WO2019205750A1 - 像素电路的检测方法、显示面板的驱动方法和显示面板 - Google Patents

像素电路的检测方法、显示面板的驱动方法和显示面板 Download PDF

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Publication number
WO2019205750A1
WO2019205750A1 PCT/CN2019/071804 CN2019071804W WO2019205750A1 WO 2019205750 A1 WO2019205750 A1 WO 2019205750A1 CN 2019071804 W CN2019071804 W CN 2019071804W WO 2019205750 A1 WO2019205750 A1 WO 2019205750A1
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Prior art keywords
voltage
driving transistor
transistor
sensing
pixel circuit
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PCT/CN2019/071804
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English (en)
French (fr)
Inventor
宋丹娜
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京东方科技集团股份有限公司
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Priority to US16/469,375 priority Critical patent/US11308875B2/en
Publication of WO2019205750A1 publication Critical patent/WO2019205750A1/zh

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    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • 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
    • 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
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • 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
    • 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
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • 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]
    • G09G3/3275—Details of drivers for data electrodes
    • G09G3/3291—Details of drivers for data electrodes in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/04—Structural and physical details of display devices
    • G09G2300/0421—Structural details of the set of electrodes
    • G09G2300/0426—Layout of electrodes and connections
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0842—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor
    • G09G2300/0852—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor being a dynamic memory with more than one capacitor
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0264—Details of driving circuits
    • G09G2310/0278—Details of driving circuits arranged to drive both scan and data electrodes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • 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

  • Embodiments of the present disclosure relate to a method of detecting a pixel circuit, a method of driving a display panel, and a display panel.
  • the Organic Light Emitting Diode (OLED) display device has the characteristics of wide viewing angle, high contrast, and fast response. Moreover, the organic light emitting diode display device has an advantage of higher luminance, lower driving voltage, and the like than the inorganic light emitting display device. Due to the above characteristics and advantages, organic light emitting diode (OLED) display devices have been receiving widespread attention and can be applied to devices having display functions such as mobile phones, displays, notebook computers, digital cameras, instrumentation, and the like.
  • At least one embodiment of the present disclosure provides a method of detecting a pixel circuit, the pixel circuit including a driving transistor including a gate and a first pole, the first pole of the driving transistor being coupled to a sensing line
  • the detecting method includes: applying a reference data voltage to a gate of the driving transistor to charge the sensing line through a first pole of the driving transistor during a reference charging period, and applying the reference data voltage a first time period after which a reference voltage is obtained from the sensing line; in a data charging period, a detection data voltage different from the reference data voltage is applied to a gate of the driving transistor to pass the first of the driving transistor
  • the sensing line is charged, and an initial sensing voltage is obtained from the sensing line at the first duration after the detection data voltage is applied.
  • a sensing voltage of the pixel circuit is obtained based on at least the reference voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage.
  • the reference data voltage is zero.
  • a sensing voltage of the pixel circuit is equal to a difference between the initial sensing voltage and the reference voltage.
  • a predetermined gap is set between adjacent display frames; and the reference charging period and the data charging period are both in the same predetermined gap.
  • the reference charging period is before the data charging period.
  • the detecting method provided by an embodiment of the present disclosure further includes: applying a reference data voltage to a gate of the driving transistor to supplement the sensing by a first pole of the driving transistor during a supplementary reference charging period Line charging, obtaining a supplemental reference voltage from the sensing line at the first duration after applying the reference data voltage; wherein the reference charging period, the supplemental reference charging period, and the data charging period are both In the same predetermined gap, and the supplemental reference charging period is after the data charging period; and obtaining a sensing voltage of the pixel circuit based on the reference voltage, the supplemental reference voltage, and the initial sensing voltage .
  • a sensing voltage of the pixel circuit is equal to a difference between the initial sensing voltage and an average value of the reference voltage and the supplementary reference voltage.
  • the pixel circuit further includes a first transistor and a storage capacitor, and the first pole and the second pole of the first transistor are respectively connected to the signal line and the driving transistor a gate connection, a first end and a second end of the storage capacitor are respectively connected to a gate of the driving transistor and a first electrode of the driving transistor;
  • the detecting method further comprises: in the reference charging cycle Opening the first transistor to continuously apply the reference data voltage to a gate of the driving transistor for a period of time before the initial sensing voltage is obtained; and in the data charging period, opening the The first transistor is continually applied to the gate of the driving transistor for a period of time before the initial sensing voltage is obtained.
  • the pixel circuit further includes a second transistor, a first pole of the second transistor is coupled to a first pole of the driving transistor, and the second transistor is A second pole is coupled to the sense line; the detecting method further includes turning off the first transistor and the second transistor before obtaining the initial sense voltage.
  • the pixel circuit further includes a first transistor and a storage capacitor, and the first pole and the second pole of the first transistor are respectively connected to the signal line and the driving transistor a gate connection, a first end and a second end of the storage capacitor are respectively connected to a gate of the driving transistor and a first electrode of the driving transistor;
  • the detecting method further comprises: in the data charging cycle Turning off the first transistor after applying the detection data voltage to a gate of the driving transistor, and re-turning on the first transistor before obtaining the initial sensing voltage; and during the closing of the first transistor And a voltage supplied from the signal line to a gate of the driving transistor is converted from the detected data voltage to a second detected data voltage having a voltage value smaller than the detected data voltage.
  • the second detected data voltage is zero.
  • the second pole of the driving transistor is coupled to the first power voltage terminal to receive the first power voltage.
  • At least one embodiment of the present disclosure also provides a driving method of a display panel including a pixel circuit and a sensing line, the pixel circuit including a driving transistor, the driving transistor including a gate and a first pole,
  • the sensing line is coupled to the first electrode of the driving transistor
  • the driving method includes: applying a reference data voltage to a gate of the driving transistor to pass a first pole of the driving transistor in a reference charging period Charging the sensing line, obtaining a reference voltage from the sensing line at a first duration after applying the reference data voltage; applying a different threshold to the gate of the driving transistor during a data charging period
  • a detection data voltage of the data voltage charges the sensing line through a first pole of the driving transistor, and an initial sensing voltage is obtained from the sensing line at the first duration after the detecting data voltage is applied
  • a sensing voltage of the pixel circuit is obtained based on at least the reference voltage and the initial sensing voltage
  • the driving crystal is obtained based on the sensing voltage
  • the driving method provided by an embodiment of the present disclosure further includes: establishing a compensation amount of the sub-pixel unit including the pixel circuit according to the obtained threshold voltage.
  • the driving method provided by an embodiment of the present disclosure further includes: performing a compensation operation on the sub-pixel unit by using the compensation amount during a display operation of the display panel.
  • At least one embodiment of the present disclosure further provides a display panel including a pixel circuit, a sensing line, and a control circuit.
  • the pixel circuit includes a driving transistor including a gate and a first electrode, the sensing line is coupled to a first electrode of the driving transistor, and the control circuit is configured to perform a detecting method of a pixel circuit as follows Or the display panel drive method:
  • the sensing voltage of the pixel circuit is obtained based on at least the reference voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage.
  • 1A is a schematic diagram of a pixel circuit
  • 1B is a schematic diagram of another pixel circuit
  • 1C is a schematic diagram of still another pixel circuit
  • 1D is a driving timing diagram for acquiring a reference sensing voltage and an off sensing voltage during shutdown
  • 1E is a driving timing chart for detecting a threshold voltage of a driving transistor during power-on
  • 1F is a driving timing diagram of a reference sensing voltage of a driving transistor that acquires a plurality of pixel circuits during shutdown;
  • FIG. 2 is an exemplary flowchart of a method of detecting a pixel circuit provided by at least one embodiment of the present disclosure
  • 3A is a schematic diagram of a pixel circuit
  • 3B is a schematic diagram of another pixel circuit
  • 4A is a driving timing chart of the pixel circuit shown in FIG. 3B;
  • 4B is another timing chart of driving of the pixel circuit shown in FIG. 3B;
  • FIG. 5 is a timing chart of still another driving of the pixel circuit shown in FIG. 3B;
  • FIG. 6 is an exemplary flowchart of a driving method of a display panel provided by at least one embodiment of the present disclosure
  • FIG. 7A is a schematic diagram of a display panel provided by at least one embodiment of the present disclosure.
  • FIG. 7B is a schematic diagram of a display panel (including sub-pixel units) provided by at least one embodiment of the present disclosure.
  • the sub-pixel unit in the organic light emitting diode (OLED) display panel is generally in a matrix driving manner. Depending on whether or not a switching component is introduced in each sub-pixel unit, the OLED display panel can be classified into an active matrix driving type and a passive matrix driving type.
  • the AMOLED (ie, active matrix driven OLED) display panel integrates a set of thin film transistors and storage capacitors in the pixel circuits of each sub-pixel unit, and through the driving control of the thin film transistors and the storage capacitors, the convection can be realized. The current of the OLED is controlled so that the OLED emits light as needed.
  • the basic pixel circuit used by the sub-pixel unit in the AMOLED display panel is usually a 2T1C pixel circuit, that is, a basic function of driving the OLED illumination by using two thin film transistors (TFTs) and one storage capacitor Cst.
  • 1A and 1B are schematic views showing two 2T1C pixel circuits, respectively.
  • a 2T1C pixel circuit includes a switching transistor T0, a driving transistor N0, and a storage capacitor Cst.
  • the gate of the switching transistor T0 is connected to the scan line to receive the scan signal Sca1; for example, the source of the switching transistor T0 is connected to the signal line to receive the data signal Vdata; the drain of the switching transistor T0 is connected to the driving transistor N0.
  • the 2T1C pixel circuit uses two TFTs and a storage capacitor Cst to control the light and dark (grayscale) of the pixel.
  • the data signal Vdata fed through the signal line by the data driving circuit charges the storage capacitor Cst via the switching transistor T0, thereby storing the data signal Vdata in the storage capacitor Cst.
  • the stored data signal Vdata controls the degree of conduction of the driving transistor N0, thereby controlling the magnitude of the current flowing through the driving transistor to drive the OLED to emit light, and the value of this current determines the gray level of the pixel illumination.
  • the switching transistor T0 is an N-type transistor and the driving transistor N0 is a P-type transistor.
  • another 2T1C pixel circuit also includes a switching transistor T0, a driving transistor N0, and a storage capacitor Cst, but the connection mode thereof is slightly changed, and the driving transistor N0 is an N-type transistor.
  • the variation of the pixel circuit of FIG. 1B with respect to FIG. 1A includes that the positive terminal of the OLED is connected to the first voltage terminal to receive the first voltage Vdd (high voltage), and the negative terminal is connected to the drain of the driving transistor N0, and the driving transistor The source of N0 is connected to the second voltage terminal to receive the second voltage Vss (low voltage, such as ground voltage).
  • the operation mode of the 2T1C pixel circuit is basically the same as that of the pixel circuit shown in FIG. 1A, and details are not described herein again.
  • the switching transistor T0 is not limited to an N-type transistor, and may be a P-type transistor. In this case, the polarity of the scan signal Sca1 that controls its on or off is changed accordingly. can.
  • the OLED display panel typically includes a plurality of sub-pixel units arranged in an array, each of which may include, for example, the above-described pixel circuits.
  • the threshold voltage of the driving transistor in the pixel circuit of each sub-pixel unit may be different due to the fabrication process, and the threshold voltage of the driving transistor may be drifted due to, for example, the influence of temperature variation. Therefore, the difference in the threshold voltage of each of the driving transistors may cause display failure (e.g., display unevenness), so it is necessary to compensate the threshold voltage of the driving transistor.
  • FIG. 1C shows a pixel circuit design (ie, a 3T1C circuit) that can detect a threshold voltage of a driving transistor in a pixel circuit
  • the driving transistor N0 is an N-type transistor.
  • the sensing transistor S0, the sensing line SEN, the detecting circuit SAMP, the analog-to-digital converter ADC (not shown), and the like are introduced on the basis of the 2T1C circuit.
  • the first end of the sensing transistor S0 may be connected to the source of the driving transistor N0 (an example of the sensed first pole), and the second end of the sensing transistor S0 is connected to the detecting circuit SAMP via the sensing line,
  • the control terminal of the sensing transistor S0 can receive the scan signal Sca2.
  • the parasitic capacitance Cp and the parasitic resistance Rp are present on the sensing line SEN.
  • the driving transistor N0 is turned on, after a data signal (eg, data voltage) Vdata is applied to the gate of the driving transistor N0 via the switching transistor T0, the driving transistor N0 is turned on under the control of the data signal Vdata, thereby being The sensing line SEN is charged via the source of the driving transistor N0 and the sensing transistor S0 such that the source potential of the driving transistor N0 changes.
  • a data signal eg, data voltage
  • the reference threshold voltage Vth' and/or the parameter K of the drive transistor of the pixel circuit can be obtained during shutdown and the obtained reference threshold voltage Vth' and/or parameter K can be used for detection during the power-on display phase (eg , real-time detection) the threshold voltage Vth of the driving transistor.
  • the threshold voltage Vth' of the driving transistor is detected in the power-on display phase using the reference threshold voltage Vth' of the driving transistor of the pixel circuit obtained in the shutdown display phase, with reference to Figs. 1C - 1F.
  • a voltage Vdr may be applied to the gate of the driving transistor during shutdown, and before the driving transistor is turned off (for example, at time t1) and after the driving transistor is turned off (for example, at time t2), respectively, at the driving transistor.
  • the reference threshold voltage Vth', the voltage Vdr, and the reference sensing voltage Vsr may be stored in a memory such as an OLED and used to detect the threshold voltage Vth of the driving transistor in the power-on display phase.
  • the above describes a method of detecting a reference sensing voltage, a cut-off sensing voltage, and a reference threshold voltage of a driving transistor of a single pixel circuit during shutdown, and specifically detecting a plurality of pixel circuits during shutdown (eg, display) in conjunction with FIG. 1F
  • a method of reference sensing voltage of a driving transistor of a four-row sub-pixel unit of a panel is described.
  • the scan signal Sca1_1 and the scan signal Sca2_1 may be respectively applied to the control terminals of the switching transistor and the sensing transistor located in the first row, respectively, and are acquired at a predetermined time after the application of the scan signals Sca1_1 and Sca2_1.
  • the reference sensing voltage Vsr_1 of the driving transistor of one row; then the scanning signal Sca1_2 and the scanning signal Sca2_2 may be respectively applied to the control terminals of the switching transistor and the sensing transistor located in the second row, and predetermined after the application of the scanning signals Sca1_2 and Sca2_2
  • the time length acquires the reference sensing voltage Vsr_2 of the driving transistor located in the second row; then the scanning signal Sca1_3 and the scanning signal Sca2_3 may be respectively applied to the control terminals of the switching transistor and the sensing transistor located in the third row, and the scanning signal Sca1_3 is applied and The predetermined duration after Sca2_3 acquires the reference sensing voltage Vsr_3 of the driving transistor located in the third row; further, the scanning signal Sca1_4 and the scanning signal Sca2_4 may be respectively applied to the control terminals of the switching transistor and the sensing transistor located in the fourth row, and The predetermined length of time after the application of the scanning signals Sca1
  • the analog-to-digital converter ADC can convert the analog voltage signal acquired by the detection circuit SAMP into a digital signal, for example, dat1, dat2, dat3, and dat4 of the ADC output (dat4 is not shown) corresponding to Vsr_1, Vsr_2, and Vsr_3, respectively. And Vsr_4.
  • FIG. 1F only shows a method of acquiring the reference sensing voltages Vsr_1 to Vsr_4 of the driving transistors located in the first to fourth rows after a predetermined period of time after the application of the scanning signal, however, at the present line
  • the off-sensing voltage for example, Vb_1 to Vb_4
  • the reference threshold voltage of the driving transistor can be obtained (for example, Vth_1' to Vth_4) ').
  • the switching transistors and the sensing transistors in the pixel circuits of the sub-pixel units of the other rows may be turned on row by row, and the corresponding reference sensing voltages and cutoffs are obtained.
  • the sensing voltage and the reference threshold voltage are not described herein.
  • the reference threshold voltage Vth′ and the parameter K of the driving transistor of the pixel circuit of the sub-pixel unit may also be obtained during shutdown, and used to detect the threshold voltage of the driving transistor during the power-on display phase.
  • I is the saturation current of the driving transistor
  • Vgs is the gate-source voltage of the driving transistor
  • detecting the threshold voltage of the driving transistor during the power-on display phase may include the following step S510.
  • Step S510 applying a first data voltage Vd1 (Vd1 is equal to Vdr) to the gate of the driving transistor during the power-on period (for example, a time gap of the adjacent display frame), and a predetermined length of time after the first data voltage Vd1 is applied (for example, T1-t0) acquires the first sensing voltage Vs1 at the first pole of the driving transistor, and determines whether the first sensing voltage Vs1 is equal to the reference sensing voltage Vsr.
  • Vd1 is equal to Vdr
  • the detecting method of the threshold voltage of the driving transistor may further include the following step S520.
  • Step S520 applying a second data voltage Vd2 different from the first data voltage Vd1 to the gate of the driving transistor during the power-on period, and a predetermined duration (eg, t1-t0) after the application of the second data voltage Vd2 is at the driving transistor
  • the first pole acquires the second sensing voltage Vs2 and determines whether the second sensing voltage Vs2 is equal to the reference sensing voltage Vsr.
  • the detecting method of the threshold voltage of the driving transistor may further include the following step S530.
  • Step S530 Step S520 is repeated until the second sensing voltage Vs2 is equal to the reference sensing voltage Vsr.
  • the inventor has noticed that the value of the sensing voltage obtained during the startup is affected by the display content, that is, the sensing voltage obtained by the detection includes an environmental noise component, and thus, the threshold voltage of the driving transistor obtained by the above method is used. It is possible to deviate from the true value, which in turn reduces the brightness uniformity of the display panel and the display device including the pixel circuit.
  • the detection of the threshold voltage during the turn-on of the drive transistor typically involves detecting the sense voltage (eg, the first sense voltage Vs1 and the second sense voltage Vs2) multiple times at different times, and thus, The values of the environmental noise components included in the sensing voltage detected at the time may be different from each other, thereby not only increasing the absolute value of the difference between the threshold voltage and the true value of the driving transistor obtained by the above method, but also prolonging The time required for the successive approximation (i.e., the number of times the step S520 is performed) is increased, which in turn increases the time for driving the transistor threshold detection and reduces the brightness uniformity of the display panel and the display device including the pixel circuit.
  • Embodiments of the present disclosure provide a method for detecting a pixel circuit, a display panel, and a driving method thereof, which can remove ambient noise in an initial sensing voltage, thereby improving a threshold compensation effect of the pixel circuit. Further, the brightness uniformity of the display panel including the pixel circuit and the display device can be improved.
  • At least one embodiment of the present disclosure provides a method for detecting a pixel circuit.
  • the pixel circuit includes a driving transistor.
  • the driving transistor includes a gate and a first electrode.
  • the first pole of the driving transistor is coupled to the sensing line
  • the detecting method includes: Applying a reference data voltage to a gate of the driving transistor to charge the sensing line through the first pole of the driving transistor at a reference charging period, obtaining a reference voltage from the sensing line at a first duration after applying the reference data voltage; a charging period, applying a detection data voltage different from the reference data voltage to the gate of the driving transistor to charge the sensing line through the first pole of the driving transistor, and obtaining an initial from the sensing line at a first time after the detection data voltage is applied Sense voltage.
  • a sensing voltage of the pixel circuit is obtained based on at least the reference voltage and the initial sensing voltage, and a threshold voltage of the driving transistor is obtained based on the sensing voltage.
  • the detection method of the pixel circuit of the embodiment of the present disclosure can eliminate the adverse effect of ambient noise on the threshold voltage detection of the driving transistor.
  • the detection method of the pixel circuit according to the embodiment of the present disclosure is described below by way of a few examples, and as described below, different features in these specific examples may be combined with each other without conflicting with each other, thereby obtaining The new examples, these new examples are also within the scope of the disclosure.
  • the display panel may be an organic light emitting diode display panel or other types of display panels, etc., and the embodiment of the present disclosure is not limited thereto.
  • the following is an example of an organic light emitting diode display panel.
  • the detection method of the pixel circuit can be used to detect the threshold voltage Vth of the driving transistor T3 of the pixel circuit.
  • the detection method can be implemented at least partially in software and loaded and executed by a processor in the display panel, or at least partially implemented in hardware or firmware to remove ambient noise in the initial sense voltage, boosting the pixel.
  • the threshold compensation effect of the circuit For example, the detection method of the pixel circuit provided by the embodiment of the present disclosure will be exemplarily described below with reference to the pixel circuit illustrated in FIGS. 3A and 3B, but the embodiment of the present disclosure is not limited thereto.
  • the pixel circuit includes a driving transistor T3, a light emitting element EL coupled to a first electrode of the driving transistor, and a sensing line SEN.
  • the driving transistor T3 includes a gate, a first pole and a second pole. The first pole is connected to the light emitting element, and the second pole is coupled to the first power voltage terminal VDD.
  • the driving transistor is used in the pixel circuit to control the flow of the light emitting element EL.
  • the illuminating current is coupled to the first pole of the driving transistor.
  • the sensing circuit can obtain the reference voltage and the initial sensing voltage at different times through the sensing line SEN.
  • the one end of the illuminating element EL and the driving transistor are One pole is connected, and the other end is connected to the second power voltage terminal VSS.
  • the pixel circuit can apply the reference data voltage and the detection data voltage to the gate of the driving transistor T3 at different timings. According to actual application requirements, the pixel circuit can also apply a set voltage (for example, 0V) to the driving transistor T3.
  • a pole e.g., source
  • the light emitting element EL is an organic light emitting diode (OLED), and embodiments of the present disclosure do not limit the specific structure, the color of the light, the material used, and the like.
  • the pixel circuit may further include a first transistor T1 and a storage capacitor Cst; the first transistor T1 serves as an input write switch, and the gate of the first transistor T1 serves as a control terminal G1 and a switch scan line (in the figure) Connected to receive a scan signal, the first pole of the first transistor T1 and the second pole of the first transistor T1 are respectively coupled to the signal line Vdat and the gate of the drive transistor T3 to receive data signals, respectively (eg, reference) Data voltage or detection data voltage) and applying the received data signal to the gate of the driving transistor T3; the first end and the second end of the storage capacitor Cst are respectively connected to the gate of the driving transistor T3 and the first electrode of the driving transistor T3 , thereby storing the received data signal.
  • the first transistor T1 serves as an input write switch
  • the gate of the first transistor T1 serves as a control terminal G1 and a switch scan line (in the figure)
  • the pixel circuit further includes a second transistor T2.
  • the second transistor T2 acts as a sensing switch, the first pole of the second transistor T2 is connected to the first pole of the driving transistor T3, and the second pole of the second transistor T2 is connected to the sensing line SEN for allowing when conducting Charging the sensing line to form a sensing voltage, and detecting the reference voltage and the initial sensing voltage through the sensing line at different times; the gate of the second transistor T2 serves as the control terminal G2 and the sensing scan line ( Connected to receive a sense control signal.
  • the pixel circuit shown in FIG. 3A can be equivalent to the pixel circuit shown in FIG. 3B.
  • the parasitic capacitance Cvc can be charged by the current from the driving transistor T1, so that the voltage on the corresponding sensing line SEN changes.
  • embodiments of the present disclosure are not limited thereto, and in addition to using the parasitic capacitance Cvc on the sensing line SEN, one end may be separately provided to be connected to the sensing line SEN and the other end may be connected to a fixed voltage (eg, ground), for example. Capacitance is sensed to assist in implementing the detection method of an embodiment of the present disclosure.
  • one end of the sensing line SEN is also connected to a detecting circuit that acquires a voltage (for example, a reference voltage) on the sensing line SEN at a specific time (for example, time t1) based on the sampling signal.
  • the output of the detection circuit is connected to an analog-to-digital converter ADC (not shown in FIGS. 3A and 3B), and the analog signal outputted by the detection circuit is sent to the digital converter ADC, and thus a corresponding Digital signal for subsequent processing.
  • the output end of the detection circuit is also connected to the amplification circuit, and the analog signal outputted by the detection circuit is amplified and sent to the digital converter ADC.
  • the driving transistor T3 is an N-type transistor
  • the first power supply voltage terminal VDD is a high voltage terminal (eg, providing a high level)
  • the second power supply voltage terminal VSS is a low voltage terminal ( For example, a low level is provided, which is lower than a high level of the aforementioned high voltage terminal, such as ground.
  • the first extreme source of the driving transistor T3 is connected to the light emitting element EL; the second extreme drain of the driving transistor T3 is connected to the first power supply voltage terminal VDD to receive the first power supply voltage.
  • the first transistor T1 and the second transistor T2 are also N-type transistors, but embodiments of the present disclosure are not limited thereto.
  • the first transistor T1 and/or the second transistor T2 may be P-type transistors, and accordingly, the polarity of the control signals applied to the gates of the first transistor T1 and the second transistor T2 may be changed.
  • the driving transistor T3 may also be a P-type transistor, and the source (first pole) of the P-type driving transistor may still be coupled to the sensing line to perform a detecting operation.
  • the method for detecting a pixel circuit includes the following steps.
  • Step S10 applying a reference data voltage to the gate of the driving transistor to charge the sensing line through the first pole of the driving transistor during the reference charging period, and obtaining the reference voltage from the sensing line for the first time after the reference data voltage is applied .
  • Step S20 applying a detection data voltage different from the reference data voltage to the gate of the driving transistor to charge the sensing line through the first pole of the driving transistor during the data charging period, the first duration after applying the detection data voltage, from The sense line obtains an initial sense voltage.
  • each sensing voltage detecting operation may include step S10 and step S20, but embodiments of the present disclosure are not limited thereto; and, for example, according to actual application requirements It is also possible to make only the sensing voltage detection of the later stage of the successive approximation process including step S10 and step S20, so that the sensing voltage detection of the initial stage of successive approximation includes only step S20.
  • a high level signal may be applied to the gates of the first transistor T1 and the second transistor T2 at time t0 and the first transistor T1 and the second transistor T2 may be turned on, whereby the signal line Vdat may be
  • the supplied reference data voltage Vre is applied to the gate of the driving transistor T3, so that the driving transistor T3 is turned on, and thus the sensing line SEN can be charged through the first pole of the driving transistor T3; then, after the reference data voltage Vre is applied
  • the first duration ie, t1-t0
  • the reference voltage Vrs is obtained from the sensing line SEN, and the reference voltage Vrs may represent an environmental factor (eg, temperature or/and display content) for the voltage obtained from the sensing line SEN influences.
  • the reference data voltage Vre may be zero (ie, the same as the ground voltage of the entire system), but embodiments of the present disclosure are not limited thereto.
  • the first transistor T1 and the second transistor T2 may be turned off before the reference voltage Vrs is obtained from the sensing line SEN (for example, at time t1), thereby avoiding the detection reference
  • the detection may be performed while the second transistor T2 is still in an on state, and the reference voltage Vrs is obtained from the sensing line SEN.
  • the reference data voltage Vre is continuously applied to the gate of the driving transistor T3, maintaining the gate of the driving transistor T3. Voltage, but embodiments of the present disclosure are not limited thereto.
  • a high level signal may be applied to the gates of the first transistor T1 and the second transistor T2 at time t2 and the first transistor T1 and the second transistor T2 may be turned on again, whereby the signal line may be
  • the detection data voltage Vd provided by Vdat different from the reference data voltage Vre is applied to the gate of the driving transistor T3, so that the driving transistor T3 is turned on, and thus the sensing line SEN can be charged through the first pole of the driving transistor T3;
  • the initial sensing voltage Vri may be obtained from the sensing line SEN at a first duration (ie, t3-t2) after the detection data voltage Vd is applied.
  • T3-t2 may be equal to t1-t0, whereby the reference voltage Vrs may be made closer to the ambient noise component in the initial sense voltage Vri.
  • the detected data voltage Vd may be the same as the data voltage applied in a conventional sensing voltage detecting operation.
  • the first transistor T1 and the second transistor T2 may be turned off before the initial sensing voltage Vri is obtained from the sensing line SEN (for example, at time t3), thereby avoiding The voltage fluctuation on the sense line SEN is detected when the initial sense voltage Vri is detected, which in turn can improve the accuracy of the initial sense voltage Vri value obtained by the detection.
  • the detection may be performed while the second transistor T2 is still in an on state, and the initial sensing voltage Vri is obtained from the sensing line SEN.
  • the detected data voltage Vd may be continuously applied to the gate of the driving transistor T3, maintaining the gate of the driving transistor T3.
  • the voltage on the pole but embodiments of the present disclosure are not limited thereto.
  • the sensing voltage Vs of the pixel circuit can be obtained based on the reference voltage Vrs and the initial sensing voltage Vri.
  • the sensing voltage Vs obtained by the above method removes an environmental noise component (ie, temperature or/and display content) due to environmental factors in the initial sensing voltage Vri (ie, a reference) The voltage Vrs), thereby causing the obtained sensing voltage Vs to remove the environmental noise in the initial sensing voltage, closer to the true value, thereby improving the threshold compensation effect of the pixel circuit and improving the display panel and the display device including the pixel circuit Brightness uniformity.
  • an environmental noise component ie, temperature or/and display content
  • the voltage Vrs thereby causing the obtained sensing voltage Vs to remove the environmental noise in the initial sensing voltage, closer to the true value, thereby improving the threshold compensation effect of the pixel circuit and improving the display panel and the display device including the pixel circuit Brightness uniformity.
  • the first time length may be set according to actual application requirements, and the embodiment of the present disclosure does not specifically limit this.
  • the reference voltage Vrs and the initial sensing voltage Vri may be detected before the driving transistor T3 is completely turned off by setting the first duration, but embodiments of the present disclosure are not limited thereto.
  • the first duration can be made as short as possible, whereby the detection time of the sensing voltage can be lowered, and the detection efficiency can be improved.
  • the voltage variation of the sensing line SEN illustrated in FIG. 4A during charging (eg, from time t0 to time t1) follows a linear variation law, but embodiments of the present disclosure are not limited thereto; for example, according to practical applications It is required that the voltage variation of the sensing line SEN during charging can follow the variation rule that the voltage change rate gradually decreases with time (see, for example, FIG. 1E).
  • the display panel including the pixel circuit may include a plurality of display periods, each of which is used to display one frame of image, and during display of the image, the signal line DAT may be driven to pixel circuits of different sub-pixel units according to actual needs.
  • Different data voltages Vim are applied to the gates of the transistors T3 so that different driving transistors T3 have different conduction levels, thereby causing different light emitting elements EL to have different light emitting luminances, whereby different sub-pixel units display different gray scales.
  • the control circuit of the display panel triggers the display operation using the line sync signal HS and the column sync signal VS.
  • the length of time during which an image of one frame is displayed is equal to the time required to display the first row of sub-pixel units of the frame image to the last row of sub-pixel units displaying the frame image.
  • a predetermined gap time gap
  • a blanking time may be set between adjacent display periods, and the predetermined gap may be at least part of the blank time.
  • both the reference charging period OPr and the data charging period OPd are in the same predetermined gap, thereby avoiding errors caused by changes in environmental factors (for example, electron mobility), thereby improving the accuracy of the detection result.
  • the reference charging period OPr may be located before the data charging period OPd, but embodiments of the present disclosure are not limited thereto, and the reference charging period OPr may also be located after the data charging period OPd according to actual application requirements.
  • the detection method of the pixel circuit provided by the embodiment of the present disclosure includes the following step S30 according to actual application requirements.
  • Step S30 applying a reference data voltage to the gate of the driving crystal to charge the sensing line through the first pole of the driving transistor during the supplementary reference charging period, and obtaining the supplement from the sensing line for the first time after the reference data voltage is applied.
  • the reference voltage The reference voltage.
  • a high level signal may be applied to the gates of the first transistor T1 and the second transistor T2 at time t4 and the first transistor T1 and the second transistor T2 may be led.
  • the reference data voltage Vre provided by the signal line Vdat can be applied to the gate of the driving transistor T3, so that the driving transistor T3 is turned on, and the sensing line SEN can be charged through the first pole of the driving transistor T3;
  • the supplemental reference voltage Vrss may be obtained from the sense line SEN at a first duration (ie, t5-t4) after the reference data voltage Vre is applied;
  • the supplemental reference voltage Vrss may represent an environmental factor (eg, temperature or/and display content) The influence of ambient noise factors on the voltage obtained from the sense line SEN.
  • the sensing voltage Vs of the pixel circuit may be obtained based on the reference voltage Vrs, the complementary reference voltage Vrss, and the initial sensing voltage Vri; the sensing voltage Vs of the pixel circuit may be equal to, for example, the initial sensing voltage Vri and the reference voltage Vrs and the supplemental reference voltage
  • T5-t4 may be equal to t3-t2 and t1-t0, whereby the supplemental reference voltage Vrss may be made closer to the ambient noise component in the initial sense voltage Vri, but embodiments of the present disclosure are not limited thereto.
  • the sensing voltage Vs is improved by subtracting the mean value of the two in the initial sensing voltage Vri, that is, subtracting the influence of the environmental noise on the voltage. The accuracy.
  • the influence of environmental factors on the voltage obtained from the sensing line SEN can be measured multiple times at different times, whereby a more accurate ambient noise component can be obtained, which in turn can be obtained.
  • the voltage Vs is closer to the true value.
  • the reference charging period OPr, the supplemental reference charging period OPs, and the data charging period OPd may all be in the same predetermined gap, and the supplementary reference charging period Ops may be located after the data charging period OPd, but embodiments of the present disclosure are not limited thereto.
  • the obtained sensing voltage Vs can be made close even in the case where the environmental factor fluctuates in the data charging period.
  • the true value thereby improving the threshold compensation effect of the pixel circuit and improving the brightness uniformity of the display panel and the display device including the pixel circuit.
  • the time lengths of the reference charging period OPr, the supplemental reference charging period OPs, and the data charging period OPd are respectively greater than the on-times of the first transistor T1 and the first transistor T1 in the corresponding charging period.
  • the time lengths of the reference charging period OPr, the supplementary reference charging period OPs, and the data charging period OPd may not be equal.
  • the data charging period OPd may be greater than the time length of the reference charging period OPr and the time of supplementing the reference charging period Ops.
  • the length but the embodiment of the present disclosure is not limited thereto; for example, the time lengths of the reference charging period OPr, the supplementary reference charging period OPs, and the data charging period OPd may also be equal.
  • the flow of the detection method for the pixel circuit may include more or less operations, which may be performed sequentially or in parallel.
  • the flow of the detection method described above includes a plurality of operations occurring in a specific order, it should be clearly understood that the order of the plurality of operations is not limited.
  • the detection method described above may be performed once or multiple times according to predetermined conditions.
  • FIG. 5 shows still another driving timing chart of the pixel circuit shown in FIG. 3B, and the timing chart shown in FIG. 5 is similar to the driving timing chart shown in FIG. 4A.
  • FIG. 5 only shows The driving timing chart of the pixel circuit in the data charging period OPd, the driving timing chart in the reference charging period OPr can be drawn with reference to the timing charts shown in FIG. 5 and FIG. 4A, and details are not described herein again.
  • the first transistor T1 is turned off after the detection data voltage Vd is applied to the gate of the driving transistor T3, and then the first transistor is turned on before the initial sensing voltage Vri is obtained.
  • the driving transistor T3 is in an off state, and the voltage of the first electrode of the driving transistor T3 is no longer changed.
  • the second detected data voltage Vd is zero, but embodiments of the present disclosure are not limited thereto.
  • the voltage on the gate of the driving transistor T3 is the second detected data voltage Vd after the first transistor T1 is turned back on
  • the difference between the second detected data voltage Vd and the voltage on the first pole of the driving transistor T3 ( That is, Vgs) is smaller than the threshold voltage of the driving transistor T3, so that the driving transistor T3 is turned off, at which time the voltage on the first electrode of the driving transistor T3 and the voltage on the sensing line SEN will no longer increase, and thus the initial sensing voltage Vri is detected.
  • At least one embodiment of the present disclosure further provides a driving method of a display panel, the sub-pixel unit of the display panel includes a pixel circuit and a sensing line, the pixel circuit includes a driving transistor, and the driving transistor includes a gate and a first pole, and the sensing The line is connected to the first pole of the driving transistor, and the driving method comprises: performing the detecting method provided by any one of the embodiments of the present disclosure on the pixel circuit to obtain a threshold voltage of the driving transistor of the pixel circuit.
  • the display panel includes a plurality of sub-pixel units, each of which may include a pixel circuit.
  • the sub-pixel units included in the display panel may be arranged in an array, for example, and the pixel circuits may be arranged in an array, for example, and the light emitted by the light-emitting elements of the different sub-pixel units may be different in color, whereby the display panel can realize color display.
  • the pixel circuit included in the display panel may be the pixel circuit shown in FIG. 3A or 3B.
  • the driving method of the display panel provided by this embodiment includes step S210.
  • Step S210 Perform a detection method of the pixel circuit provided by any embodiment of the present disclosure on the pixel circuit to obtain a threshold voltage of a driving transistor of the pixel circuit.
  • the detection method of the pixel circuit can be referred to the embodiment shown in FIG. 2, and details are not described herein again.
  • the driving method of the display panel provided in this embodiment further includes step S220 and step S230 according to actual application requirements.
  • Step S220 Establish a compensation amount of the sub-pixel unit including the pixel circuit according to the obtained threshold voltage.
  • Step S230 During the display operation of the display panel, the compensation operation is performed on the sub-pixel unit by using the compensation amount.
  • the threshold voltages of the driving transistors of the pixel circuits of the sub-pixel units may be detected line by line, and the detection result is stored, and then, the driving transistors of the pixel circuits of all the sub-pixel units of the display panel are acquired.
  • a compensation amount may be established for each sub-pixel unit including the pixel circuit; finally, during the display operation of the display panel, a corresponding threshold compensation operation is performed on each sub-pixel unit of the display panel based on the established compensation amount. This allows one cycle of threshold compensation to be completed.
  • These compensation quantities can be saved in the form of a look-up table and stored in the memory of the drive unit for easy recall or update.
  • the detection method of the pixel circuit may be performed on the pixel circuit of the sub-pixel unit located in the first row, and the threshold voltage of the driving transistor of the pixel circuit of the sub-pixel unit located in the first row may be acquired.
  • the detection method of the pixel circuit may be performed on the pixel circuit of the sub-pixel unit located in the second row, and the threshold voltage of the driving transistor of the pixel circuit of the sub-pixel unit located in the second row may be acquired; Then, the pixel circuits of the sub-pixel units of the display panel in other rows may be detected line by line until the threshold voltages of the driving transistors of the pixel circuits of all the sub-pixel units of the display panel are acquired; finally, for each pixel circuit including the pixel circuit The sub-pixel unit establishes a compensation amount, and performs a threshold compensation operation on the sub-pixel unit of the display panel based on the compensation amounts in a subsequent display operation.
  • the driving method of the display panel provided by the embodiment may remove the ambient noise component in the initial sensing voltage, thereby making the obtained sensing voltage and the threshold voltage of the driving transistor closer to a true value, thereby improving the application.
  • At least one embodiment of the present disclosure further provides a display panel including a pixel circuit, a sensing line, and a control circuit, the pixel circuit including a driving transistor including a gate and a first pole, the sensing line
  • the control circuit is configured to perform the detection method provided by any embodiment of the present disclosure or the driving method of the display panel provided by any one of the embodiments of the present disclosure.
  • the display panel 10 includes a pixel circuit and a control circuit 120.
  • the pixel circuit can be, for example, the pixel circuit shown in FIG. 3A or FIG. 3B.
  • the pixel circuit in the display panel of the present embodiment is implemented as an example of the pixel circuit shown in FIG. 3A.
  • the display panel provided in this embodiment is specifically described, but the embodiment of the present disclosure is not limited thereto.
  • FIG. 7A shows a schematic diagram of a display panel provided by an embodiment of the present disclosure.
  • the display panel includes a sub-pixel unit P, a sensing line SEN (eg, SEN1, SEN2, SEN3, etc.), and a scan line (eg, G1-1, G1-2, G2-).
  • SEN sensing line
  • G1-1, G1-2, G2- scan line
  • data lines for example, D1, D2, D3, etc.
  • gate drive circuit 110 control circuit 120
  • data drive circuit 130 data drive circuit 130
  • detection circuit 140 detection circuit
  • the scan lines G1-1, G2-1, and G3-1 are respectively connected to the control terminal G1 of the first transistor of the pixel circuit of the sub-pixel unit P located in the first row, the second row, and the third row, and the scanning line G1- 2.
  • G2-2 and G3-2 are respectively connected to the control terminal G2 of the second transistor of the pixel circuit of the sub-pixel unit located in the first row, the second row, and the third row.
  • the sub-pixel unit in the display area of the display panel includes the pixel circuit P, and the peripheral area setting control circuit 120 of the display panel outside the display area, the pixel circuit includes a driving transistor,
  • the driving transistor includes a gate and a first electrode, and the sensing line SEN is connected to the first electrode of the driving transistor.
  • the control circuit 120 is configured to perform the detection method provided by any embodiment of the present disclosure or the driving method of the display panel provided by any of the embodiments of the present disclosure.
  • the specific implementation manner of the detection method in this embodiment can be referred to the embodiment shown in FIG. 2, and details are not described herein again.
  • control circuit 120 is also configured to control the gate drive circuit 110, the data drive circuit 130, and the detection circuit 140.
  • the data driving circuit 130 is configured to provide a reference data voltage and a detected data voltage at different times according to actual application requirements.
  • the gate driving circuit 110 is configured to provide scan signals of the first transistor and the second transistor, thereby controlling on and off of the first transistor and the second transistor.
  • the pixel circuit is further configured to receive the reference data voltage and the sense data voltage and apply the reference data voltage and the sense data voltage to the gate of the drive transistor at different times.
  • the detection circuit 140 is configured to read the reference voltage and the initial sense voltage from the sense line SEN.
  • the pixel circuit further includes a second switching transistor T2, and the light emitting element EL may be, for example, an organic light emitting diode, but embodiments of the present disclosure are not limited thereto.
  • the second pole and the first pole of the driving transistor may be configured to be respectively connected to the first power voltage terminal VDD and the first pole of the light emitting element EL, and the second pole of the light emitting element EL is connected to the second power voltage terminal VSS.
  • the first pole of the second switching transistor T2 is electrically connected to the first pole of the driving transistor, and the second pole of the second switching transistor T2 is electrically connected to the detecting circuit 140.
  • the pixel circuit further includes a sensing line SEN that electrically connects the second pole of the second switching transistor T2 to the detecting circuit 140.
  • the pixel circuit further includes a first transistor T1 configured to acquire a data signal from the data driving circuit 130, a data signal to be written to the gate of the driving transistor, and a storage capacitor Cst to store the data signal.
  • the pixel circuit may further include a signal line Vdat, and the first electrode of the first transistor T1 is connected to the signal line Vdat.
  • controller circuit 120 is a timing controller (T-CON).
  • the control circuit 120 may further include a processor (not shown) and a memory (not shown), the memory including executable code and data required to run the code or generated data, the processor The executable code is executed to perform the detection method provided by any embodiment of the present disclosure or the driving method of the display panel provided by any of the embodiments of the present disclosure.
  • the processor is, for example, a central processing unit (CPU) or other form of processing unit having data processing capabilities and/or instruction execution capabilities, for example, the processor can be implemented as a general purpose processor, and is also a microcontroller, microprocessor , digital signal processor, dedicated image processing chip, or field programmable logic array.
  • the memory may include, for example, volatile memory and/or non-volatile memory, and may include, for example, a read only memory (ROM), a hard disk, a flash memory, or the like. Accordingly, the memory can be implemented as one or more computer program products, which can include various forms of computer readable storage media, on which one or more executables can be stored Code (for example, computer program instructions).
  • the processor can execute the program instruction to perform the detection method provided by any embodiment of the present disclosure, thereby obtaining the threshold voltage of the driving transistor of the pixel circuit included in the display panel, thereby implementing the threshold compensation function of the display panel.
  • the memory can also store various other applications and various data, such as an initial threshold voltage for each pixel circuit, and various data used and/or generated by the application, and the like.
  • the display panel provided in this embodiment can remove the ambient noise component in the initial sensing voltage, thereby making the obtained sensing voltage and the threshold voltage of the driving transistor closer to the true value, thereby improving the compensation effect of the display panel. And brightness uniformity.

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Abstract

一种像素电路的检测方法以及显示面板(10)及其驱动方法。像素电路包括驱动晶体管(T3)，驱动晶体管(T3)包括栅极和第一极，驱动晶体管(T3)的第一极与感测线(SEN)耦接。检测方法包括：在参考充电周期(OPr)，向驱动晶体管(T3)的栅极施加参考数据电压(Vre)，在施加参考数据电压(Vre)后的第一时长(t1-t0)，从感测线(SEN)获得基准电压(Vrs)(S10)；在数据充电周期(OPd)，向驱动晶体管(T3)的栅极施加不同于参考数据电压(Vre)的检测数据电压(Vd)，在施加检测数据电压(Vd)后的第一时长(t3-t2)，从感测线(SEN)获得初始感测电压(Vri)(S20)。至少基于基准电压(Vre)和初始感测电压(Vri)获得像素电路的感测电压(Vs)，并基于感测电压(Vs)获得驱动晶体管的阈值电压(Vth)。像素电路的检测方法可以消除环境噪声对于驱动晶体管(T3)的阈值电压(Vth)检测的不利影响。

Description

像素电路的检测方法、显示面板的驱动方法和显示面板
本申请要求于2018年4月26日递交的中国专利申请第201810386462.X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。
技术领域
本公开的实施例涉及一种像素电路的检测方法、显示面板的驱动方法和显示面板。
背景技术
有机发光二极管(Organic Light Emitting Diode，OLED)显示器件具有视角宽、对比度高、响应速度快等特点。并且，相比于无机发光显示器件，有机发光二极管显示器件具有更高的发光亮度、更低的驱动电压等优势。由于具有上述特点和优势，有机发光二极管(OLED)显示器件逐渐受到人们的广泛关注并且可以适用于手机、显示器、笔记本电脑、数码相机、仪器仪表等具有显示功能的装置。
发明内容
本公开的至少一个实施例提供了一种像素电路的检测方法，所述像素电路包括驱动晶体管，所述驱动晶体管包括栅极和第一极，所述驱动晶体管的第一极与感测线耦接，所述检测方法包括：在参考充电周期，向所述驱动晶体管的栅极施加参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的第一时长，从所述感测线获得基准电压；在数据充电周期，向所述驱动晶体管的栅极施加不同于所述参考数据电压的检测数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述检测数据电压后的所述第一时长，从所述感测线获得初始感测电压。至少基于所述基准电压和所述初始感测电压获得所述像素电路的感测电压，并基于所述感测电压获得所述驱动晶体管的阈值电压。
例如，在本公开一实施例提供的检测方法中，所述参考数据电压为零。
例如，在本公开一实施例提供的检测方法中，所述像素电路的感测电压等于所述初始感测电压与所述基准电压的差值。
例如，在本公开一实施例提供的检测方法中，在相邻显示帧之间设置预定间隙；以及所述参考充电周期和所述数据充电周期均在同一个预定间隙中。
例如，在本公开一实施例提供的检测方法中，所述参考充电周期位于所述数据充电周期之前。
例如，本公开一实施例提供的检测方法，还包括：在补充参考充电周期，向所述驱动晶体管的栅极施加所述参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的所述第一时长，从所述感测线获得补充基准电压；其中，所述参考充电周期、所述补充参考充电周期和所述数据充电周期均在同一个预定间隙中，且所述补充参考充电周期位于所述数据充电周期之后；以及基于所述基准电压、所述补充基准电压和所述初始感测电压获得所述像素电路的感测电压。
例如，在本公开一实施例提供的检测方法中，所述像素电路的感测电压等于所述初始感测电压与所述基准电压和所述补充基准电压的平均值的差值。
例如，在本公开一实施例提供的检测方法中，所述像素电路还包括第一晶体管和存储电容，所述第一晶体管的第一极和第二极分别与信号线和所述驱动晶体管的栅极连接，所述存储电容的第一端和第二端分别与所述驱动晶体管的栅极和所述驱动晶体管的第一极连接；所述检测方法还包括：在所述参考充电周期中，打开所述第一晶体管，以在获得所述初始感测电压之前的时间段，将所述参考数据电压持续施加到所述驱动晶体管的栅极；以及在所述数据充电周期中，打开所述第一晶体管，以在获得所述初始感测电压之前的时间段，将所述检测数据电压持续施加到所述驱动晶体管的栅极。
例如，在本公开一实施例提供的检测方法中，所述像素电路还包括第二晶体管，所述第二晶体管的第一极与所述驱动晶体管的第一极连接，所述第二晶体管的第二极连接至所述感测线；所述检测方法还包括：在获得所述初始感测电压之前关闭所述第一晶体管和所述第二晶体管。
例如，在本公开一实施例提供的检测方法中，所述像素电路还包括第一 晶体管和存储电容，所述第一晶体管的第一极和第二极分别与信号线和所述驱动晶体管的栅极连接，所述存储电容的第一端和第二端分别与所述驱动晶体管的栅极和所述驱动晶体管的第一极连接；所述检测方法还包括：在所述数据充电周期中，向所述驱动晶体管的栅极施加所述检测数据电压之后关闭所述第一晶体管，并在获得所述初始感测电压之前重新打开所述第一晶体管；以及在所述第一晶体管关闭期间，所述信号线向所述驱动晶体管的栅极提供的电压由所述检测数据电压转变为电压值小于所述检测数据电压的第二检测数据电压。
例如，在本公开一实施例提供的检测方法中，所述第二检测数据电压为零。
例如，在本公开一实施例提供的检测方法中，所述驱动晶体管的第二极与第一电源电压端耦接以接收第一电源电压。
本公开的至少一个实施例还提供了一种显示面板的驱动方法，所述显示面板包括像素电路和感测线，所述像素电路包括驱动晶体管，所述驱动晶体管包括栅极和第一极，所述感测线与所述驱动晶体管的第一极耦接，所述驱动方法包括：在参考充电周期，向所述驱动晶体管的栅极施加参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的第一时长，从所述感测线获得基准电压；在数据充电周期，向所述驱动晶体管的栅极施加不同于所述参考数据电压的检测数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述检测数据电压后的所述第一时长，从所述感测线获得初始感测电压；其中，至少基于所述基准电压和所述初始感测电压获得所述像素电路的感测电压，并基于所述感测电压获得所述驱动晶体管的阈值电压。
例如，本公开一实施例提供的驱动方法，还包括：根据所获得的所述阈值电压建立包括所述像素电路的子像素单元的补偿量。
例如，本公开一实施例提供的驱动方法，还包括：在所述显示面板的显示操作期间，采用所述补偿量对所述子像素单元进行补偿操作。
本公开的至少一个实施例又提供了一种显示面板，该显示面板包括像素电路、感测线和控制电路。所述像素电路包括驱动晶体管，所述驱动晶体管包括栅极和第一极，所述感测线与所述驱动晶体管的第一极耦接；所述控制 电路配置为执行如下像素电路的检测方法或显示面板的驱动方法：
在参考充电周期，向所述驱动晶体管的栅极施加参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的第一时长，从所述感测线获得基准电压；
在数据充电周期，向所述驱动晶体管的栅极施加不同于所述参考数据电压的检测数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述检测数据电压后的所述第一时长，从所述感测线获得初始感测电压；
其中，至少基于所述基准电压和所述初始感测电压获得所述像素电路的感测电压，并基于所述感测电压获得所述驱动晶体管的阈值电压。
附图说明
为了更清楚地说明本公开实施例的技术方案，下面将对实施例的附图作简单地介绍，显而易见地，下面描述中的附图仅仅涉及本公开的一些实施例，而非对本公开的限制。
图1A是一种像素电路的示意图；
图1B是另一种像素电路的示意图；
图1C是再一种像素电路的示意图；
图1D是在关机期间获取参考感测电压和截止感测电压的驱动时序图；
图1E是在开机期间检测驱动晶体管的阈值电压的驱动时序图；
图1F是在关机期间获取多个像素电路的驱动晶体管的参考感测电压的驱动时序图；
图2是本公开至少一个实施例提供的像素电路的检测方法的示例性流程图；
图3A是一种像素电路的示意图；
图3B是另一种像素电路的示意图；
图4A是图3B是示出的像素电路的一种驱动时序图；
图4B是图3B是示出的像素电路的另一种驱动时序图；
图5是图3B是示出的像素电路的再一种驱动时序图；
图6是本公开至少一个实施例提供的显示面板的驱动方法的示例性流程图；
图7A是本公开至少一个实施例提供的显示面板的示意图；以及
图7B是本公开至少一个实施例提供的显示面板(包括子像素单元)的示意图。
具体实施方式
下面将结合附图，对本公开实施例中的技术方案进行清楚、完整地描述参考在附图中示出并在以下描述中详述的非限制性示例实施例，更加全面地说明本公开的示例实施例和它们的多种特征及有利细节。应注意的是，图中示出的特征不是必须按照比例绘制。本公开省略了已知材料、组件和工艺技术的描述，从而不使本公开的示例实施例模糊。所给出的示例仅旨在有利于理解本公开示例实施例的实施，以及进一步使本领域技术人员能够实施示例实施例。因而，这些示例不应被理解为对本公开的实施例的范围的限制。
除非另外特别定义，本公开使用的技术术语或者科学术语应当为本公开所属领域内具有一般技能的人士所理解的通常意义。本公开中使用的“第一”、“第二”以及类似的词语并不表示任何顺序、数量或者重要性，而只是用来区分不同的组成部分。此外，在本公开各个实施例中，相同或类似的参考标号表示相同或类似的构件。
有机发光二极管(OLED)显示面板中的子像素单元一般采用矩阵驱动方式。根据每个子像素单元中是否引入开关元器件，OLED显示面板可分为有源矩阵(Active Matrix)驱动式和无源矩阵(Passive Matrix)驱动式。AMOLED(也即，有源矩阵驱动式OLED)显示面板在每一个子像素单元的像素电路中都集成了一组薄膜晶体管和存储电容，通过对薄膜晶体管和存储电容的驱动控制，可以实现对流过OLED的电流的控制，从而使OLED根据需要发光。
AMOLED显示面板中的子像素单元使用的基础像素电路通常为2T1C像素电路，即利用两个薄膜晶体管(Thin-film transistor，TFT)和一个存储电容Cst来实现驱动OLED发光的基本功能。图1A和图1B分别为示出了两种2T1C像素电路的示意图。
如图1A所示，一种2T1C像素电路包括开关晶体管T0、驱动晶体管N0以及存储电容Cst。例如，该开关晶体管T0的栅极连接扫描线以接收扫描信 号Sca1；例如，该开关晶体管T0的源极连接到信号线以接收数据信号Vdata；该开关晶体管T0的漏极连接到驱动晶体管N0的栅极；驱动晶体管N0的源极连接到第一电压端以接收第一电压Vdd(高电压)，驱动晶体管N0的漏极连接到OLED的正极端；存储电容Cst的一端连接到开关晶体管T0的漏极以及驱动晶体管N0的栅极，另一端连接到驱动晶体管N0的源极以及第一电压端；OLED的负极端连接到第二电压端以接收第二电压Vss(低电压，例如接地电压)。该2T1C像素电路使用两个TFT和存储电容Cst来控制像素的明暗(灰阶)。当通过扫描线施加扫描信号Sca1以开启开关晶体管T0时，数据驱动电路通过信号线送入的数据信号Vdata将经由开关晶体管T0对存储电容Cst充电，由此将数据信号Vdata存储在存储电容Cst中，且此存储的数据信号Vdata控制驱动晶体管N0的导通程度，由此控制流过驱动晶体管以驱动OLED发光的电流大小，此电流的数值决定该像素发光的灰阶。在图1A所示的2T1C像素电路中，开关晶体管T0为N型晶体管而驱动晶体管N0为P型晶体管。
如图1B所示，另一种2T1C像素电路也包括开关晶体管T0、驱动晶体管N0以及存储电容Cst，但是其连接方式略有改变，且驱动晶体管N0为N型晶体管。图1B的像素电路相对于图1A的变化之处包括：OLED的正极端连接到第一电压端以接收第一电压Vdd(高电压)，而负极端连接到驱动晶体管N0的漏极，驱动晶体管N0的源极连接到第二电压端以接收第二电压Vss(低电压，例如接地电压)。存储电容Cst的一端连接到开关晶体管T0的漏极以及驱动晶体管N0的栅极，另一端连接到驱动晶体管N0的源极以及第二电压端。该2T1C像素电路的工作方式基本上与图1A所示的像素电路基本相同，这里不再赘述。
此外，对于图1A和图1B所示的像素电路，开关晶体管T0不限于N型晶体管，也可以为P型晶体管，此时控制其导通或截止的扫描信号Sca1的极性进行相应地改变即可。
OLED显示面板通常包括多个按阵列排布的子像素单元，每个子像素单元例如可以包括上述像素电路。在OLED显示面板中，各个子像素单元的像素电路中的驱动晶体管的阈值电压由于制备工艺可能存在差异，而且由于例如温度变化的影响，驱动晶体管的阈值电压可能会产生漂移现象。因此，各 个驱动晶体管的阈值电压的不同可能会导致显示不良(例如显示不均匀)，所以就需要对驱动晶体管的阈值电压进行补偿。
例如，图1C示出了一种可以检测像素电路中驱动晶体管的阈值电压的像素电路设计(也即，3T1C电路)，驱动晶体管N0为N型晶体管。例如，如图1C所示，为了实现补偿功能，在2T1C电路的基础上引入感测晶体管S0、感测线SEN、检测电路SAMP、模数转换器ADC(图中未示出)等。例如，可以将感测晶体管S0的第一端连接到驱动晶体管N0的源极(被感测的第一极的示例)，感测晶体管S0的第二端经由感测线与检测电路SAMP连接，感测晶体管S0的控制端可以接收扫描信号Sca2。例如，感测线SEN上存在寄生电容Cp和寄生电阻Rp。
例如，当驱动晶体管N0导通之后，在经由开关晶体管T0向驱动晶体管N0的栅极施加数据信号(例如，数据电压)Vdata之后，驱动晶体管N0在数据信号Vdata的控制下导通，由此可以经由驱动晶体管N0的源极以及感测晶体管S0对感测线SEN充电，使得驱动晶体管N0的源极电位改变。当驱动晶体管N0的源极的电压Vs等于驱动晶体管N0的栅极电压Vg与驱动晶体管的阈值电压Vth的差值时(即Vg-Vs-Vth＝Vgs-Vth＝0)，驱动晶体管N0将会截止，充电过程结束，此时可以通过感测线SEN获得该电压Vs，并基于该电压Vs以及数据电压Vdata获得阈值电压Vth。
发明人注意到，可以在关机期间获得像素电路的驱动晶体管的参考阈值电压Vth’和/或参数K，并将获得的参考阈值电压Vth’和/或参数K用于在开机显示阶段检测(例如，实时检测)驱动晶体管的阈值电压Vth。下面将结合图1C-图1F对使用在关机显示阶段获得的像素电路的驱动晶体管的参考阈值电压Vth’，在开机显示阶段检测驱动晶体管的阈值电压Vth做示例性说明。
例如，如图1D所示，可以在关机期间向驱动晶体管的栅极施加电压Vdr，并在驱动晶体管截止之前(例如，t1时刻)和驱动晶体管截止之后(例如，t2时刻)，分别在驱动晶体管的第一极获取参考感测电压Vsr和截止感测电压Vb，由此可以获得像素电路的参考阈值电压Vth’，也即，Vth’＝Vdr-Vb。之后，可以将参考阈值电压Vth’、电压Vdr和参考感测电压Vsr存储在例如OLED的存储器中，并将其用于在开机显示阶段检测驱动晶体管的阈值电压Vth中。
例如，以上阐述了在关机期间检测单个像素电路的驱动晶体管的参考感测电压、截止感测电压和参考阈值电压的方法，下面结合图1F具体阐述在关机期间检测多个像素电路(例如，显示面板的四行子像素单元)的驱动晶体管的参考感测电压的方法。
例如，如图1F所示，可以首先向位于第一行的开关晶体管和感测晶体管的控制端分别施加扫描信号Sca1_1和扫描信号Sca2_1，并在施加扫描信号Sca1_1和Sca2_1后的预定时长获取位于第一行的驱动晶体管的参考感测电压Vsr_1；然后可以向位于第二行的开关晶体管和感测晶体管的控制端分别施加扫描信号Sca1_2和扫描信号Sca2_2，并在施加扫描信号Sca1_2和Sca2_2后的预定时长获取位于第二行的驱动晶体管的参考感测电压Vsr_2；接着可以向位于第三行的开关晶体管和感测晶体管的控制端分别施加扫描信号Sca1_3和扫描信号Sca2_3，并在施加扫描信号Sca1_3和Sca2_3后的预定时长获取位于第三行的驱动晶体管的参考感测电压Vsr_3；进一步地，可以向位于第四行的开关晶体管和感测晶体管的控制端分别施加扫描信号Sca1_4和扫描信号Sca2_4，并在施加扫描信号Sca1_4和Sca2_4后的预定时长获取位于第四行的驱动晶体管的参考感测电压Vsr_4。例如，模数转换器ADC可以将检测电路SAMP获取的模拟电压信号转换为数字信号，例如，ADC输出的dat1、dat2、dat3和dat4(图中未示出dat4)分别对应于Vsr_1、Vsr_2、Vsr_3和Vsr_4。
例如，为了清楚起见，图1F仅示出了在施加扫描信号后的预定时长获取位于第一行-第四行的驱动晶体管的参考感测电压Vsr_1至Vsr_4的方法，然而，在位于本行的驱动晶体管饱和之后，在打开下一行的开关晶体管和感测晶体管之前，还可以获取截止感测电压(例如，Vb_1至Vb_4)，由此可以获得驱动晶体管的参考阈值电压(例如，Vth_1’至Vth_4’)。
例如，在显示面板包含更多行的子像素单元的情况下，可以逐行打开位于其它行的子像素单元的像素电路中的开关晶体管和感测晶体管，并获取对应的参考感测电压、截止感测电压和参考阈值电压，具体方法在此不再赘述。
需要说明的是，根据实际应用需求，还可以在关机期间获得子像素单元的像素电路的驱动晶体管的参考阈值电压Vth’和参数K，并在开机显示阶段将其用于检测驱动晶体管的阈值电压Vth，此处，K＝I/(Vgs-Vth) 2，I为驱 动晶体管的饱和电流，Vgs为驱动晶体管的栅源电压，具体方法在此不再赘述。
例如，如图1E所示，在开机显示阶段检测驱动晶体管的阈值电压可以包括以下的步骤S510。
步骤S510：在开机期间(例如，相邻显示帧的时间间隙)向驱动晶体管的栅极施加第一数据电压Vd1(Vd1等于Vdr)，并在施加第一数据电压Vd1后的预定时长(例如，t1-t0)在驱动晶体管的第一极获取第一感测电压Vs1，并判断第一感测电压Vs1是否等于参考感测电压Vsr。
例如，如果第一感测电压Vs1等于参考感测电压Vsr，那么驱动晶体管的Vth等于参考阈值电压Vth’。例如，如图1E所示，如果第一感测电压Vs1不等于参考感测电压Vsr，驱动晶体管的阈值电压的检测方法还可以包括以下的步骤S520。
步骤S520：在开机期间，向驱动晶体管的栅极施加不同于第一数据电压Vd1的第二数据电压Vd2，在施加第二数据电压Vd2后的预定时长(例如，t1-t0)在驱动晶体管的第一极获取第二感测电压Vs2，并判断第二感测电压Vs2是否等于参考感测电压Vsr。
例如，如果第二感测电压Vs2等于参考感测电压Vsr，那么驱动晶体管的Vth等于参考阈值电压Vth’加上第二数据电压Vd2与参考数据电压Vdr的差值(也即，Vth＝Vth’+Vd2-Vdr)。例如，如图1E所示，如果第二感测电压Vs2不等于参考感测电压Vsr，驱动晶体管的阈值电压的检测方法还可以包括以下的步骤S530。
步骤S530：重复进行步骤S520，直至第二感测电压Vs2等于参考感测电压Vsr。
发明人注意到，在开机期间检测获得的感测电压值会受到显示内容的影响，也即，检测获得的感测电压中包含环境噪声分量，由此，使用上述方法获得的驱动晶体管的阈值电压有可能偏离真实值，进而会降低包括该像素电路的显示面板和显示装置的亮度均匀度。此外，发明人还注意到，驱动晶体管的开机期间的阈值电压的检测通常涉及在不同时刻多次检测感测电压(例如，第一感测电压Vs1和第二感测电压Vs2)，因此，不同时刻检测到的感测电压包含的环境噪声分量的数值可能彼此不同，由此不仅会使得使用上述 方法获得的驱动晶体管的阈值电压与真实值之间的差值的绝对值增大，而且会延长逐次逼近所需的时间(也即，增加执行步骤S520的次数)，进而会延长驱动晶体管阈值检测的时间并降低包括该像素电路的显示面板和显示装置的亮度均匀度。
本公开的实施例提供了一种像素电路的检测方法以及显示面板及其驱动方法，该像素电路的检测方法可以去除初始感测电压中的环境噪声，由此可以提升像素电路的阈值补偿效果，进而可以提升包括该像素电路的显示面板和显示装置的亮度均匀度。
本公开的至少一个实施例提供了一种像素电路的检测方法，像素电路包括驱动晶体管，驱动晶体管包括栅极和第一极，驱动晶体管的第一极与感测线耦接，检测方法包括：在参考充电周期，向驱动晶体管的栅极施加参考数据电压以通过驱动晶体管的第一极对感测线充电，在施加参考数据电压后的第一时长，从感测线获得基准电压；在数据充电周期，向驱动晶体管的栅极施加不同于参考数据电压的检测数据电压以通过驱动晶体管的第一极对感测线充电，在施加检测数据电压后的第一时长，从感测线获得初始感测电压。至少基于基准电压和初始感测电压获得像素电路的感测电压，并基于感测电压获得驱动晶体管的阈值电压。本公开实施例的像素电路的检测方法可以消除环境噪声对于驱动晶体管的阈值电压检测的不利影响。
下面通过几个示例对根据本公开实施例提供的像素电路的检测方法进行非限制性的说明，如下面所描述的，在不相互抵触的情况下这些具体示例中不同特征可以相互组合，从而得到新的示例，这些新的示例也都属于本公开保护的范围。
图2示出了本公开的一个实施例的提供的一种像素电路的检测方法，该像素电路适用于显示面板的子像素单元。例如，该显示面板可以是有机发光二极管显示面板或其他类型的显示面板等，本公开的实施例对此不作限制，下面以有机发光二极管显示面板为例进行介绍。该像素电路的检测方法可用于检测像素电路的驱动晶体管T3的阈值电压Vth。例如，该检测方法可以至少部分以软件的方式实现，并由显示面板中的处理器加载并执行，或至少部分以硬件或固件等方式实现，以去除初始感测电压中的环境噪声，提升像素电路的阈值补偿效果。例如，下面将结合图3A和图3B示出的像素电路对本 公开的实施例提供的像素电路的检测方法做示例性的说明，但本公开的实施例不限于此。
例如，如图3A所示，像素电路包括驱动晶体管T3、与该驱动晶体管的第一极耦接的发光元件EL和感测线SEN。驱动晶体管T3包括栅极、第一极和第二极，第一极连接发光元件，第二极耦接第一电源电压端VDD，该驱动晶体管在像素电路中用于控制流过发光元件EL的发光电流；该感测线SEN与驱动晶体管的第一极耦接，通过该感测线SEN，检测电路可以在不同时刻获取基准电压和初始感测电压；发光元件EL的一端与驱动晶体管的第一极连接，另一端与第二电源电压端VSS连接。该像素电路可以在不同的时刻将参考数据电压和检测数据电压施加在驱动晶体管T3的栅极，根据实际应用需求，该像素电路还可以将设置电压(例如，0V)施加至驱动晶体管T3的第一极(例如源极)，从而控制驱动晶体管T3的状态，例如开启或截止，或流过的驱动电流的大小。例如，发光元件EL为有机发光二极管(OLED)，本公开的实施例对其具体结构、发光颜色、所采用的材料等不作限制。
例如，如图3A所示，像素电路还可以包括第一晶体管T1和存储电容Cst；第一晶体管T1作为输入写入开关，第一晶体管T1的栅极作为控制端G1与开关扫描线(图中未示出)连接以接收扫描信号，第一晶体管T1的第一极和第一晶体管T1的第二极分别与信号线Vdat和驱动晶体管T3的栅极连接，以分别接收数据信号(例如，参考数据电压或检测数据电压)以及将接收的数据信号施加至驱动晶体管T3的栅极；存储电容Cst的第一端和第二端分别与驱动晶体管T3的栅极和驱动晶体管T3的第一极连接，从而存储接收的数据信号。
例如，如图3A所示，像素电路还包括第二晶体管T2。第二晶体管T2作为感测开关，第二晶体管T2的第一极与驱动晶体管T3的第一极连接；第二晶体管T2的第二极与感测线SEN连接，以用于在导通时允许对感测线充电以形成感测电压，且可以在不同时刻通过该感测线实现对基准电压和初始感测电压的检测；第二晶体管T2的栅极作为控制端G2与感测扫描线(图中未示出)连接以接收感测控制信号。
例如，在感测线SEN上有寄生电容Cvc和寄生电阻Rvc的情况下，图3A所示的像素电路可以等效为图3B所示的像素电路。该寄生电容Cvc可以 被来自驱动晶体管T1的电流充电，从而相应的感测线SEN上的电压发生改变。然而，本公开的实施例不限于此，除利用感测线SEN上的寄生电容Cvc之外，也可以单独提供一端与感测线SEN连接而另一端例如与某一固定电压(例如接地)的感测电容，以辅助实现本公开实施例的检测方法。
例如，感测线SEN一端还连接检测电路，检测电路基于采样信号获取特定时刻(例如，t1时刻)的感测线SEN上的电压(例如，基准电压)。例如，根据实际应用需求，检测电路的输出端连接模数转换器ADC(图3A和图3B中未示出)，检测电路输出的模拟信号送入数转换器ADC中，并因此可以获得对应的数字信号，以用于后续处理。例如，根据实际应用需求，检测电路的输出端还连接放大电路，检测电路输出的模拟信号经过放大之后，送入数转换器ADC中。
在上述图3A和图3B示出的实施例中，驱动晶体管T3为N型晶体管，第一电源电压端VDD为高压端(例如，提供高电平)，第二电源电压端VSS为低压端(例如，提供低电平，低于前述高压端的高电平，例如接地)。相应地，驱动晶体管T3的第一极为源极，连接到发光元件EL；驱动晶体管T3的第二极为漏极，连接到第一电源电压端VDD以接收第一电源电压。另外，第一晶体管T1和第二晶体管T2也是N型晶体管，但本公开的实施例不限于此。例如，第一晶体管T1和/或第二晶体管T2可以是P型晶体管，相应地，改变施加至第一晶体管T1和第二晶体管T2的栅极的控制信号的极性即可。又例如，驱动晶体管T3也可以为P型晶体管，仍然可以通过该P型驱动晶体管的源极(第一极)与感测线耦接，以进行检测操作。
例如，如图4A所示，基于图3A或图3B所示的像素电路，本公开的实施例提供的像素电路的检测方法包括以下的步骤。
步骤S10：在参考充电周期，向驱动晶体管的栅极施加参考数据电压以通过驱动晶体管的第一极对感测线充电，在施加参考数据电压后的第一时长，从感测线获得基准电压。
步骤S20：在数据充电周期，向驱动晶体管的栅极施加不同于参考数据电压的检测数据电压以通过驱动晶体管的第一极对感测线充电，在施加检测数据电压后的第一时长，从感测线获得初始感测电压。
例如，检测像素电路的驱动晶体管T3的阈值电压Vth的过程中，每次 感测电压检测操作均可以包括步骤S10和步骤S20，但本公开的实施例不限于此；又例如，根据实际应用需求，还可以仅使得逐次逼近过程的后期阶段的感测电压检测包括步骤S10和步骤S20，而使得逐次逼近的初期阶段的感测电压检测仅包括步骤S20。
例如，在步骤S10中，可以在t0时刻向第一晶体管T1和第二晶体管T2的栅极施加高电平信号并使得第一晶体管T1和第二晶体管T2导通，由此可以将信号线Vdat提供的参考数据电压Vre施加在驱动晶体管T3的栅极上，使得驱动晶体管T3导通，进而可以通过驱动晶体管T3的第一极对感测线SEN充电；然后，可以在施加参考数据电压Vre后的第一时长(也即，t1-t0)，从感测线SEN获得基准电压Vrs，基准电压Vrs可以表示环境因素(例如，温度或/和显示内容)对从感测线SEN获得的电压的影响。例如，参考数据电压Vre可以为零(即与整个系统的接地电压相同)，但本公开的实施例不限于此。
例如，根据实际应用需求，在一个示例中，可以在从感测线SEN获得基准电压Vrs之前(例如，在t1时刻)将第一晶体管T1和第二晶体管T2关闭，由此可以避免在检测基准电压Vrs时感测线SEN上的电压波动，进而可以提升检测获得的基准电压Vrs的准确性。或者，在另一个示例中，可以在第二晶体管T2仍处于开启状态下进行检测，从感测线SEN获得基准电压Vrs。
例如，如图4A所示，在第一晶体管T1打开之后至在获得基准电压Vrs之前的时间段，参考数据电压Vre持续施加到驱动晶体管T3的栅极上，维持驱动晶体管T3的栅极上的电压，但本公开的实施例不限于此。
例如，在步骤S20中，可以在t2时刻向第一晶体管T1和第二晶体管T2的栅极施加高电平信号并使得第一晶体管T1和第二晶体管T2再次导通，由此可以将信号线Vdat提供的不同于参考数据电压Vre的检测数据电压Vd施加在驱动晶体管T3的栅极上，使得驱动晶体管T3导通，进而可以通过驱动晶体管T3的第一极对感测线SEN充电；然后，可以在施加检测数据电压Vd后的第一时长(也即，t3-t2)，从感测线SEN获得初始感测电压Vri。t3-t2可以等于t1-t0，由此可以使得基准电压Vrs与初始感测电压Vri中的环境噪声分量更为接近。例如，检测数据电压Vd可以与常规的感测电压检测操作中施加的数据电压相同。
例如，如图4A所示，在一个示例中，可以在从感测线SEN获得初始感测电压Vri之前(例如，在t3时刻)将第一晶体管T1和第二晶体管T2关闭，由此可以避免在检测初始感测电压Vri时感测线SEN上的电压波动，进而可以提升检测获得的初始感测电压Vri值的准确性。或者，在另一个示例中，可以在第二晶体管T2仍处于开启状态下进行检测，从感测线SEN获得初始感测电压Vri。
例如，如图4A所示，在第一晶体管T1打开之后至在获得初始感测电压Vri之前的时间段，检测数据电压Vd可以持续施加到驱动晶体管T3的栅极上，维持驱动晶体管T3的栅极上的电压，但本公开的实施例不限于此。
然后，可以基于基准电压Vrs和初始感测电压Vri获得像素电路的感测电压Vs。例如，像素电路的感测电压Vs等于初始感测电压Vri与基准电压Vrs的差值，也即，Vs＝Vri-Vrs，但本公开的实施例不限于此。由于基准电压Vrs表示环境噪声分量，所以经上述方法获得的感测电压Vs去除了初始感测电压Vri中因环境因素导致的(例如，温度或/和显示内容)环境噪声分量(也即，基准电压Vrs)，由此使得获得的感测电压Vs去除了初始感测电压中的环境噪声，更接近真实值，进而可以提升像素电路的阈值补偿效果以及提升包括该像素电路的显示面板和显示装置的亮度均匀度。
例如，第一时长可以根据实际应用需求进行设定，本公开的实施例对此不做具体限定。例如，通过设置第一时长可以使得在驱动晶体管T3完全截止之前检测基准电压Vrs和初始感测电压Vri，但本公开的实施例不限于此。例如，在能够获得基本精确的基准电压Vrs和初始感测电压Vri的情况下，可以使得第一时长尽可能地短，由此可以降低感测电压的检测时间，提高检测效率。
需要说明的是，图4A示出的感测线SEN在充电期间(例如，在t0时刻至t1时刻)的电压变化遵从线性变化规律，但本公开的实施例不限于此；例如，根据实际应用需求，感测线SEN在充电期间的电压变化可以遵从下述的变化规律，也即，电压变化率随时间的增长而逐渐降低(例如参见图1E)。
例如，包括该像素电路的显示面板可以包括多个显示周期，每个显示周期用于显示一帧图像，在显示图像期间，信号线DAT可以根据实际需求向不同的子像素单元的像素电路的驱动晶体管T3的栅极施加不同的数据电压 Vim，以使得不同的驱动晶体管T3具有不同的导通程度，进而使得不同的发光元件EL具有不同发光亮度，由此不同的子像素单元显示不同的灰度。为了协调图像显示，显示面板的控制电路使用行同步信号HS和列同步信号VS触发显示操作。
例如，显示一帧图像的时间长度等于显示该帧图像的第一行子像素单元至显示该帧图像的最后一行子像素单元所需的时间。例如，在相邻的显示周期(也即，相邻的显示帧)之间可以设置预定间隙(时间间隙)。例如，相邻的显示周期之间可以设置有空白时间(blanking time),预定间隙可以为空白时间的至少部分时间段。
例如，参考充电周期OPr和数据充电周期OPd均在同一个预定间隙中，由此可以避免环境因素(例如，电子迁移率)变化导致的误差，进而可以提升检测结果的准确性。例如，参考充电周期OPr可以位于数据充电周期OPd之前，但本公开的实施例不限于此，根据实际应用需求，参考充电周期OPr还可以位于数据充电周期OPd之后。
例如，根据实际应用需求，本公开的实施例提供的像素电路的检测方法包括以下的步骤S30。
步骤S30：在补充参考充电周期，向驱动晶体的栅极施加参考数据电压以通过驱动晶体管的第一极对感测线充电，在施加参考数据电压后的第一时长，从感测线获得补充基准电压。
例如，如图4B所示，在补充参考充电周期Ops中，可以在t4时刻向第一晶体管T1和第二晶体管T2的栅极施加高电平信号并使得第一晶体管T1和第二晶体管T2导通，由此可以将信号线Vdat提供的参考数据电压Vre施加在驱动晶体管T3的栅极上，使得驱动晶体管T3导通，进而可以通过驱动晶体管T3的第一极对感测线SEN充电；然后，可以在施加参考数据电压Vre后的第一时长(也即，t5-t4)，从感测线SEN获得补充基准电压Vrss；补充基准电压Vrss可以表示环境因素(例如，温度或/和显示内容等环境噪声因素)对从感测线SEN获得的电压的影响。
之后，可以基于基准电压Vrs、补充基准电压Vrss和初始感测电压Vri获得像素电路的感测电压Vs；像素电路的感测电压Vs例如可以等于初始感测电压Vri与基准电压Vrs和补充基准电压Vrss的平均值的差值，也即，Vs＝ Vri-(Vrs+Vrss)/2。t5-t4可以等于t3-t2以及t1-t0，由此可以使得补充基准电压Vrss与初始感测电压Vri中的环境噪声分量更为接近，但本公开的实施例不限于此。由于该补充基准电压Vrss和基准电压Vrs均表示环境噪声分量，所以通过在初始感测电压Vri中减去二者的均值，即减去了环境噪声对电压的影响，从而提高了感测电压Vs的准确性。
例如，通过设置补充参考充电周期Ops，可以在不同时间多次测量环境因素对从感测线SEN获得的电压的影响，由此可以获得更为精确的环境噪声分量，进而可以使得获得的感测电压Vs更接近真实值。
例如，参考充电周期OPr、补充参考充电周期OPs和数据充电周期OPd可以均在同一个预定间隙中，且补充参考充电周期Ops可以位于数据充电周期OPd之后，但本公开的实施例不限于此。
例如，通过使得参考充电周期OPr和补充参考充电周期Ops位于数据充电周期OPd的两侧，由此即便在环境因素在数据充电周期发生波动的情况下，也可以使得获得的感测电压Vs依然接近真实值，由此可以提升像素电路的阈值补偿效果以及提升包括该像素电路的显示面板和显示装置的亮度均匀度。
例如，如图4A所示，参考充电周期OPr、补充参考充电周期OPs和数据充电周期OPd的时间长度分别大于在对应的充电周期中第一晶体管T1和第一晶体管T1的导通时间。
需要说明的是，参考充电周期OPr、补充参考充电周期OPs和数据充电周期OPd的时间长度可以不相等，例如，数据充电周期OPd可以大于参考充电周期OPr的时间长度和补充参考充电周期Ops的时间长度，但本公开的实施例不限于此；又例如，参考充电周期OPr、补充参考充电周期OPs和数据充电周期OPd的时间长度还可以相等。
另需要说明的是，本公开的实施例中，该用于像素电路的检测方法的流程可以包括更多或更少的操作，这些操作可以顺序执行或并行执行。虽然上文描述的检测方法的流程包括特定顺序出现的多个操作，但是应该清楚地了解，多个操作的顺序并不受限制。上文描述的检测方法可以执行一次，也可以按照预定条件执行多次。
例如，图5示出了图3B示出的像素电路的再一种驱动时序图，图5示 出的时序图与图4A示出的驱动时序图类似，为清楚起见，图5仅示出了像素电路在数据充电周期OPd中的驱动时序图，在参考充电周期OPr中的驱动时序图可以参照图5和图4A示出的时序图绘出，在此不再赘述。
例如，如图5所示，在数据充电周期OPd中，向驱动晶体管T3的栅极施加检测数据电压Vd之后即关闭第一晶体管T1，然后在获得初始感测电压Vri之前重新导通第一晶体管T1；在第一晶体管T1再次导通后，信号线DAT向驱动晶体管T3的栅极提供的电压由检测数据电压Vd转变为电压值小于检测数据电压Vd的第二检测数据电压Vd，由此确保了驱动晶体管T3处于截止状态，并使得驱动晶体管T3的第一极的电压不再变化。例如，第二检测数据电压Vd为零，但本公开的实施例不限于此。
例如，由于在第一晶体管T1重新打开之后，驱动晶体管T3的栅极上的电压为第二检测数据电压Vd，第二检测数据电压Vd与驱动晶体管T3的第一极上的电压的差值(即Vgs)小于驱动晶体管T3的阈值电压，使得驱动晶体管T3截止，此时驱动晶体管T3的第一极上的电压以及感测线SEN上的电压将不再增加，因此在检测初始感测电压Vri时无需关闭第二晶体管T2，由此可以避免第二晶体管T2的下拉效应导致的检测获得初始感测电压Vri偏离其真实值，进而可以使得获得的感测电压Vs更接近真实值。
本公开的至少一个实施例还提供了一种显示面板的驱动方法，显示面板的子像素单元包括像素电路和感测线，像素电路包括驱动晶体管，驱动晶体管包括栅极和第一极，感测线与驱动晶体管的第一极连接，驱动方法包括：对像素电路执行本公开任一实施例提供的检测方法，以获得像素电路的驱动晶体管的阈值电压。
显示面板包括多个子像素单元，每个子像素单元可以包括像素电路。显示面板所包括的子像素单元例如可以排布成阵列，相应地像素电路例如可以排布成阵列，不同的子像素单元的发光元件发出的光的颜色不同，由此显示面板可以实现彩色显示。例如，显示面板所包括的像素电路可以为图3A或图3B所示的像素电路。例如，如图6所示，本实施例提供的显示面板的驱动方法包括步骤S210。
步骤S210：对像素电路执行本公开任一实施例提供的像素电路的检测方法，以获得像素电路的驱动晶体管的阈值电压。
例如，像素电路的检测方法可以参见图2示出的实施例，在此不再赘述。例如，根据实际应用需求，本实施例提供的显示面板的驱动方法还包括步骤S220和步骤S230。
步骤S220：根据所获得的阈值电压建立包括像素电路的子像素单元的补偿量。
步骤S230：在显示面板的显示操作期间，采用补偿量对子像素单元进行补偿操作。
例如，在一个示例中，首先，可以逐行检测这些子像素单元的像素电路的驱动晶体管的阈值电压，并存储检测结果，然后，在获取显示面板的所有子像素单元的像素电路的驱动晶体管的阈值电压之后，可以针对每一个包括像素电路的子像素单元建立补偿量；最后，在显示面板的显示操作期间，基于所建立的补偿量，对显示面板的各子像素单元执行相应的阈值补偿操作；由此可以完成一个周期的阈值补偿。这些补偿量可以查询表的形式保存，存储在驱动装置的存储器之中，以便于调用或更新。
例如，首先可以对位于第一行的子像素单元的像素电路执行本公开任一实施例提供的像素电路的检测方法，并获取位于第一行的子像素单元的像素电路的驱动晶体管的阈值电压；然后可以对位于第二行的子像素单元的像素电路执行本公开任一实施例提供的像素电路的检测方法，并获取位于第二行的子像素单元的像素电路的驱动晶体管的阈值电压；接着，可以对显示面板的位于其它行的子像素单元的像素电路进行逐行检测，直至获取显示面板的所有子像素单元的像素电路的驱动晶体管的阈值电压；最后，针对每一个包括像素电路的子像素单元建立补偿量，并在之后的显示操作中基于这些补偿量对显示面板的子像素单元进行阈值补偿操作。
要说明的是，对于该显示面板的驱动方法的其它的必不可少的步骤可以参见常规的显示面板的驱动方法，这些是本领域的普通技术人员所应该理解的，在此不做赘述。
例如，本实施例提供的显示面板的驱动方法可以去除初始感测电压中的环境噪声分量，由此使得所获得的感测电压和驱动晶体管的阈值电压更接近真实值，由此可以提升应用该驱动方法的显示面板的补偿效果以及亮度均匀度。
本公开的至少一个实施例又提供了一种显示面板，该显示面板包括像素电路、感测线和控制电路，像素电路包括驱动晶体管，该驱动晶体管包括栅极和第一极，该感测线与驱动晶体管的第一极连接；控制电路配置为执行本公开任一实施例提供的检测方法或本公开任一实施例提供的显示面板的驱动方法。
例如，该显示面板10包括像素电路和控制电路120。像素电路例如可以为图3A或图3B所示的像素电路。例如，下面以本实施例的显示面板中的像素电路实现为图3A示出的像素电路为例，对本实施例提供的显示面板做具体说明，但本公开的实施例不限于此。
例如，图7A示出了本公开的实施例提供的一种显示面板的示意图。例如，如图7A和图7B所示，该显示面板包括子像素单元P、感测线SEN(例如，SEN1、SEN2、SEN3等)、扫描线(例如，G1-1、G1-2、G2-1、G2-2、G3-1、G3-2等)、数据线(例如，D1、D2、D3等)、栅极驱动电路110、控制电路120、数据驱动电路130和检测电路140。例如，扫描线G1-1、G2-1和G3-1分别连接至位于第一行、第二行和第三行的子像素单元P的像素电路第一晶体管的控制端G1，扫描线G1-2、G2-2和G3-2分别连接至位于第一行、第二行和第三行的子像素单元的像素电路第二晶体管的控制端G2。
例如，如图7A和图7B所示，显示面板的显示区域中的子像素单元包括该像素电路P，显示面板的位于显示区域之外的周边区域设置控制电路120，像素电路包括驱动晶体管，该驱动晶体管包括栅极和第一极，该感测线SEN与驱动晶体管的第一极连接。例如，控制电路120配置为执行本公开任一实施例提供的检测方法或本公开任一实施例提供的显示面板的驱动方法。例如，本实施例中的检测方法的具体实现方式可以参见图2示出的实施例，在此不再赘述。
例如，控制电路120还配置为控制栅极驱动电路110、数据驱动电路130和检测电路140。例如，数据驱动电路130配置为根据实际应用需求在不同的时刻提供参考数据电压和检测数据电压。栅极驱动电路110用于提供第一晶体管以及第二晶体管的扫描信号，从而控制第一晶体管以及第二晶体管的导通与截止。
例如，像素电路还配置为接收参考数据电压和检测数据电压并将参考数 据电压和检测数据电压在不同的时间施加至驱动晶体管的栅极。例如，检测电路140配置为从感测线SEN读取基准电压和初始感测电压。
例如，像素电路还包括第二开关晶体管T2，发光元件EL例如可以为有机发光二极管，但本公开的实施例不限于此。例如，驱动晶体管的第二极和第一极可以配置为分别连接至第一电源电压端VDD以及发光元件EL的第一极，发光元件EL的第二极连接到第二电源电压端VSS。例如，第二开关晶体管T2的第一极与驱动晶体管的第一极电连接，且第二开关晶体管T2的第二极与检测电路140电连接。例如，像素电路还包括感测线SEN，感测线SEN将上述第二开关晶体管T2的第二极与检测电路140电连接。
例如，像素电路还包括第一晶体管T1与存储电容Cst，第一晶体管T1配置为从数据驱动电路130获取数据信号，向驱动晶体管的栅极写入数据信号，存储电容Cst存储数据信号。例如，像素电路还可以包括信号线Vdat，第一晶体管T1的第一极连接到信号线Vdat。
例如，在一个示例中，控制器电路120为时序控制器(T-CON)。在另一个示例中，控制电路120还可以包括处理器(图中未示出)和存储器(图中未示出)，存储器包括可执行代码以及运行代码所需的数据或产生的数据，处理器运行可执行代码以执行本公开任一实施例提供的检测方法或本公开任一实施例提供的显示面板的驱动方法。
例如，该处理器例如是中央处理单元(CPU)或者具有数据处理能力和/或指令执行能力的其它形式的处理单元，例如，该处理器可以实现为通用处理器，并且也为单片机、微处理器、数字信号处理器、专用的图像处理芯片、或现场可编程逻辑阵列等。存储器例如可以包括易失性存储器和/或非易失性存储器，例如可以包括只读存储器(ROM)、硬盘、闪存等。相应地，该存储器可以实现为一个或多个计算机程序产品，所述计算机程序产品可以包括各种形式的计算机可读存储介质，在所述计算机可读存储介质上可以存储一个或多个可执行代码(例如，计算机程序指令)。处理器可以运行所述程序指令，以执行本公开任一实施例提供的检测方法，由此可以获取显示面板所包括的像素电路的驱动晶体管的阈值电压，进而可以实现显示面板的阈值补偿功能。例如，该存储器还可以存储其他各种应用程序和各种数据，例如每个像素电路的初始阈值电压，以及应用程序使用和/或产生的各种数据等。
例如，本实施例提供的显示面板可以去除初始感测电压中的环境噪声分量，由此使得所获得的感测电压和驱动晶体管的阈值电压更接近真实值，进而可以提升该显示面板的补偿效果以及亮度均匀度。
有以下几点需要说明：
(1)本公开实施例附图中，只涉及到与本公开实施例涉及到的结构，其他结构可参考通常设计。
(2)在不冲突的情况下，本公开同一实施例及不同实施例中的特征可以相互组合。
虽然上文中已经用一般性说明及具体实施方式，对本公开作了详尽的描述，但在本公开实施例基础上，可以对之作一些修改或改进，这对本领域技术人员而言是显而易见的。因此，在不偏离本公开精神的基础上所做的这些修改或改进，均属于本公开要求保护的范围。
以上所述仅是本公开的示范性实施方式，而非用于限制本公开的保护范围，本公开的保护范围由所附的权利要求确定。

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  1. 一种像素电路的检测方法，所述像素电路包括驱动晶体管，所述驱动晶体管包括栅极和第一极，所述驱动晶体管的第一极与感测线耦接，所述检测方法包括：
    在参考充电周期，向所述驱动晶体管的栅极施加参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的第一时长，从所述感测线获得基准电压；
    在数据充电周期，向所述驱动晶体管的栅极施加不同于所述参考数据电压的检测数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述检测数据电压后的所述第一时长，从所述感测线获得初始感测电压；
    其中，至少基于所述基准电压和所述初始感测电压获得所述像素电路的感测电压，并基于所述感测电压获得所述驱动晶体管的阈值电压。
  2. 根据权利要求1所述的检测方法，其中，所述参考数据电压为零。
  3. 根据权利要求1或2所述的检测方法，其中，所述像素电路的感测电压等于所述初始感测电压与所述基准电压的差值。
  4. 根据权利要求1-3任一所述的检测方法，其中，
    在相邻显示帧之间设置预定间隙；以及
    所述参考充电周期和所述数据充电周期均在同一个预定间隙中。
  5. 根据权利要求4所述的检测方法，其中，所述参考充电周期位于所述数据充电周期之前。
  6. 根据权利要求5所述的检测方法，还包括：
    在补充参考充电周期，向所述驱动晶体管的栅极施加所述参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的所述第一时长，从所述感测线获得补充基准电压；
    其中，
    所述参考充电周期、所述补充参考充电周期和所述数据充电周期均在同一个预定间隙中，且所述补充参考充电周期位于所述数据充电周期之后；以及
    基于所述基准电压、所述补充基准电压和所述初始感测电压获得所述像 素电路的感测电压。
  7. 根据权利要求6所述的检测方法，其中，
    所述像素电路的感测电压等于所述初始感测电压与所述基准电压和所述补充基准电压的平均值的差值。
  8. 根据权利要求1-7任一所述的检测方法，其中，
    所述像素电路还包括第一晶体管和存储电容，所述第一晶体管的第一极和第二极分别与信号线和所述驱动晶体管的栅极连接，所述存储电容的第一端和第二端分别与所述驱动晶体管的栅极和所述驱动晶体管的第一极连接；
    所述检测方法还包括：
    在所述参考充电周期中，打开所述第一晶体管，以在获得所述初始感测电压之前的时间段，将所述参考数据电压持续施加到所述驱动晶体管的栅极；以及
    在所述数据充电周期中，打开所述第一晶体管，以在获得所述初始感测电压之前的时间段，将所述检测数据电压持续施加到所述驱动晶体管的栅极。
  9. 根据权利要求8所述的检测方法，其中，
    所述像素电路还包括第二晶体管，所述第二晶体管的第一极与所述驱动晶体管的第一极连接，所述第二晶体管的第二极连接至所述感测线；
    所述检测方法还包括：
    在获得所述初始感测电压之前关闭所述第一晶体管和所述第二晶体管。
  10. 根据权利要求1-7任一所述的检测方法，其中，
    所述像素电路还包括第一晶体管和存储电容，所述第一晶体管的第一极和第二极分别与信号线和所述驱动晶体管的栅极连接，所述存储电容的第一端和第二端分别与所述驱动晶体管的栅极和所述驱动晶体管的第一极连接；
    所述检测方法还包括：
    在所述数据充电周期中，向所述驱动晶体管的栅极施加所述检测数据电压之后关闭所述第一晶体管，并在获得所述初始感测电压之前重新打开所述第一晶体管；以及
    在所述第一晶体管关闭期间，所述信号线向所述驱动晶体管的栅极提供的电压由所述检测数据电压转变为电压值小于所述检测数据电压的第二检测数据电压。
  11. 根据权利要求10所述的检测方法，其中，所述第二检测数据电压为零。
  12. 根据权利要求1-11任一所述的检测方法，其中，所述驱动晶体管的第二极与第一电源电压端耦接以接收第一电源电压。
  13. 一种显示面板的驱动方法，所述显示面板包括像素电路和感测线，所述像素电路包括驱动晶体管，所述驱动晶体管包括栅极和第一极，所述感测线与所述驱动晶体管的第一极耦接，所述驱动方法包括：
    在参考充电周期，向所述驱动晶体管的栅极施加参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的第一时长，从所述感测线获得基准电压；
    在数据充电周期，向所述驱动晶体管的栅极施加不同于所述参考数据电压的检测数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述检测数据电压后的所述第一时长，从所述感测线获得初始感测电压；
    其中，至少基于所述基准电压和所述初始感测电压获得所述像素电路的感测电压，并基于所述感测电压获得所述驱动晶体管的阈值电压。
  14. 如权利要求13所述的显示面板的驱动方法，还包括：根据所获得的所述阈值电压建立包括所述像素电路的子像素单元的补偿量。
  15. 如权利要求14所述的显示面板的驱动方法，还包括：
    在所述显示面板的显示操作期间，采用所述补偿量对所述子像素单元进行补偿操作。
  16. 一种显示面板，包括像素电路、感测线和控制电路，其中，
    所述像素电路包括驱动晶体管，所述驱动晶体管包括栅极和第一极，所述感测线与所述驱动晶体管的第一极耦接；
    所述控制电路配置为执行如下用于所述像素电路的检测方法或所述显示面板的驱动方法：
    在参考充电周期，向所述驱动晶体管的栅极施加参考数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施加所述参考数据电压后的第一时长，从所述感测线获得基准电压；
    在数据充电周期，向所述驱动晶体管的栅极施加不同于所述参考数据电压的检测数据电压以通过所述驱动晶体管的第一极对所述感测线充电，在施 加所述检测数据电压后的所述第一时长，从所述感测线获得初始感测电压；
    其中，至少基于所述基准电压和所述初始感测电压获得所述像素电路的感测电压，并基于所述感测电压获得所述驱动晶体管的阈值电压。
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Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108597449B (zh) * 2018-04-26 2020-04-21 京东方科技集团股份有限公司 像素电路的检测方法、显示面板的驱动方法和显示面板
CN109377944B (zh) * 2018-10-30 2020-11-27 京东方科技集团股份有限公司 像素驱动电路、显示面板及其驱动方法和显示装置
CN109658856B (zh) * 2019-02-28 2021-03-19 京东方科技集团股份有限公司 像素数据补偿参数获取方法及装置、amoled显示面板
CN111785195A (zh) * 2019-04-04 2020-10-16 合肥鑫晟光电科技有限公司 像素电路的驱动方法、补偿装置及显示设备
CN109961728B (zh) * 2019-04-10 2021-01-22 京东方科技集团股份有限公司 检测方法、驱动方法、显示装置和补偿查找表的构建方法
CN110288949B (zh) 2019-08-08 2021-01-26 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
CN110969989B (zh) * 2019-12-20 2021-03-30 京东方科技集团股份有限公司 像素电路的驱动方法和控制驱动方法
CN111044874B (zh) * 2019-12-31 2022-05-24 武汉天马微电子有限公司 一种显示模组、检测方法及电子设备
CN111048040B (zh) * 2020-01-02 2021-08-03 深圳市华星光电半导体显示技术有限公司 像素驱动电路电压补偿方法、电压补偿电路和显示面板
CN111179838A (zh) * 2020-02-21 2020-05-19 深圳市华星光电半导体显示技术有限公司 像素电路、显示面板及改善显示面板低灰阶均匀性的方法
CN114446207B (zh) * 2020-10-16 2023-12-08 合肥京东方卓印科技有限公司 像素电路检测方法、显示面板及其驱动方法、显示装置
CN114787906B (zh) * 2020-10-28 2024-06-14 京东方科技集团股份有限公司 显示装置、电压采集电路和方法
CN112863440A (zh) 2021-01-26 2021-05-28 京东方科技集团股份有限公司 像素补偿电路及其驱动方法、显示装置
KR20220120806A (ko) * 2021-02-23 2022-08-31 삼성디스플레이 주식회사 픽셀 회로, 이를 포함하는 표시 장치 및 이의 구동 방법
KR20230020148A (ko) * 2021-08-03 2023-02-10 엘지디스플레이 주식회사 표시 장치 및 구동 회로
CN114694615B (zh) * 2022-04-26 2023-04-07 合肥鑫晟光电科技有限公司 显示面板的驱动方法、驱动电路及显示面板

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20150071546A (ko) * 2013-12-18 2015-06-26 엘지디스플레이 주식회사 유기 발광 표시 장치
CN105427796A (zh) * 2014-09-12 2016-03-23 乐金显示有限公司 用于感测驱动元件的电特性的有机发光二极管显示器
CN105448238A (zh) * 2014-09-19 2016-03-30 乐金显示有限公司 有机发光显示装置
CN106328062A (zh) * 2015-06-30 2017-01-11 乐金显示有限公司 感测驱动tft的阈值电压的装置和方法
CN106782320A (zh) * 2016-12-29 2017-05-31 深圳市华星光电技术有限公司 Oled驱动薄膜晶体管的阈值电压侦测方法
KR20170081049A (ko) * 2015-12-31 2017-07-11 엘지디스플레이 주식회사 유기발광 표시 장치 및 그 oled 보상 방법
CN107665671A (zh) * 2016-07-29 2018-02-06 乐金显示有限公司 有机发光显示器及其感测方法
CN107749280A (zh) * 2017-12-06 2018-03-02 京东方科技集团股份有限公司 显示装置的驱动方法及显示装置
CN108597449A (zh) * 2018-04-26 2018-09-28 京东方科技集团股份有限公司 像素电路的检测方法、显示面板的驱动方法和显示面板

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5178631B2 (ja) * 2009-05-26 2013-04-10 株式会社ジャパンディスプレイウェスト タッチセンサ、表示装置および電子機器
KR102005052B1 (ko) 2012-12-03 2019-07-31 삼성디스플레이 주식회사 오차 보상부 및 이를 이용한 유기전계발광 표시장치
KR102109191B1 (ko) * 2013-11-14 2020-05-12 삼성디스플레이 주식회사 유기전계발광 표시장치 및 그의 구동방법
KR102083458B1 (ko) * 2013-12-26 2020-03-02 엘지디스플레이 주식회사 유기발광 표시장치
CN104700761B (zh) 2015-04-03 2017-08-29 京东方科技集团股份有限公司 一种检测电路及其检测方法和驱动系统
KR102603596B1 (ko) * 2016-08-31 2023-11-21 엘지디스플레이 주식회사 유기발광 표시장치와 그의 열화 센싱 방법
CN107657923B (zh) 2017-11-15 2020-02-21 合肥鑫晟光电科技有限公司 像素电路的检测方法、显示面板的驱动方法、显示装置及像素电路

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20150071546A (ko) * 2013-12-18 2015-06-26 엘지디스플레이 주식회사 유기 발광 표시 장치
CN105427796A (zh) * 2014-09-12 2016-03-23 乐金显示有限公司 用于感测驱动元件的电特性的有机发光二极管显示器
CN105448238A (zh) * 2014-09-19 2016-03-30 乐金显示有限公司 有机发光显示装置
CN106328062A (zh) * 2015-06-30 2017-01-11 乐金显示有限公司 感测驱动tft的阈值电压的装置和方法
KR20170081049A (ko) * 2015-12-31 2017-07-11 엘지디스플레이 주식회사 유기발광 표시 장치 및 그 oled 보상 방법
CN107665671A (zh) * 2016-07-29 2018-02-06 乐金显示有限公司 有机发光显示器及其感测方法
CN106782320A (zh) * 2016-12-29 2017-05-31 深圳市华星光电技术有限公司 Oled驱动薄膜晶体管的阈值电压侦测方法
CN107749280A (zh) * 2017-12-06 2018-03-02 京东方科技集团股份有限公司 显示装置的驱动方法及显示装置
CN108597449A (zh) * 2018-04-26 2018-09-28 京东方科技集团股份有限公司 像素电路的检测方法、显示面板的驱动方法和显示面板

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