to another embodiment of the present disclosure.
- FIG. 9 is a schematic diagram of a pixel circuit according to another embodiment of the present disclosure.
- FIG. 10 is a schematic diagram showing potential changes of a detecting electrode when a finger is touched according to another embodiment of the present disclosure.
- FIG. 11 is a schematic diagram of a pixel arrangement of a display device according to another embodiment of the present disclosure.
- FIG. 1 shows a schematic diagram of the original 2T1C pixel circuit.
- the I OLED is a current generated by the Vdata signal acting on the saturation region of the driving thin film transistor (DTFT). It drives the OLED to emit light.
- I OLED is only required to be related to Vdata, but in fact, due to process process and device aging, etc., the threshold voltage (V th ) of DTFT at each pixel has unevenness (known as threshold voltage drift problem). This causes the current flowing through each pixel point OLED to change due to the change in Vth , thereby affecting the display effect of the entire image.
- the pixel circuit includes: a display unit 10 and a touch unit 20; the display unit 10 includes: a light-emitting element 11 (such as an OLED in the figure), and a driving transistor M2.
- a light-emitting element 11 such as an OLED in the figure
- the touch unit 20 includes: an initialization module 21, a touch module 22, and an output control module 23, wherein the initialization module 21 is configured to initialize the touch module 22 while the pre-charge module 13 is operating; the touch module 22 The output control module 23 is configured to open the output path and output the touch signal collected by the touch module 22 while the compensation module 14 is working.
- the working process of the display unit 10 includes three stages of pre-charging, signal loading and driving illumination: the pre-charging stage, charging the control terminal of the driving transistor M2 by the pre-charging module 13, for example, The potential of the control terminal is pulled high, so that the compensation module 14 is kept in a conducting state between the control terminal of the driving transistor M2 and the storage capacitor C, and the conduction state continues until the next state due to the retention of the storage capacitor C.
- the phase that is, continues until the data signal is written into the storage capacitor C; during the signal loading phase, the compensation module 14 compensates the data signal and writes the compensated data signal to the storage capacitor C; during the driving illumination phase, the power switch module 12 is turned on, working The voltage input drives the transistor M2, and the driving transistor M2 drives the light-emitting element 11 to emit light by using a data signal stored in the storage capacitor C.
- the touch unit 20 performs the following operations in synchronization: in the pre-charging stage of the operation of the display unit 10, the initialization module 21 in the touch unit 20 of the present embodiment initializes the touch module 22; During the signal loading phase of the operation, the output control module 23 is turned on, and the touch signal collected by the touch module 22 is output to the outside. During the driving illumination phase in which the display unit 10 operates, the connection between the initialization module 21 and the output control module 23 and the outside world are both Turning off, the touch unit 20 is turned off.
- the pixel circuit provided by the embodiment of the present disclosure can not only compensate the threshold voltage drift of the driving transistor, but also improve the uniformity of the brightness of the display panel, and can also emit light without increasing the circuit structure and operation complexity.
- Display and touch functions are integrated to simplify operations and manufacturing processes.
- the display panel or device of the above pixel circuit can simultaneously realize the light emitting display and the touch function.
- one end of the light-emitting element 11 is connected to the ground GND, and the other end is connected to the second end of the driving transistor M2; the first end of the driving transistor M2 is connected to the second end of the power switch module 12; The first end of the power switch module 12 is connected to the working voltage input terminal Vdd, and the control terminal inputs the lighting control signal EM; the first end of the storage capacitor C is connected to the control end (node a) of the driving transistor M2, and the second end is connected to the ground GND Connected; the precharge module 13 is used to charge the control terminal (node a) of the driving transistor M2, and is connected to the second end of the power switch module 12, the control terminal of the driving transistor M2, the first control signal line Scan1, and the compensation module 14; The compensation module 14 is configured to compensate the data signal and write the compensated data signal to the storage capacitor C, and the data signal line Data, the driving transistor The control terminal of M2 is connected to the second control signal line Scan2.
- the touch unit 20 is configured to implement the touch function, and includes an initialization module 21, an output control module 23, and a touch module 22.
- the initialization module 21 is connected to the input end of the touch module 22, and is connected to the first control signal line Scan1. And initializing the signal line (the data signal line Data in the figure), the initialization module 21 is configured to initialize the touch module 22 by using the Data signal under the control of the first control signal line Scan1; the touch module 22 is used for the corresponding area
- the touch control signal is collected; the output control module 23 is connected to the output end of the touch module 22, and is connected to the second control signal line Scan2 and the signal read line Readline, and the output control module 23 is used for the second control signal line Scan2.
- the touch signal collected by the touch module 22 is output to the signal read line Read line under control.
- the touch module 22 is a light touch control module or a capacitive touch module
- the initialization module 21 is a second transistor N2
- the output control module 23 is a third transistor N3.
- the pixel circuit provided by the embodiment of the present disclosure integrates the display unit 10 that drives the light-emitting display function and the touch-control unit 20 that implements the touch function by signal line multiplexing, thereby realizing the AMOLED display and the touch function. Efficient integration.
- the present embodiment provides a power switch module 12 at the operating voltage input terminal Vdd and performs control by using the illumination control signal EM.
- the illumination time of the illumination element 11 can be controlled; on the other hand, the operation can be utilized.
- the voltage (the operating voltage, that is, the voltage at the input of the operating voltage) is charged and reset to the control terminal of the driving transistor M2 and the end of the storage capacitor C connected to the control terminal, thereby eliminating the influence of the signal of the previous frame.
- This purpose is achieved by the pre-charging module 13 and the power switch module 12, and is implemented under the control of the first control signal line Scan1, which is referred to as the pre-charging stage of the display unit 10.
- the compensation module 14 compensates the data signal under the control of the second control signal line Scan2 and writes the compensated data signal to the storage capacitor C. This stage is called the signal loading phase of the display unit 10. .
- the power switch module 12 is turned on under the control of the light emission control signal EM, and the operating voltage is input to the first end of the driving transistor M2, and the data signal stored in the storage capacitor C drives the light emitting element 11 to emit light for display. It can be seen from the above working process that the display unit 10 can implement the reset and compensation functions.
- the pixel circuit further includes a touch unit 20 for implementing a touch function.
- the touch unit 20 shares the first control signal line Scan1 and the second control signal line Scan2 with the display unit 10, and in the pre-charge phase of the display unit 10,
- the initialization module 21 of the touch unit 20 initializes the touch module 22 under the control of the first control signal line Scan1; during the signal loading phase of the display unit 10, the output control module 23 is turned on under the control of the second control signal line Scan2,
- the touch signal collected by the touch module 22 is output to The signal reading line is in the driving illumination stage of the display unit 10, and the touch unit 20 is turned off to avoid affecting the display unit 10.
- the touch unit 20 can directly use the data signal or the working voltage signal when initializing, that is, the initial signal line can be omitted, and the touch unit 20 is directly connected to the data signal line Data or the working voltage input terminal Vdd.
- the pixel circuit provided by the embodiment of the present disclosure can not only compensate the threshold voltage drift of the driving transistor, improve the uniformity of the brightness of the display panel, but also can display the light emitting display and the touch function without increasing the circuit structure and operation complexity. Integrated to achieve simplified operation and manufacturing processes.
- the display panel or device of the above pixel circuit can simultaneously realize the light emitting display and the touch function.
- An embodiment of the present disclosure further provides a driving method of a pixel circuit, which is applicable to the above pixel circuit. As shown in FIG. 3, the method includes:
- the pre-charging module 13 charges the control terminal of the driving transistor M2, so that the potential of the control terminal becomes the operating voltage, and is maintained by the storage capacitor C, so that the compensation module 14 and the storage capacitor C remain conductive.
- the initialization module in the touch unit 20 initializes the touch module.
- the pixel circuit of the embodiment includes a display unit 10 and a touch unit 20.
- the working process of the display unit 10 includes three stages of pre-charging, signal loading and driving illumination. This step is a pre-charging stage of the display unit 10, and the pre-charging module 13 is provided.
- the power switch module 12 cooperates to charge the control terminal of the driving transistor M2, and resets the potential of the control terminal to the operating voltage, and resets the control terminal of the driving transistor M2 and the storage capacitor C connected to the control terminal.
- the potential of the control terminal is raised to maintain the state of the compensation module 14 between the control terminal of the driving transistor M2 and the storage capacitor C, and the state of the conduction is stored. The holding action of the capacitor C continues until the next stage, that is, until the data signal is written to the storage capacitor C.
- the precharge module 13 charges the control terminal (ie, node a) of the driving transistor M2 by using the operating voltage signal under the control of the first control signal line Scan1, and the initialization module 21 in the touch unit 20 is at the same time.
- the touch module 22 is initialized by the data signal under the control of the control signal line Scan1, and the data signal line Data in FIG. 2 also serves as the initialization signal line.
- the compensation module 14 compensates the data signal and loads the compensated data signal to the control end of the driving transistor M2, and writes the storage capacitor C, and the output control module 23 in the touch unit 20 turns on the output path to touch
- the touch signal collected by the control unit 22 is output to the signal read line Read line.
- the compensation module 14 writes the compensated data signal to the storage capacitor C under the control of the second control signal line Scan2; the output control module 23 in the touch unit 20 is turned on under the control of the second control signal line Scan2.
- the touch unit 20 collects the touch signals of the corresponding areas and outputs the signals to the signal read line Read line. This step corresponds to the signal loading phase of the display unit 10 and the acquisition and output phase of the touch unit 20.
- the touch unit 20 is turned off, and the power switch module 12 is turned on, and the operating voltage is input to the driving transistor M2.
- the driving transistor M2 drives the light emitting element 11 to emit light by using the data signal voltage stored in the storage capacitor C.
- the touch unit 20 is disconnected from other modules, and the touch unit 20 is in a closed state.
- the power switch module 12 is turned on so that the operating voltage is input to the first end of the driving transistor M2, and the driving transistor M2 drives the light emitting element 11 to emit light by using the data signal stored in the storage capacitor C, corresponding to the driving of the display unit 10.
- Luminous stage under the control of Scan1 and Scan2, the touch unit 20 is disconnected from other modules, and the touch unit 20 is in a closed state.
- the power switch module 12 is turned on so that the operating voltage is input to the first end of the driving transistor M2, and the driving transistor M2 drives the light emitting element 11 to emit light by using the data signal stored in the storage capacitor C, corresponding to the driving of the display unit 10.
- the pixel circuit and the driving method thereof provided by the embodiments of the present disclosure can not only compensate the threshold voltage drift of the driving transistor, but also improve the uniformity of the brightness of the OLED display panel, and can also touch without increasing the circuit structure and operation complexity.
- the control unit is integrated in the pixel circuit for the purpose of simplifying the operation and manufacturing process.
- This embodiment provides a pixel circuit. As shown in FIG. 4, the difference from the first embodiment is as follows:
- the compensation module 14 in the display unit 10 of the present embodiment includes: a fourth transistor T4 and a fifth transistor M5.
- the first end of the fourth transistor T4 is connected to the data signal line Data, and the second end is connected to the first end of the fifth transistor M5.
- the control terminal is connected to the second control signal line Scan2;
- the second end of the fifth transistor M5 is connected to the control terminal of the fifth transistor M5, and is connected to the control terminal of the driving transistor M2.
- the pre-charge module 13 in this embodiment is the sixth transistor T6, and the power switch module 12 is the seventh transistor T7.
- the first end of the seventh transistor T7 is connected to the working voltage input end, the control end inputs the illumination control signal EM, the second end is connected to the first end of the sixth transistor T6; the second end of the sixth transistor T6 is controlled by the driving transistor M2
- the second terminal of the sixth transistor T6 is also connected to the second end of the fifth transistor M5 and the control terminal, and the control terminal of the sixth transistor T6 is connected to the first control signal line Scan1.
- the touch unit 20 in the embodiment is, for example, a light-sensitive touch unit, and can realize light-sensitive touch.
- the touch unit 20 of the present embodiment includes: a touch module 22, which is composed of a photosensitive tube G1 and a first capacitor C1, and is a light sensing touch module; a second thin film transistor N2 as the initialization module 21; The third thin film transistor N3 of the control module 23.
- the first end of the photoreceptor G1, the control end of the photoreceptor G1, and the first end of the first capacitor C1 are connected to each other
- the second end of the second thin film transistor N2 is connected to the input end of the touch module 22, the second end of the photoreceptor G1 is connected to the second end of the first capacitor C1, and is connected to the output end of the touch module 22 as a third end.
- a first end of the thin film transistor N3; a first end of the second thin film transistor N2 is connected to the data signal line Data, the control end is connected to the first control signal line Scan1; and a second end of the third thin film transistor N3 is connected to the signal read line Read line,
- the control terminal is connected to the second control signal line Scan2.
- Capacitive touch uses In cell technology.
- the problems that are difficult to solve are display signal interference and RC-Loading problems caused by narrow bezels, such as touch electrodes and display devices such as LCD monitors.
- display signal interference and RC-Loading problems caused by narrow bezels, such as touch electrodes and display devices such as LCD monitors.
- RC-Loading problems caused by narrow bezels, such as touch electrodes and display devices such as LCD monitors.
- the control electrode can not affect the display characteristics of the display device itself, and these problems are currently difficult to overcome in the field.
- the pixel circuit of the present embodiment includes a display unit 10 and a touch unit 20, wherein the touch unit 20 is a light sensing type touch unit, and the photosensitive tube G1 in the touch unit 20 is a photosensitive TFT (Photo TFT).
- the photosensitive TFT photocurrent is generated, and different light intensities generate photocurrents of different intensities; the second and third transistors N2 and N3 are switching TFTs, which function to control the controllable switch.
- the fourth, sixth, and seventh transistors T4, T6, and T7 are switching TFTs, and the driving transistor M2 and the fifth transistor M5 operate in a saturation region as a driving TFT (Driving TFT), and further includes Storage capacitor C.
- the first and second control signal lines Scan1, Scan2, and the illumination control signal line EM are signal input lines for controlling the disconnection and conduction of the TFT switches in the display unit 10 and the touch unit 20, respectively.
- the second touch control signal line Scan2 and the signal read line Read Line are determined in the touch unit 20, and the second control signal line Scan2 is used to determine the coordinate in the Y direction parallel to the data signal line Data, and the signal read line The Read Line determines the coordinates of the X direction perpendicular to the data signal line Data.
- Fig. 5 is a timing chart showing the operation of the above pixel circuit shown in Fig. 4. The process of the entire pixel circuit will be described one by one in conjunction with FIG. 5. For the sake of easy understanding, we will separately describe the working process of the display unit 10 and the touch unit 20 at each stage, but the two processes are performed simultaneously in the actual working process.
- the working process of the pixel circuit of this embodiment includes three stages as follows:
- the first control signal line Scan[1] is pulled high, the second transistor N2 is turned on, and the third transistor N3 is turned off.
- the data signal is input, and the first end of the first capacitor C1 and the first end and the control end of the photosensor G1 (photo sensor) are reset to prepare for the next stage of signal acquisition.
- the timing 1 in the timing chart is the charging phase.
- T6 and T7 are turned on, and T4 is turned off.
- the signal of the operating voltage input terminal Vdd starts to charge a point through T6, and the potential at point a remains. For Vdd.
- the second control signal line Scan2 is pulled high, N3 is turned on, G1 is a light sensing TFT, and the G1 gate source is connected, and G1 passes through itself.
- the potential is converted.
- the potential difference stored by C1 is a fixed value.
- the charging current of the photosensitive tube G1 is increased, and when N3 is turned on, the signal is transmitted to the end of the amplifier through the signal read line Read line, and the amplified signal is sent to the processor for data calculation and analysis;
- the touch action compares the change in the intensity of the photoelectric signal before and after the touch with the threshold without the touch, thereby determining whether there is a touch (ie, a change in the intensity of the light illumination).
- the coordinate in the Y direction parallel to the data signal line Data is the output point of the second control signal line Scan2 at this time, and the coordinate in the X direction perpendicular to the data signal line Data is determined by the signal reading line Read Line At this point, the position coordinates of the touch point are determined.
- T4 is turned on at this time, and T6 and T7 are turned off.
- the signal Vdata on the data signal line DATA recharges the point a through M5, and the potential at point a changes from the original operating voltage Vdd to Vth1+Vdata (at this time, the voltage difference between the M5 gate sources is Vth1), that is, compensation
- the first and second control signal lines Scan1 and Scan2 are both pulled low, so that N2 and N3 are disconnected at this stage, and the touch is performed.
- the unit 20 is in an inoperative stagnation state (or a closed state), and this process corresponds to the lighting process of the display unit 10, so that its influence on the display unit 10 is small.
- the light-emitting element 11 of the present embodiment is an OLED.
- the timing 3 in the timing chart corresponds to the stage in which the AMOLED pixel is officially illuminated, and the light-emitting stages T6 and T4 are both disconnected, and the T7 is guided.
- the source (first end) potential of the driving thin film transistor M2 is connected to the operating voltage Vdd, and the current is caused to start to emit light through the M2 through T7.
- Vdata is the data voltage
- V OLED is the anode voltage of the light-emitting element 11 (OLED). It can be seen from the above formula that the operating current I OLED is not affected by Vth, which solves the threshold voltage of the driving transistor due to the process and long-term operation. (Vth) drift problem, eliminate its impact on I OLED , and ensure the normal operation of OLED.
- the pixel circuit of the embodiment provides a pixel structure design of the embedded light sensing touch module, which not only includes the AMOLED display compensation circuit, but also adds a light sensing touch unit, which can not only compensate the threshold voltage drift of the driving transistor, Improve the uniformity of brightness of the display panel, and integrate the illuminating display and touch functions to simplify the operation and manufacturing process.
- the display panel or device of the above pixel circuit can simultaneously realize the light emitting display and the light sensing touch function.
- all of the transistors N2, N3, T4, T6, T7, M2, and M5 in the above pixel circuit have the same channel type, such as an N-type, unified transistor process, which helps to improve product yield.
- the Low Temperature Poly-silicon (LTPS) process is used in the preparation.
- each of the transistors is an N-type thin film transistor, but the type of each transistor (ie, each transistor is N-type or P-type, which is depleted or enhanced) cannot be used to define
- the pixel circuit is also within the scope of the present disclosure for those skilled in the art to change the selection of each transistor and the connection variation caused by the selection change without any creative work.
- the on/off states of the sixth transistor T6 and the seventh transistor T7 in FIG. 4 are always opposite, and thus can be changed.
- Transistor selection P-type and N-type is used to reduce one signal line.
- the channel type of the seventh transistor and the channel type of the fourth transistor are set to the opposite type, and the seventh transistor control terminal can be controlled by the second control signal line Scan2 without setting the illumination control signal line.
- a variation of the pixel circuit of the present embodiment is different from the pixel circuit shown in FIG. 4 in that the seventh transistor T7 of the pixel circuit is a P-type transistor, except for the seventh transistor T7. All transistors are N-type transistors.
- the seventh transistor T7 is a P-type transistor, and its control terminal is directly connected to the second control signal line Scan2.
- FIG. 7 is a timing diagram of the pixel circuit. The pixel circuit only needs two control signal lines, Scan1 and Scan2.
- control signal line of the compensation unit and the switch control signal line of the touch unit are compatible, and the AMOLED display and the embedded optical touch function are efficiently integrated by the signal line multiplexing, thereby improving the product. Additional value.
- the pixel circuit is similar to the pixel circuit shown in FIG. 4 in the second embodiment.
- the difference is that the touch module 22 in the touch unit 20 is a capacitive touch.
- the module includes: a first transistor N1 and a second capacitor C2, wherein the control end of the first transistor N1 is connected to the first end of the second capacitor C2, and serves as an input end of the touch module 22 and the initialization module 21 (second The transistor N2) is connected to the second end of the first transistor N1 as an output end of the touch module 22, and is connected to the output control module 23.
- the first end of the first transistor N1 is connected to the common voltage input terminal Vcom.
- FIG. 5 The working circuit diagram of the pixel circuit of this embodiment is shown in FIG. 5, which is the same as that of the second embodiment.
- the working principle and process are also substantially the same as those of the pixel circuit shown in FIG. 4. For the sake of simplicity, only the working process will be briefly described herein.
- the timing 1 in FIG. 5 it can be seen from the timing 1 in FIG. 5 that Scan1 is pulled high, N2 in the touch unit 20 is turned on, and N3 is turned off.
- the data signal is input, and the first end of the second capacitor C2 is connected with N1.
- the console is reset to prepare for the next phase of signal acquisition.
- the timing 1 in the timing chart is the charging phase.
- T6 and T7 are turned on, and T4 is turned off.
- the operating voltage Vdd starts to charge a point through T6, and the potential at point a remains Vdd.
- the second control signal line Scan2 is pulled high, and N3 is turned on, when the finger touches the detecting electrode D (the upper pole of C2) Board), directly causing the potential of the n1 node (the control terminal of N1) to decrease, as shown in FIG. 10, at this time, the potential of the n1 node is lowered to Vdata-Vf, wherein Vf is a potential decrease due to the touch, and the potential of the n1 node is lowered.
- the gate-source voltage of N1 is still satisfied, that is, Vdata-Vf>Vth1; the current passes through N1 and N3, and is finally received by the read line Read Line. At this time, the received signal has a current compared to when it is not touched. Reduced to identify touch points.
- FIG. 10 shows potential changes of the upper plate node n1 and the lower plate node n0 of the second capacitor C2.
- T4 is turned on, T6 and T7 are turned off, and the signal Vdata on the data signal line Data recharges the point a through M5, and the potential of the point a is changed from the original operating voltage Vdd to Vth1+.
- the first and second control signal lines Scan1 and Scan2 are both pulled low, so that N1 to N3 are disconnected at this stage, and are not
- the stagnation state (or the closed state) of the work corresponds to the illuminating process of the display unit 10, so that it has the least influence on the display unit 10.
- the embodiment provides a pixel structure design of the embedded capacitive touch display module.
- the pixel includes the AMOLED display compensation circuit, and the capacitive touch unit is added, which not only compensates for the threshold voltage drift of the driving transistor, but also improves the OLED display.
- the brightness of the panel is uniform, and the touch module is integrated into the pixel circuit without increasing the circuit structure and operation complexity, so as to simplify the operation and the manufacturing process.
- all of the transistors N1, N2, N3, T4, T6, T7, M2, and M5 in the above pixel circuit have the same channel type, such as an N-type, unified transistor process, which helps to improve product yield.
- the preparation can be completed simultaneously by low temperature poly-silicon (LTPS) technology, which further simplifies the preparation process and improves product yield.
- LTPS low temperature poly-silicon
- each of the transistors may be an N-type thin film transistor, but for those skilled in the art, the selection and variation of each transistor may be selected without any creative work. Changes in connectivity resulting from changes are also within the scope of the present disclosure.
- the seventh transistor T7 of the pixel circuit is set as a P-type transistor, and all transistors except the seventh transistor T7 are It is set as an N-type transistor.
- the control terminal of the seventh transistor T7 can be directly connected to the second control signal line Scan2, and it is not necessary to set the illumination control signal EM, and one control signal line can be omitted.
- the timing diagram of the pixel circuit is shown in FIG.
- Embodiments of the present disclosure provide a pixel structure design with a built-in capacitive touch module.
- the display unit adopts a design of 5T1C (5 thin film transistors and 1 capacitor), which can solve the process of the pixel drive transistor and long-time operation.
- the problem that the threshold voltage (Vth) is inconsistent is such that the current flowing through each pixel is not affected by the threshold voltage, and finally the uniformity of image display is ensured; the pixel structure design of the embodiment can ensure that the whole process is except for the light-emitting phase. No current flows through the OLED, which indirectly increases the lifetime of the illuminating element.
- control signal line, the data signal line Data, the control signal line of the capacitive touch unit, the initialization signal line, and the like of the compensation circuit are multiplexed by the signal line without increasing the circuit structure and the operation complexity.
- the method realizes efficient integration of the light-emitting display and the capacitive touch function, and achieves Simplify operations and the purpose of the manufacturing process.
- An embodiment of the present disclosure further provides a display device provided with any one of the pixel circuits described in Embodiments 1 to 3.
- the display device may be any product or component having a display function, such as an electronic paper, an OLED panel, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator, and the like.
- the display device of the embodiment introduces the touch function into the display area of the display device, and simultaneously realizes the light-emitting display and the touch function.
- the touch module is generally disposed in a manner of periodically implanting pixels in the display area.
- each pixel circuit 200 with a touch module is a touch point, and the periodic distribution mode, distribution density, or spacing of the touch module 22 can be based on actual conditions (such as the design requirements of the touch point).
- the design is not limited in this embodiment.
- the remaining pixels employ a pixel circuit 100 having only a display unit.
- the display device of the embodiment of the present disclosure has good brightness uniformity, and integrates a module for realizing a touch function in a pixel circuit without increasing circuit structure and operation complexity, thereby achieving the purpose of simplifying operation and manufacturing process. .
- first, second, etc. are used in the present disclosure to classify similar items.
- the first and second words are not limited in number to the present disclosure, but are an example of a preferred mode. It is to be understood that those skilled in the art, in light of the disclosure of the present disclosure, are apparently within the scope of the disclosure.
- the storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).
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Abstract
一种像素电路及驱动方法、显示装置。像素电路包括:显示单元(10)和触控单元(20),显示单元(10)中的预充模块(13)对驱动晶体管(M2)的控制端充电,并在存储电容(C)作用下保持;补偿模块(14)对数据信号补偿并将补偿过的数据信号写入存储电容(C);电源开关模块(12)在数据信号写入存储电容(C)后,将工作电压输入驱动晶体管(M2);驱动晶体管(M2)利用存储在存储电容(C)中的数据信号驱动发光元件(11)发光;触控单元(20)中的初始化模块(21)在预充模块(13)工作的同时,对触控模块(22)进行初始化;触控模块(22)对相应区域内的触控信号进行采集;输出控制模块(23)在补偿模块(14)工作的同时开启输出通路,将触控模块(22)采集到的触控信号输出。像素电路能够补偿阈值电压漂移,同时将触控模块集成于像素电路中,简化操作及制造流程。
Description
本公开涉及一种像素电路及其驱动方法、显示装置。
有机发光二极管(Organic Light Emitting Diode,OLED)作为一种电流型发光器件,因其所具有的自发光、快速响应、宽视角和可制作在柔性衬底上等特点而越来越多地被应用于高性能显示领域。
与液晶显示器利用稳定的电压控制亮度不同,OLED属于电流驱动,需要稳定的电流来控制发光。对于OLED显示,如何解决阈值电压漂移带来的影响,是设计像素电路时需要关注的问题之一。
同时近年来,触控功能在各种显示面板尤其是移动显示中的应用越来越广,几乎成了智能手机的标准配置,相应地,具有触控功能的OLED显示面板已得到越来越多人们的青睐。但目前,已知技术中大都是将显示面板和触摸面板(Touch Screen Panel,TSP)分开制作,然后再进行贴合,这样的工艺流程使得显示触摸屏功能面板的工艺复杂,成本高,也不利于显示的轻薄化。TSP in cell(TSP内置)技术则是将显示和触控功能进行整合,使用一道工艺流程即可完成,而不用分成两道流程,因此不仅拥有低成本的优势,还能使得工艺简单,显示触摸面板更加轻薄。但是对于如何完美地将触控电路与像素电路集成,目前还没有很好的解决方案。
发明内容
一方面,本公开的实施例提供一种像素电路,包括:显示单元和触控单元,所述显示单元包括:发光元件、驱动晶体管、存储电容、电源开关模块、预充模块和补偿模块,其中,所述预充模块用于对驱动晶体管的控制端充电,并在所述存储电容的作用下保持,以使得所述补偿模块到存储电容之间保持导通的状态;所述补偿模块用于对数据信号进行补偿并将经过补偿的数据信号写入所述存储电容;所述电源开关模块用于在数据信号写入所述存储电容后,将工作电压输入所述驱动晶体管;所述驱动晶体管利用存储在所述存储电容中的数据信号驱动所述发光元件发光。
所述触控单元包括:初始化模块、触控模块和输出控制模块,其中,所述初始化模块用于在所述预充模块工作的同时,对所述触控模块进行初始化;所述触控模块用于对相应区域内的触控信号进行采集;所述输出控制模块用于在所述补偿模块工作的同时开启输出通路,将所述触控模块采集到的触控信号输出。
可选地,所述发光元件的一端与接地端相连,另一端与所述驱动晶体管的第二端相连;所述驱动晶体管的第一端连接所述电源开关模块的第二端,控制端连接所述存储电容的第一端;所述电源开关模块的第一端连接工作电压输入端,控制端输入发光控制信号;所述存储电容的第二端与所述接地端相连;所述预充模块与所述电源开关模块的第二端、所述驱动晶体管的控制端以及第一控制信号线相连;所述补偿模块与数据信号线、所述驱动晶体管的控制端以及第二控制信号线相连。
可选地,所述初始化模块与所述触控模块的输入端相连,并连接所述第一控制信号线、初始化信号线;所述输出控制模块与所述触控模块的输出端相连,并连接所述第二控制信号线和信号读取线。
可选地,所述触控模块为光感式触控模块,或者电容式触控模块。
可选地,所述触控模块包括感光管和第一电容,其中,所述感光管的第一端与所述感光管的控制端,以及所述第一电容的第一端相连,并作为所述触控模块的输入端与所述初始化模块相连,所述感光管的第二端与所述第一电容的第二端相连,并作为所述触控模块的输出端与所述输出控制模块相连。
可选地,所述触控模块包括第一晶体管和第二电容,其中,所述第一晶体管的控制端与所述第二电容的第一端相连,并作为所述触控模块的输入端与所述初始化模块相连,所述第一晶体管的第二端作为所述触控模块的输出端,与所述输出控制模块相连,所述第一晶体管的第一端、所述第二电容的第二端均与公共电压输入端相连。
可替换地,所述初始化模块为第二晶体管,所述输出控制模块为第三晶体管。
可选地,所述补偿模块包括第四晶体管和第五晶体管,所述第四晶体管的第一端与所述数据信号线相连,第二端与所述第五晶体管的第一端相连,控制端与所述第二控制信号线相连;所述第五晶体管的第二端与所述第五晶体管的控制端相连,并连接所述驱动晶体管的控制端。
可替换地,所述预充模块为第六晶体管,所述电源开关模块为第七晶体管。
可选地,所有所述晶体管均具有相同的沟道类型。
可替换地,所述第七晶体管的沟道类型与所述第四晶体管的沟道类型相反,所述第七晶体管的控制端与所述第二控制信号线相连。
本公开的实施例还提供一种显示装置,包括上面所述的任一像素电路。
另一方面,本公开的实施例还提供一种像素电路的驱动方法,包括:预充模块对驱动晶体管的控制端充电,使该控制端的电位变为工作电压,并在所述存储电容的作用下保持,以使得所述补偿模块到存储电容之间保持导通的状态,同时触控单元中的初始化模块对触控模块进行初始化;补偿模块对数据信号进行补偿并将经过补偿的数据信号加载到所述驱动晶体管的控制端,并写入所述存储电容,同时触控单元中的输出控制模块开启输出通路,将所述触控单元采集到的触控信号输出至信号读取线;关闭所述触控单元,同时电源开关模块开启,工作电压输入所述驱动晶体管,所述驱动晶体管利用存储在所述存储电容中的数据信号驱动所述发光元件发光。
本公开的实施例提供一种像素电路及其驱动方法、显示装置,所述像素电路包括:显示单元和触控单元,显示单元包括:发光元件、驱动晶体管、存储电容、电源开关模块、预充模块和补偿模块,触控单元包括初始化模块、触控模块和输出控制模块。上述显示单元的工作过程包括预充、加载和驱动发光三个阶段,在预充阶段,由预充模块对驱动晶体管的控制端充电使该控制端的电位变为工作电压,并在存储电容的作用下保持,以开通补偿模块到驱动晶体管控制端的输出通路;加载阶段,由补偿模块对数据信号进行补偿并将经过补偿的数据信号写入存储电容;驱动发光阶段,利用存储在存储电容中的数据信号电压驱动发光元件发光。上述显示单元工作的同时,本公开的实施例中的触控单元同步进行工作如下:预充阶段,触控单元中的初始化模块对触控模块进行初始化;加载阶段,输出控制模块开启,触控单元采集相应区域内的触控信号并输出;驱动发光阶段,触控单元关闭。
图1为原始的2T1C像素电路示意图;
图2为本公开的一个实施例提供的像素电路示意图;
图3为本公开的一个实施例提供的像素电路的驱动方法流程图;
图4为本公开的另一实施例提供的像素电路示意图;
图5为图4所示像素电路的时序图;
图6为本公开的另一实施例提供的像素电路的一种变形;
图7为图6所示像素电路的时序图;
图8为本公开的另一实施例提供的像素电路示意图;
图9为本公开的另一实施例提供的像素电路的一种变形;
图10为本公开的另一实施例中手指触控时探测电极的电势变化示意图;
图11为本公开的另一实施例提供的显示装置的像素排布示意图。
图1示出了原始的2T1C像素电路示意图。在原始的2T1C像素电路中,IOLED是由于Vdata信号作用在驱动薄膜晶体管(DTFT)饱和区域而产生的电流。它驱动OLED来发光,公式为IOLED=K(VGS-Vth)2,其中VGS为栅源电压差,VGS=Vdata-Vdd,Vdd为恒定工作电压,Vth为DTFT的阈值电压。为达到更佳显示效果,要求IOLED只与Vdata有关,但实际上由于工艺制程和器件老化等原因,各像素点的DTFT的阈值电压(Vth)存在不均匀性(通称阈值电压漂移问题),这样就导致了流过每个像素点OLED的电流因Vth的变化而变化,从而影响整个图像的显示效果。
下面将结合附图,对本公开的实施例中的技术方案进行清楚、完整地描述,显然,所描述的实施例仅仅是本公开的一部分实施例,而不是全部的实施例。
本公开的实施例提供一种像素电路,如图2所示,该像素电路包括:显示单元10和触控单元20;显示单元10包括:发光元件11(如图中的OLED)、驱动晶体管M2、存储电容C、电源开关模块12、预充模块13和补偿模块14,其中,预充模块13用于对驱动晶体管M2的控制端充电,并在存储电容C的作用下保持,以使得补偿模块14到存储电容C之间保持导通的状态;补偿模块14用于对数据信号进行补偿并将经过补偿的数据信号写入存储电容C;电源开关模块12用于在数据信号写入存储电容C后,将工作电压输入驱动晶体管M2;驱动晶体管M2利用存储在存储电容C中的数据信号驱动发光元件11发光。
其中,触控单元20包括:初始化模块21、触控模块22和输出控制模块23,其中,初始化模块21用于在预充模块13工作的同时,对触控模块22进行初始化;触控模块22用于对相应区域内的触控信号进行采集;输出控制模块23用于在补偿模块14工作的同时开启输出通路,将触控模块22采集到的触控信号输出。
本公开的实施例提供的像素电路,显示单元10的工作过程包括预充、信号加载和驱动发光三个阶段:预充阶段,由预充模块13对驱动晶体管M2的控制端充电,例如使该控制端的电位拉高,从而使补偿模块14到驱动晶体管M2的控制端及存储电容C之间保持导通的状态,并且该导通的状态因存储电容C的保持作用,会一直持续至下一阶段,即持续到数据信号写入存储电容C之后;信号加载阶段,补偿模块14对数据信号进行补偿并将经过补偿的数据信号写入存储电容C;驱动发光阶段,电源开关模块12开启,工作电压输入驱动晶体管M2,驱动晶体管M2利用存储在存储电容C中的数据信号驱动发光元件11发光。上述显示单元10工作的同时,触控单元20同步进行工作如下:在显示单元10工作的预充阶段,本实施例触控单元20中初始化模块21对触控模块22进行初始化;在显示单元10工作的信号加载阶段,输出控制模块23开启,将触控模块22采集到的触控信号输出至外部,在显示单元10工作的驱动发光阶段,初始化模块21和输出控制模块23与外界的连接均关断,触控单元20关闭。
综上所述,本公开的实施例提供的像素电路,不仅能够补偿驱动晶体管阈值电压漂移,提高显示面板亮度的均匀性,同时还可在不增加电路结构和操作复杂性的情况下,将发光显示和触控功能整合在一起,达到简化操作以及制造流程的目的。采用的上述像素电路的显示面板或装置,可以同时实现发光显示和触控功能。
例如,一种可选实施方式中,发光元件11的一端与接地端GND相连,另一端与驱动晶体管M2的第二端相连;驱动晶体管M2的第一端连接电源开关模块12的第二端;电源开关模块12的第一端连接工作电压输入端Vdd,控制端输入发光控制信号EM;存储电容C的第一端与驱动晶体管M2的控制端(节点a)相连,第二端与接地端GND相连;预充模块13用于对驱动晶体管M2的控制端(节点a)充电,与电源开关模块12的第二端、驱动晶体管M2的控制端、第一控制信号线Scan1以及补偿模块14相连;补偿模块14用于对数据信号进行补偿并将经过补偿的数据信号写入存储电容C,与数据信号线Data、驱动晶体管
M2的控制端以及第二控制信号线Scan2相连。
触控单元20用于实现触控功能,包括:初始化模块21、输出控制模块23和触控模块22,其中,初始化模块21与触控模块22的输入端相连,并连接第一控制信号线Scan1、初始化信号线(图中的数据信号线Data),初始化模块21用于在第一控制信号线Scan1的控制下利用Data信号对触控模块22进行初始化;触控模块22用于对相应区域内的触控信号进行采集;输出控制模块23与触控模块22的输出端相连,并连接第二控制信号线Scan2和信号读取线Readline,输出控制模块23用于在第二控制信号线Scan2的控制下将触控模块22采集到的触控信号输出到信号读取线Read line。其中可选地,触控模块22为光感式触控模块,或者电容式触控模块,初始化模块21为第二晶体管N2,输出控制模块23为第三晶体管N3。
本公开的实施例提供的像素电路,将驱动发光实现显示功能的显示单元10和实现触控功能的触控单元20通过信号线复用方式集成在一起,从而实现了AMOLED显示和触控功能的高效整合。
对显示单元10而言,本实施例在工作电压输入端Vdd设置一电源开关模块12并利用发光控制信号EM进行控制,一方面可以对发光元件11的发光时间进行控制;另一方面可以利用工作电压(工作电压即工作电压输入端的电压)对驱动晶体管M2的控制端及存储电容C与该控制端相连的一端进行充电重置,消除上一帧信号的影响。这一目的由预充模块13和电源开关模块12相互配合,并在第一控制信号线Scan1的控制下实现,称为显示单元10的预充阶段。预充阶段结束后,由补偿模块14在第二控制信号线Scan2的控制下对数据信号进行补偿并将经过补偿的数据信号写入存储电容C,这一阶段称为显示单元10的信号加载阶段。信号加载阶段完成后,在发光控制信号EM控制下电源开关模块12开启,工作电压输入驱动晶体管M2的第一端,存储在存储电容C中的数据信号驱动发光元件11发光实现显示。由上述工作过程可知,显示单元10可以实现复位、补偿功能。
上述像素电路还包括用以实现触控功能的触控单元20,触控单元20与上述显示单元10共用第一控制信号线Scan1和第二控制信号线Scan2,在显示单元10的预充阶段,触控单元20的初始化模块21在第一控制信号线Scan1控制下对触控模块22进行初始化;显示单元10的信号加载阶段,输出控制模块23在第二控制信号线Scan2的控制下开启,将触控模块22采集到的触控信号输出到
信号读取线Read line;显示单元10的驱动发光阶段,触控单元20关闭,避免影响显示单元10。其中,为减少信号线,触控单元20进行初始化时可以直接利用数据信号或者工作电压信号,即可以不设置初始信号线,触控单元20直接与数据信号线Data或者工作电压输入端Vdd相连。
本公开的实施例提供的像素电路,不仅能够补偿驱动晶体管阈值电压漂移,提高显示面板亮度的均匀性,同时还可在不增加电路结构和操作复杂性的情况下,将发光显示和触控功能整合在一起,达到简化操作以及制造流程的目的。采用的上述像素电路的显示面板或装置,可以同时实现发光显示和触控功能。
本公开的实施例还提供一种像素电路的驱动方法,适用于上述像素电路,如图3所示,该方法包括:
101、预充模块13对驱动晶体管M2的控制端充电,使该控制端的电位变为工作电压,并在存储电容C的作用下保持,以使得补偿模块14到存储电容C之间保持导通的状态,同时触控单元20中的初始化模块对触控模块进行初始化。
本实施例像素电路包括显示单元10和触控单元20,显示单元10的工作过程包括预充、信号加载和驱动发光三个阶段,本步骤为显示单元10的预充阶段,由预充模块13和电源开关模块12相互配合实现对驱动晶体管M2的控制端充电,使该控制端的电位重置为工作电压,一方面对驱动晶体管M2的控制端及与该控制端相连的存储电容C进行重置,避免上一帧信号的影响;另一方面拉高该控制端的电位,使补偿模块14到驱动晶体管M2的控制端及存储电容C之间保持导通的状态,并且该导通的状态因存储电容C的保持作用,会一直持续至下一阶段,即持续至数据信号写入存储电容C之后。
例如,本步骤预充模块13在第一控制信号线Scan1的控制下,利用工作电压信号对驱动晶体管M2的控制端(即节点a)充电,同时,触控单元20中的初始化模块21在第一控制信号线Scan1的控制下利用数据信号对触控模块22进行初始化,图2中的数据信号线Data同时也充当初始化信号线。
102、补偿模块14对数据信号进行补偿并将经过补偿的数据信号加载到驱动晶体管M2的控制端,并写入存储电容C,同时触控单元20中的输出控制模块23开启输出通路,以便触控单元22采集到的触控信号输出至信号读取线Read line。
本步骤中补偿模块14在第二控制信号线Scan2的控制下,将经过补偿的数据信号写入存储电容C;触控单元20中的输出控制模块23在第二控制信号线Scan2的控制下开启,触控单元20采集相应区域的触控信号并输出至信号读取线Read line。本步骤对应显示单元10的信号加载阶段,以及触控单元20的采集输出阶段。
103、关闭触控单元20,同时电源开关模块12开启,工作电压输入驱动晶体管M2,驱动晶体管M2利用存储在存储电容C中的数据信号电压驱动发光元件11发光。
本步骤中,在Scan1、Scan2控制下,触控单元20与其它模块断开,触控单元20处于关闭状态。而显示单元11中,电源开关模块12开启使得工作电压输入驱动晶体管M2的第一端,驱动晶体管M2利用存储在存储电容C中的数据信号驱动发光元件11发光实现显示,对应显示单元10的驱动发光阶段。
本公开的实施例提供的像素电路及其驱动方法,不仅能够补偿驱动晶体管阈值电压漂移,提高OLED显示面板亮度的均匀性,同时还可在不增加电路结构和操作复杂性的情况下,将触控单元集成于像素电路中,达到简化操作以及制造流程的目的。
本实施例提供一种像素电路,如图4所示,与实施例一的区别之处在于:
本实施例显示单元10中的补偿模块14包括:第四晶体管T4和第五晶体管M5,第四晶体管T4的第一端与数据信号线Data相连,第二端与第五晶体管M5的第一端相连,控制端与第二控制信号线Scan2相连;第五晶体管M5的第二端与第五晶体管M5的控制端相连,并连接驱动晶体管M2的控制端。
本实施例中的预充模块13为第六晶体管T6,电源开关模块12为第七晶体管T7。第七晶体管T7的第一端连接工作电压输入端,控制端输入发光控制信号EM,第二端与第六晶体管T6的第一端相连;第六晶体管T6的第二端与驱动晶体管M2的控制端相连,第六晶体管T6的第二端还与第五晶体管M5的第二端及控制端相连,第六晶体管T6的控制端与第一控制信号线Scan1相连。
与实施例一的区别之处还在于,本实施例中的触控单元20例如为光感式触控单元,可以实现光感触控。示例性地,本实施例触控单元20包括:触控模块22,由感光管G1和第一电容C1构成,为光感式触控模块;作为初始化模块21的第二薄膜晶体管N2;作为输出控制模块23的第三薄膜晶体管N3。感光管G1的第一端、感光管G1的控制端以及第一电容C1的第一端相互连接,并作
为触控模块22的输入端连接第二薄膜晶体管N2的第二端,感光管G1的第二端与第一电容C1的第二端相互连接,并作为触控模块22的输出端连接第三薄膜晶体管N3的第一端;第二薄膜晶体管N2的第一端连接数据信号线Data,控制端连接第一控制信号线Scan1;第三薄膜晶体管N3的第二端连接信号读取线Read line,控制端连接第二控制信号线Scan2。
与电容式触控对比,光感触控是根据光强变化来感知触摸点位置的,除了具备同样的触控灵敏度以外,其优点就是不受模组本身尺寸的限制。而电容式触控采用In cell(内置)技术,难以解决的问题是显示信号干扰和以及窄边框带来的RC-Loading(信号延迟)问题,如:触控电极与显示装置如液晶显示器LCD工作时所需的电极之间有相当大的寄生电容,还有在日趋窄边框化趋势下线电阻分布也很难满足要求,如何在强电场干扰的情况下顺利的采集到触控信号,同时触控电极又不能影响到显示装置本身的显示特性,这些问题都是目前该领域很难克服的。
本实施例像素电路包括显示单元10和触控单元20,其中,触控单元20为光感式触控单元,触控单元20中的感光管G1为感光TFT(Photo TFT),当光照射到感光TFT上,就会产生光电流,不同的光强会产生不同强度的光电流;第二、三晶体管N2、N3为开关TFT(Switching TFT),起到控制可控开关的作用,除此之外,还有第一电容C1,用于存储感光管G1产生的光电流。显示单元10中,第四、六、七晶体管T4、T6、T7为开关TFT(Switching TFT),驱动管M2与第五晶体管M5工作在饱和区,为驱动TFT(Driving TFT),此外,还包含存储电容C。
对于整个信号电路,第一、第二控制信号线Scan1、Scan2,以及发光控制信号线EM均为信号输入线路,分别控制显示单元10和触控单元20内TFT开关的断开和导通。触控单元20中确定触摸位置坐标的是第二控制信号线Scan2和信号读取线Read Line,第二控制信号线Scan2用于确定与数据信号线Data平行的Y方向的坐标,信号读取线Read Line确定与数据信号线Data垂直的X方向的坐标。
图5为图4所示的上述像素电路的工作时序图。下面结合图5对整个像素电路的各个过程进行逐一说明,为方便理解,每一阶段我们将显示单元10和触控单元20的工作过程分开叙述,但实际工作过程中二者是同时进行的。本实施例像素电路工作过程包括3个阶段如下:
在第1阶段,对触控单元20而言,从图5时序1中可以看到第一控制信号线Scan[1]拉高,第二晶体管N2导通,第三晶体管N3断开,此阶段数据信号输入,将第一电容C1的第一端与感光管G1(photo Sensor)的第一端及控制端重置,为下一阶段信号采集做准备。对显示单元10而言,时序图中的时序1为充电阶段,此时T6、T7导通,T4断开,工作电压输入端Vdd的信号通过T6开始对a点进行充电,a点电位会保持为Vdd。
在第2阶段,对触控单元20而言,从图5时序2中可以看到,第二控制信号线Scan2拉高,N3导通,G1为光感TFT,G1栅源连接,G1经过自身电势转换,此时C1储存的电位差为定值,当有光照射至此处,感光管G1接受到的光照强度增加,此时的电压信号暂时储存在C1一端。由于光照影响使得感光管G1充电电流增加,N3导通时,此时将此信号通过信号读取线Read line传送到末端的放大器,放大后的信号给处理器进行数据计算分析;若此期间发生触控动作,将触控前后光电信号强度变化差值与无触控阈值进行比较,据此即可判断是否有触摸(即光照射强度变化)。其中,与数据信号线Data平行的Y方向上的坐标是由此时的第二控制信号线Scan2输出点确定,与数据信号线Data垂直的X方向上的坐标就由信号读取线Read Line确定,至此也就确定了触摸点的位置坐标。
对显示单元10而言,此时T4导通,T6、T7断开。数据信号线DATA上的信号Vdata会通过M5对a点进行重新充电,a点电势由原来的工作电压Vdd变为Vth1+Vdata(此时,M5栅源之间的压差为Vth1),即补偿过的数据信号写入第一电容C1,为下一阶段做准备,此时a点电势Va=Vth1+Vdata。
在第3阶段,对触控单元20而言,从图5时序3中可以看到,第一、第二控制信号线Scan1和Scan2均拉低,因此该阶段N2、N3都断开,触控单元20处于不工作的停滞状态(或者说关闭状态),这个过程对应显示单元10的发光过程,因此其对显示单元10的影响很小。
对显示单元10而言,本实施例发光元件11为OLED,从图5可以看出,时序图中的时序3对应为AMOLED像素正式发光的阶段,该发光阶段T6、T4均断开,T7导通,驱动薄膜晶体管M2的源极(第一端)电势接入工作电压Vdd,电流通过T7经M2使得OLED开始发光。
由TFT饱和电流公式可以得到:IOLED=K(VGS–Vth2)2,式中IOLED为M2的饱和电流,Vth2为M2的阈值电压,VGS为M2的栅源电压差,VGS=Va-VOLED。
Va=Vth1+Vdata,代入上式得到:
IOLED=K(VGS–Vth2)2=K(Va-VOLED–Vth2)2
=K[(Vdata+Vth1)–VOLED–Vth2]2
=K(Vdata–VOLED)2
上式中Vth1与Vth2是M5与M2的阈值电压,根据镜像电路原理,认为Vth1与Vth2近似相等,即Vth1=Vth2。其中Vdata为数据电压,VOLED为发光元件11(OLED)的阳极电压,由上式中可知工作电流IOLED已经不受Vth的影响,解决了驱动晶体管由于工艺制程及长时间的操作造成阈值电压(Vth)漂移的问题,消除其对IOLED的影响,保证OLED的正常工作。
本实施例所述像素电路提供一种内嵌光感式触控模块的像素结构设计,不仅包含AMOLED显示补偿电路,同时还增加了光感式触控单元,不仅能够补偿驱动晶体管阈值电压漂移,提高显示面板亮度的均匀性,同时将发光显示和触控功能整合在一起,达到简化操作以及制造流程的目的。采用的上述像素电路的显示面板或装置,可以同时实现发光显示和光感触控功能。
可替换地,上述像素电路中的所有晶体管N2、N3、T4、T6、T7、M2、M5均具有相同的沟道类型例如N型,统一晶体管工艺制程,有助于提高产品良率。可替换地,制备时采用低温多晶硅(Low Temperature Poly-silicon,LTPS)工艺制程。
在本公开的实施例中,所述各晶体管均为N型薄膜晶体管,但所述各晶体管的型号(即各晶体管是N型或P型,是耗尽型或增强型)并不能用于限定像素电路,对于本领域普通技术人员来讲,在不付出创造性劳动的前提下,对各晶体管的选型变化及因选型变化产生的连接变动,也在本公开的保护范围之内。
例如,因为图5所示时序图中,Scan2和发光控制信号EM总是对称翻转的,图4中第六晶体管T6和第七晶体管T7的导通/关闭状态始终是相反的,因此可以通过改变晶体管选型(P型和N型)的方式来减少一条信号线。例如,将第七晶体管的沟道类型与第四晶体管的沟道类型设置成相反类型,第七晶体管控制端即可采用第二控制信号线Scan2进行控制,不需要设置发光控制信号线。
如图6所示,为本实施例像素电路的一种变形,与图4所示像素电路的不同之处在于,该像素电路的第七晶体管T7为P型晶体管,除第七晶体管T7之外
的所有晶体管均为N型晶体管。第七晶体管T7为P型晶体管,其控制端直接与第二控制信号线Scan2相连。图7所示为该像素电路的时序图,本像素电路只需要Scan1和Scan2两条控制信号线。
本实施例将补偿单元的控制信号线和触控单元的开关控制信号线等兼容到一起,通过信号线复用的方式实现了AMOLED显示和嵌入式光感触控功能的高效整合,提高了产品的附加值。
本实施例提供一种像素电路,如图8所示,与实施例二中图4所示像素电路大致类似,区别之处仅在于,触控单元20中的触控模块22为电容式触控模块,包括:第一晶体管N1和第二电容C2,其中,第一晶体管N1的控制端与第二电容C2的第一端相连,并作为触控模块22的输入端与初始化模块21(第二晶体管N2)相连,第一晶体管N1的第二端作为触控模块22的输出端,与输出控制模块23相连,第一晶体管N1的第一端与公共电压输入端Vcom相连。
本实施例像素电路工作时序图见图5所示,与实施例二相同,其工作原理及过程也与图4所示像素电路大致相同,为简便起见,此处仅简述其工作过程。
在第1阶段,从图5时序1中可以看出,Scan1拉高,触控单元20中的N2导通,N3断开,此阶段数据信号输入,将第二电容C2的第一端与N1控制端重置,为下一阶段信号采集做准备。对显示单元10而言,时序图中的时序1为充电阶段,此时T6、T7导通,T4断开,工作电压Vdd通过T6开始对a点进行充电,a点电位保持为Vdd。
在第2阶段,从图5时序2中可以看到,对触控单元20而言,第二控制信号线Scan2拉高,N3导通,当手指触控到探测电极D时(C2的上极板),直接导致n1节点(N1的控制端)电势降低,如图10所示,此时n1节点电势降低到Vdata-Vf,其中,Vf为由于触摸导致的电势降低,n1节点电势虽然会降低,但是依然使N1的栅源电压满足导通条件,即Vdata-Vf>Vth1;电流通过N1和N3,最终被读取线Read Line接收,此时接收到的信号相比未触摸时电流会有所降低,从而识别出触控点。图10示出第二电容C2的上极板节点n1和下极板节点n0的电势变化。
对显示单元10而言,此时T4导通,T6、T7断开,数据信号线Data上的信号Vdata会通过M5对a点进行重新充电,a点电势由原来的工作电压Vdd变为Vth1+Vdata,即补偿过的数据信号写入第一电容C1,为下一阶段做准备,此时a点电势Va=Vth1+Vdata。
在第3阶段,对触控单元20而言,从图5时序3中可以看到,第一、第二控制信号线Scan1和Scan2均拉低,因此该阶段N1~N3都断开,处于不工作的停滞状态(或者说关闭状态),这个过程对应显示单元10的发光过程,因此其对显示单元10的影响最小。流过发光元件11的电流为IOLED=K(Vdata–VOLED)2,与M2阈值电压无关。
本实施例提供一种内嵌电容式触控显示模块的像素结构设计,像素中包含AMOLED显示补偿电路的同时,还增加了电容式触控单元,不仅能够补偿驱动晶体管阈值电压漂移,提高OLED显示面板亮度的均匀性,同时还在不增加电路结构和操作复杂性的情况下,将触控模块集成于像素电路中,达到简化操作以及制造流程的目的。
可替换地,上述像素电路中的所有晶体管N1、N2、N3、T4、T6、T7、M2、M5均具有相同的沟道类型例如N型,统一晶体管工艺制程,有助于提高产品良率。制备时可采用低温多晶硅(Low Temperature Poly-silicon,LTPS)技术同步完成,进一步简化制备流程,提高产品良率。
在本公开的实施例中,所述各晶体管可以均为N型薄膜晶体管,但对于本领域普通技术人员来讲,在不付出创造性劳动的前提下,对各晶体管的选型变化及因选型变化产生的连接变动,也在本公开的保护范围之内。
与实施例一相类似,本实施例像素电路也存在一种变形,如图9所示,将该像素电路的第七晶体管T7设置为P型晶体管,除第七晶体管T7之外的所有晶体管均设置为N型晶体管,这时可以将第七晶体管T7的控制端直接与第二控制信号线Scan2相连,不需要设置发光控制信号EM,可以省去一条控制信号线。该像素电路的时序图见图7所示。
本公开的实施例提供一种内置有电容式触控模块的像素结构设计,显示单元采用5T1C(5个薄膜晶体管1个电容)的设计,可以解决像素点驱动晶体管由于工艺制程及长时间的操作造成阈值电压(Vth)不一致的问题,使流过每个像素点的电流不受阈值电压的影响,最终保证图像显示的均匀性;本实施例的像素结构设计还可保证整个过程除发光阶段外无电流通过发光元件(OLED),间接提高发光元件的使用寿命。
在不增加电路结构和操作复杂性的情况下,本实施例将补偿电路的控制信号线、数据信号线Data和电容式触控单元的控制信号线、初始化信号线等,通过信号线复用的方式实现了发光显示和电容式触控功能的高效整合,达到
简化操作以及制造流程的目的。
本公开的实施例还提供一种显示装置,设置有实施例一至三中所描述的任一一像素电路。所述显示装置可以为:电子纸、OLED面板、手机、平板电脑、电视机、显示器、笔记本电脑、数码相框、导航仪等任何具有显示功能的产品或部件。
本实施例所述显示装置将触控功能引入显示装置的显示区域,同时实现了发光显示以及触控功能。例如,触控模块一般采用在显示区域像素中周期性植入的方式设置。如图11所示,每一个内置有触控模块的像素电路200即为一个触控点,触控模块22的周期性分布方式、分布密度或者间距可以根据实际情况(如触控点的设计要求)进行设计,本实施例对此不作限定。其余像素采用只具有显示单元的像素电路100。
本公开的实施例显示装置,亮度均匀性好,同时在不增加电路结构和操作复杂性的情况下,在像素电路中集成有用以实现触控功能的模块,可以达到简化操作以及制造流程的目的。
本公开的实施例所述的技术特征,在不冲突的情况下,可任意相互组合使用。
为了便于清楚说明,在本公开中采用了第一、第二等字样对相似项进行类别区分,该第一、第二字样并不在数量上对本公开进行限制,只是对一种优选的方式的举例说明,本领域技术人员根据本公开所公开的内容,想到的显而易见的相似变形或相关扩展均属于本公开的保护范围内。
本说明书中的各个实施例均采用递进的方式描述,各个实施例之间相同相似的部分互相参见即可,每个实施例重点说明的都是与其他实施例的不同之处。尤其,对于方法实施例而言,描述得比较简单,相关之处参见设备实施例的部分说明即可。
本领域普通技术人员可以理解实现上述实施例方法中的全部或部分流程,是可以通过计算机程序来指令相关的硬件来完成,所述的程序可存储于一计算机可读取存储介质中,该程序在执行时,可包括如上述各方法的实施例的流程。其中,所述的存储介质可为磁碟、光盘、只读存储记忆体(Read-Only Memory,ROM)或随机存储记忆体(Random Access Memory,RAM)等。
以上所述,仅为本公开的具体实施方式,但本公开的保护范围并不局限于此,任何熟悉本技术领域的技术人员在本公开揭露的技术范围内,可轻易
想到的变化或替换,都应涵盖在本公开的保护范围之内。因此,本公开的保护范围应该以权利要求的保护范围为准。
本申请要求于2014年8月26日递交的中国专利申请第201410425976.3号的优先权,在此全文引用上述中国专利申请公开的内容以作为本申请的一部分。
Claims (13)
- 一种像素电路,包括:显示单元和触控单元,所述显示单元包括:发光元件、驱动晶体管、存储电容、电源开关模块、预充模块和补偿模块,其中,所述预充模块用于对所述驱动晶体管的控制端充电,并在所述存储电容的作用下保持,以使得所述补偿模块到存储电容之间保持导通的状态;所述补偿模块用于对数据信号进行补偿并将补偿的数据信号写入所述存储电容;所述电源开关模块用于在数据信号写入所述存储电容后,将工作电压输入所述驱动晶体管;所述驱动晶体管利用存储在所述存储电容中的数据信号驱动所述发光元件发光;所述触控单元包括:初始化模块、触控模块和输出控制模块,其中,所述初始化模块用于在所述预充模块工作的同时,对所述触控模块进行初始化;所述触控模块用于对相应区域内的触控信号进行采集;所述输出控制模块用于在所述补偿模块工作的同时开启输出通路,将所述触控模块采集到的触控信号输出。
- 根据权利要求1所述的像素电路,所述发光元件的一端与接地端相连,另一端与所述驱动晶体管的第二端相连;所述驱动晶体管的第一端连接所述电源开关模块的第二端,控制端连接所述存储电容的第一端;所述电源开关模块的第一端连接工作电压输入端,控制端输入发光控制信号;所述存储电容的第二端与所述接地端相连;所述预充模块与所述电源开关模块的第二端、所述驱动晶体管的控制端以及第一控制信号线相连;所述补偿模块与数据信号线、所述驱动晶体管的控制端以及第二控制信号线相连。
- 根据权利要求2所述的像素电路,其中所述初始化模块与所述触控模块的输入端相连,并连接所述第一控制信号线、初始化信号线;所述输出控制模块与所述触控模块的输出端相连,并连接所述第二控制信号线和信号读取线。
- 根据权利要求1-3中任一项所述的像素电路,其中所述触控模块为光感式触控模块,或者电容式触控模块。
- 根据权利要求1-4中任一项所述的像素电路,其中所述触控模块包括感光管和第一电容,其中,所述感光管的第一端与所述感光管的控制端,以及所述第一电容的第一端相连,并作为所述触控模块的输入端与所述初始化模块相连,所述感光管的第二端与所述第一电容的第二端相连,并作为所述触控模块的输出端与所述输出控制模块相连。
- 根据权利要求1-4中任一项所述的像素电路,其中所述触控模块包括第一晶体管和第二电容,其中,所述第一晶体管的控制端与所述第二电容的第一端相连,并作为所述触控模块的输入端与所述初始化模块相连,所述第一晶体管的第二端作为所述触控模块的输出端,与所述输出控制模块相连,所述第一晶体管的第一端、所述第二电容的第二端均与公共电压输入端相连。
- 根据权利要求1-6中任一项所述的像素电路,其中所述初始化模块为第二晶体管,所述输出控制模块为第三晶体管。
- 根据权利要求1-7中任一项所述的像素电路,其中所述补偿模块包括第四晶体管和第五晶体管,所述第四晶体管的第一端与所述数据信号线相连,第二端与所述第五晶体管的第一端相连,控制端与所述第二控制信号线相连;所述第五晶体管的第二端与所述第五晶体管的控制端相连,并连接所述驱动晶体管的控制端。
- 根据权利要求1-8中任一项所述的像素电路,其中所述预充模块为第六晶体管,所述电源开关模块为第七晶体管。
- 根据权利要求9所述的像素电路,其中所有所述晶体管均具有相同的沟道类型。
- 根据权利要求9所述的像素电路,其中所述第七晶体管的沟道类型与所述第四晶体管的沟道类型相反,所述第七晶体管的控制端与所述第二控制信号线相连。
- 一种显示装置,设置有权利要求1-11任一项所述的像素电路。
- 一种像素电路的驱动方法,包括:预充模块对驱动晶体管的控制端充电,使该控制端的电位变为工作电压,并在所述存储电容的作用下保持,以使得所述补偿模块到存储电容之间保持导通的状态,同时触控单元中的初始化模块对触控模块进行初始化;补偿模块对数据信号进行补偿并将补偿过的数据信号加载到所述驱动晶体管的控制端,并写入所述存储电容,同时触控单元中的输出控制模块 开启输出通路,将所述触控单元采集到的触控信号输出至信号读取线;关闭所述触控单元,同时电源开关模块开启,工作电压输入所述驱动晶体管,所述驱动晶体管利用存储在所述存储电容中的数据信号驱动所述发光元件发光。
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