CN110473501B - Compensation method of display panel - Google Patents

Compensation method of display panel Download PDF

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CN110473501B
CN110473501B CN201910812497.XA CN201910812497A CN110473501B CN 110473501 B CN110473501 B CN 110473501B CN 201910812497 A CN201910812497 A CN 201910812497A CN 110473501 B CN110473501 B CN 110473501B
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signal
phase
transistor
compensation
detection
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CN110473501A (en
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李玥
周星耀
张蒙蒙
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Wuhan Tianma Microelectronics Co Ltd
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Shanghai Tianma AM OLED Co Ltd
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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]
    • 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
    • G09G2320/046—Dealing with screen burn-in prevention or compensation of the effects thereof

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Electroluminescent Light Sources (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Control Of El Displays (AREA)

Abstract

The embodiment of the application provides a compensation method of a pixel compensation circuit of a display panel, wherein the pixel compensation circuit comprises a power supply signal end, a driving transistor, an organic light-emitting element and an electrode signal end which are connected in series; the power signal end is electrically connected with a power signal line; the compensation method comprises the steps of driving the pixel compensation circuit into an aging compensation stage; reading a first node potential at the aging compensation stage; the first node is provided between the driving transistor and the organic light emitting element; and, a first power supply signal is supplied to the power supply signal line in the aging compensation stage, the first power supply signal being of an alternating level. This application reduces the charge time in the ageing compensation stage through first power signal jump, shortens and listens the cycle, improves the efficiency of ageing compensation.

Description

Compensation method of display panel
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of display, in particular to a compensation method of a display panel.
[ background of the invention ]
With the upgrading of consumers, the vehicle-mounted display products gradually convert to Organic Light Emitting (OLED) display panels, but become application difficulties due to aging of OLED devices and threshold voltage (Vth) drift. The automobile is not as fast as a mobile phone, so that the display effect is greatly deteriorated after long-time and high-temperature use, and at the moment, the aging compensation needs to be carried out on the OLED display panel. And because the load on the detection line is large, the charging time is very long, the detection period is long, and the aging compensation efficiency is greatly reduced.
[ summary of the invention ]
In view of the above, embodiments of the present invention provide a compensation method for a display panel to solve the above technical problems.
The application provides a display panel compensation method, which comprises the following steps: the pixel compensation circuit comprises a power supply signal end, a driving transistor, an organic light-emitting element and an electrode signal end which are connected in series; the power signal end is electrically connected with a power signal line; the compensation method comprises the steps of driving the pixel compensation circuit into an aging compensation stage; reading a first node potential at the aging compensation stage; the first node is provided between the driving transistor and the organic light emitting element; and, a first power supply signal is supplied to the power supply signal line in the aging compensation stage, the first power supply signal being of an alternating level. This application reduces the charge time in the ageing compensation stage through first power signal jump, shortens and listens the cycle, improves the efficiency of ageing compensation.
[ description of the drawings ]
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of a display panel according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a pixel compensation circuit according to an embodiment of the present application;
FIG. 3 is a timing diagram illustrating aging compensation in the embodiment of FIG. 2;
FIG. 4 is a schematic diagram of node potentials according to an embodiment of the present application;
FIG. 5 is a schematic diagram of node potentials according to another embodiment of the present application;
FIG. 6 is a schematic diagram of a pixel compensation circuit according to another embodiment of the present application;
FIG. 7 is a timing diagram illustrating aging compensation according to the embodiment of FIG. 6;
FIG. 8 is a timing diagram illustrating the threshold compensation process of the embodiment shown in FIG. 6;
[ detailed description ] embodiments
For better understanding of the technical solutions of the present invention, the following detailed descriptions of the embodiments of the present invention are provided with reference to the accompanying drawings.
It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
It should be understood that although the terms first, second, third, etc. may be used to describe the supply voltages in the embodiments of the present invention, the supply voltages should not be limited to these terms. These terms are only used to distinguish supply voltages from each other. For example, the first power supply voltage may also be referred to as the second power supply voltage, and similarly, the second power supply voltage may also be referred to as the first power supply voltage, without departing from the scope of embodiments of the present invention.
As described in the background, aging compensation of OLED devices of display panels is required in OLED products such as automobiles that require long-term use. The OLED device is first charged to reach an equilibrium state (the OLED device acts as a capacitor, and the capacitor is fully charged to reach the equilibrium state). The aging compensation process requires connecting the sensing line to the OLED device through the driving chip IC to charge it. The trace lines inside the display panel overlap with other devices of the display panel, such as scan lines, data lines, reference signal lines, and other signal lines in the pixel circuit, thereby generating parasitic capacitance. The current generated by the IC flows through all the capacitors on the trace, and the OLED device can be charged after the trace is fully charged, so that the charging time is too long, which usually takes 6 ms. Taking the display panel with 720 × 1920 as an example, the time taken to scan 720 lines is 6ms × 720, which corresponds to a frequency of 1000ms/(6ms × 720) ≈ 0.23Hz, which is much lower than the frequency acceptable to consumers, greatly reducing the detection efficiency, and is not favorable for the whole detection process.
The present application provides a compensation method for a pixel compensation circuit, which is used to solve the above technical problems. Referring to fig. 1 and 2, fig. 1 is a schematic view of a display panel according to an embodiment of the present application; FIG. 2 is a schematic diagram of a pixel compensation circuit according to an embodiment of the present application;
referring to fig. 1, the display panel of the present application includes a display area AA, a non-display area NA surrounding the display area, and a pixel compensation circuit disposed in the display area AA. Referring to fig. 2, the pixel compensation circuit includes a power signal terminal PVDD, a driving transistor DT, an organic light emitting device OLED, and an electrode signal terminal PVEE connected in series; the power signal end PVDD is electrically connected with a power signal line Vdd;
the compensation method comprises driving the pixel compensation circuit 10 into an aging compensation stage; in the aging compensation stage, the driving chip IC reads the potential of the first node N1 through a Sense line Sense; the first node N1 is disposed between the driving transistor DT and the organic light emitting element OLED; and, the first power supply signal Vdd, which is an alternating level, is supplied to the power supply signal line Vdd in the aging compensation stage.
According to the aging detection method and device, the first power supply signal VDD is set to be the alternating level in the aging compensation stage, so that the first power supply signal VDD jumps, parasitic capacitance between the first power supply signal line Vdd and other elements of the display panel is charged through the coupling effect, the time for charging the parasitic capacitance by the detection line Sense of the IC in the detection stage is shortened, and the aging detection efficiency is improved. The inventor obtains through analog simulation that under the same other conditions, the first power supply signal VDD with fixed voltage is 4.6v, and the aging detection time is 6 ms; when the first power signal VDD changed to the alternating level jumps from 4.6v to 4.95v, the aging detection time is reduced to 4.5-4.9 ms, which is reduced by nearly 25%.
Specifically, please refer to fig. 2 to 4, fig. 3 is a schematic diagram of the aging compensation timing sequence of the embodiment of fig. 2; FIG. 4 is a schematic diagram of node potentials according to an embodiment of the present application;
taking the pixel compensation circuit described in fig. 2 as an example, the pixel compensation circuit includes a driving transistor DT and a power signal terminal PVDD disposed at a first pole of the driving transistor DT; an organic light emitting element OLED electrically connected to the second electrode of the driving transistor DT; a data writing transistor T1 connected to the gate of the driving transistor DT; a storage capacitor CST connected between the gate of the driving transistor DT and the power signal terminal PVDD; and a detection transistor T8 connected between the detection line Sense and the organic light emitting element OLED. The connection point of the detection transistor T8 and the organic light emitting element OLED is a first node N1.
In the light emission timing of the pixel compensation circuit, in the light emission preparation stage, the data writing transistor T1 is first turned on, and a data signal is written into the gate of the driving transistor DT; in the light emitting period, the data writing transistor is turned off, and the data signal is stored in the gate of the driving transistor, i.e., the second node N2, through the storage capacitor CST. It should be noted that fig. 2 is only an example of a pixel compensation circuit, and the pixel compensation circuit and the operation stage thereof are not limited thereto.
With continued reference to fig. 3, during the aging compensation phase, the aging compensation phase includes a reset phase P1, a charge balance phase P2 and a detect phase P3;
in the compensation phase of a pixel row, a reset current is supplied to the first node N1 in the reset phase P1; therefore, each detection is started from the same starting point, the variables can be controlled as much as possible, and the detection result is more accurate. The compensation for the inaccurate aging detection result cannot compensate the display abnormality caused by the aging of the organic light emitting device, but deteriorates the display result. In order to make the result of the burn-in detection more accurate, the first node N1 electrically connected to the organic light emitting device needs to be reset before each detection starts or after the detection ends;
providing a reference current I to a first node N1 during a charge balance phase P2baseSo that the organic light emitting element OLED is balanced; the principle of detecting the aging of the organic light emitting device OLED is to provide current for the organic light emitting device OLED and test the organic light emitting deviceThe aging degree of the organic light emitting element OLED is judged according to the drift of the I-V characteristic of the device. The principle of the present application is to provide a precise reference current I for the organic light emitting device OELDbaseThe voltage is detected to obtain the I-V characteristic. The inventors have made extensive studies and found that the organic light emitting element OLED fabricated in the organic light emitting display panel has a stacked structure. A hole functional layer, a luminescent layer functional layer and an electron functional layer are arranged between the anode and the cathode. The cathode, the anode and the functional layer therebetween correspond to a plate of a capacitor and a dielectric layer therebetween, and therefore, the organic light emitting element OLED corresponds to a capacitor. Before detection, the capacitor of the organic light-emitting element OLED needs to be fully charged, so that the inventor adds a charge balance stage to a compensation stage to obtain accurate I-V characteristics.
Reading the potential of the first node N1 at the detection stage P3; the electrode signal end of the organic light-emitting element OLED is set as an electrode signal VEE, the I-V characteristic of the organic light-emitting element OLED is obtained according to the detected potential of the first node N1, the electrode signal VEE at the other end of the organic light-emitting element OLED and the provided reference current, and the aging condition of the organic light-emitting element OLED is obtained after the detected I-V characteristic is compared with the initial I-V characteristic stored in the IC and is used for subsequent compensation.
The level of the first power signal VDD transitions at the beginning of the charge balance phase P2 or before the charge balance phase P2. The reference current I due to the presence of parasitic capacitance on the Sense line SensebaseThe charging speed of (2) is very slow, resulting in low aging detection efficiency. The first power signal VDD jumps by jumping at the beginning of the charge balance stage P2 or jumping before the charge balance stage P2, so that the first power signal VDD jumps, parasitic capacitance between the first power signal Vdd and other elements of the display panel is charged through coupling, the time for charging the parasitic capacitance by the sensing line sense of the IC in the sensing stage is shortened, and the aging sensing efficiency is improved.
Specifically, the level of the first power supply signal VDD jumps from the first power supply voltage VDD1 to the second power supply voltage VDD 2; the second power supply voltage VDD2 is greater than the first power supply voltage VDD 1; the difference between the second power voltage VDD2 and the electrode signal VEE is smaller than the threshold voltage of the organic light emitting element OLED. Wherein the threshold voltage of the OLED is a minimum voltage that can turn on the organic light emitting element OLED. In the present application, the charging time of the organic light emitting element OLED by the reference current is reduced by the difference between the second power voltage VDD2 and the first power voltage VDD 1. On one hand, the larger the difference value is, the larger the coupled voltage is, the more the improved efficiency is; on the other hand, too high the first power supply signal VDD may cause the organic light emitting element OLED to be sneak. In this embodiment, the difference between the second power voltage VDD2 and the electrode signal VEE is set to be smaller than the threshold voltage of the organic light emitting device OLED, so as to ensure that the difference between the first power signal VDD and the electrode signal VEE does not cause the organic light emitting device OLED to be turned on during the reset phase P1, the charge balance phase P2 and the detection phase P3.
Since the charging time of the reference current can be reduced only if the first power signal VDD jumps from a lower level to a higher level. However, when the first power signal VDD jumps to a value that is equal to the threshold voltage of the organic light emitting device OLED, the first power signal VDD cannot jump further, otherwise the organic light emitting device OLED may be turned on. It is therefore desirable to set the first power supply signal VDD to transition between the first power supply voltage VDD1 and the second power supply voltage VDD 2. In order to prevent the first power signal from jumping from the second power voltage VDD2 to the first power voltage VDD1 and decreasing the potential of the first node N1, the level of the first power signal jumps back to the first power voltage VDD1 from the second power voltage VDD2 after the detection phase P3 completes the detection and before the next pixel row reset phase P1 begins. On one hand, the arrangement is that the first node potential is lowered after detection, and the detection is not influenced; on the other hand, the influence caused by the jump-down of the first power supply voltage can be quickly eliminated through the reset phase.
In order to further reduce the time of the charge balancing stage, the efficiency of the aging detection is improved. In the compensation phase of a pixel row, the charge balance phase P2 includes a first charge balance phase P21 and a second charge balance phase P22; providing a precharge current I during a first charge balance phase P21preA pre-charge current IpreGreater than the reference current Ibase. The present embodiment passes through a precharge current IpreThe parasitic capacitance is charged with a large current, and then the current balance passing through the organic light emitting element OLED is used as a reference current for aging detection. The aging detection accuracy is guaranteed, meanwhile, the aging detection time is greatly reduced, and the aging detection efficiency is improved.
In particular, a pre-charge stream IpreIs greater than or equal to three times the reference current IbaseAbsolute value of (a). Due to the reference current IbaseThe current for charging the sense line sense is small in the order of nanoamperes and the reference current IbaseIs provided by a driving chip IC, and has weak charging capability. Setting a smaller pre-charge current does not have the effect of shortening the charging time. The pre-charging current is set to be more than 3 times of the reference current, so that the aging detection accuracy is guaranteed, the aging detection time is greatly reduced, and the aging detection efficiency is improved.
Further, a pre-charge stream IpreThe excessive charging time may cause the overcharge, so that the parasitic capacitor of the sensing line sense reversely discharges the organic light emitting device OLED in the stage of charging the reference current and sensing the reference current, the sensed voltage of the first node N1 is not the voltage corresponding to the reference current, and the sensed aging condition of the organic light emitting device OLED is inaccurate, thereby causing the erroneous aging compensation. Therefore, in order to avoid the above problems and achieve the improved detection efficiency, the first charge balance phase P21 lasts for the first time t 1; a second charge balance phase P22 for a second time t 2; the first time t1 is less than or equal to one-half of the second time t2 to avoid overcharging.
Further, please refer to fig. 6 to 8, wherein fig. 6 is a schematic diagram of a pixel compensation circuit according to another embodiment of the present application; FIG. 7 is a timing diagram illustrating aging compensation according to the embodiment of FIG. 6; FIG. 8 is a timing diagram illustrating the threshold compensation process of the embodiment shown in FIG. 6;
the pixel compensation circuit includes: a sense signal terminal Vsense, and a sense transistor T8 disposed between the sense signal terminal Vsense and the first node N1. The Sense signal terminal Vsense is connected to the Sense line Sense.
The detection transistor T8 is controlled by the detection control signal VS; in the reset phase P1, the charge balance phase P2 and the detection phase P3, the driving transistor DT is turned off; in this embodiment, the driving transistor DT is in an off state in the aging compensation timing sequence, so as to avoid generating a driving current to affect the aging detection result.
In a reset phase P1, the sense control signal VS provides an active level, and the sense signal terminal Vsense provides a reset current to the first node N1; the organic light-emitting element OLED is reset through the reset current, so that the organic light-emitting element OLED starts from the same state every time of aging detection, and the detection result is more accurate.
During the charge balance phase P2, the sense control signal VS provides an active level, and the sense signal terminal Vsense provides a reference current to the first node N1; providing a stable reference current I for an organic light emitting element OLEDbase。
In the detecting phase P3, the detecting control signal VS provides an active level to detect the signal at the first node N1. And detecting the voltage of the organic light-emitting element OLED according to the reference current so as to obtain the I-V characteristic of the organic light-emitting element OLED, comparing the I-V characteristic with the initial I-V characteristic stored in the drive chip IC, judging the aging degree of the organic light-emitting element OLED, and further compensating the aging degree.
Specifically, the pixel compensation circuit includes: a first light emission control transistor T3 disposed between the power signal terminal PVDD and the driving transistor DT;
a DATA signal terminal DATA, and a DATA writing transistor T1 provided directly between the DATA signal terminal DATA and the driving transistor DT;
a second light emission control transistor T4 between the driving transistor DT and the organic light emitting element OLED;
an initialization signal terminal VREF, and a gate initialization transistor T6 disposed between the initialization signal terminal VREF and the gate of the driving transistor DT; an anode initialization transistor T2 disposed between the initialization signal terminal VREF and the first node N1;
and a compensation transistor T5 disposed between the first electrode and the gate electrode of the driving transistor DT.
In this embodiment, the detection transistor T8 is directly connected to the organic light emitting device OLED, and the reference current writing and the aging detection need not pass through any other transistor, so that the change of the Vgs-Ids characteristic of the other transistor with respect to the reference current and the detection voltage can be avoided.
Further, the detection transistor T8 is controlled by the detection control signal VS; the first and second light emission control transistors T3 and T4 are controlled by a light emission control signal EMIT; the gate initialization transistor T6 and the anode initialization transistor T2 are controlled by a first scan signal SA; the data writing transistor T1 and the compensating transistor T5 are controlled by the second scan signal SB;
in the aging compensation timing, the aging compensation timing is,
the first scan signal SA, the second scan signal SB, and the emission control signal EMIT provide off levels during the reset phase P1, the charge balance phase P2, and the detect phase P3; in the embodiment, in addition to the detection transistor T8, the driving transistor DT, the gate initialization transistor T6, the anode initialization transistor T2, the first light emission control transistor T3, the second light emission control transistor T4, the data writing transistor T1, and the compensation transistor T5 are turned off in the aging compensation timing, so as to avoid the driving current from affecting the aging detection result. Variations in the Vgs-Ids characteristics of the other transistors with respect to the reference current and the detected voltage are also avoided.
In the reset phase P1, the sense control signal VS provides an active level, and the sense signal terminal Vsense provides a reset current to the first node N1; the organic light-emitting element OLED is reset through the reset current, so that the organic light-emitting element OLED starts from the same state every time of aging detection, and the detection result is more accurate.
During the charge balance phase P2, the sense control signal VS provides an active level, and the sense signal terminal Vsense provides a reference current to the first node N1; a stable reference current is supplied to the organic light emitting element OLED.
In the detection phase P3, the detection control signal VS provides an active level to detect the first node signal. And detecting the voltage of the organic light-emitting element OLED according to the reference current so as to obtain the I-V characteristic of the organic light-emitting element OLED, comparing the I-V characteristic with the initial I-V characteristic stored in the drive chip IC, judging the aging degree of the organic light-emitting element OLED, and further compensating the aging degree.
Further, the compensation method further comprises a threshold compensation stage:
the threshold compensation phase comprises an initialization phase P4, a threshold capture phase P5 and a light-emitting phase P6;
in the initialization phase P4, the threshold capture phase P5, and the light emission phase P6, the detection control signal VS provides a turn-off level to turn off the detection transistor T8;
in the initialization phase P4, the first scan signal SA provides an on level, the second scan signal SB and the light emission control signal EMIT provide an off level, and the gate initialization transistor t6 is turned on to initialize the driving transistor DT; it should be noted that the active level here refers to a level at which a transistor which can be controlled by the active level is in a conducting state, for example, in the PMOS type photo-sensing driving circuit of fig. 6, the active level refers to a low level. The initialization signal Vref is transmitted to the driving transistor DT to reset the driving transistor DT.
In the threshold grabbing phase P5, the second scan signal SB provides an on level, the first scan signal SA and the emission control signal EMIT provide an off level; the data writing transistor T1 and the compensation transistor T5 are turned on, so that the data signal is written into the gate of the driving transistor DT and self-compensation is completed; at the same time, the anode initialization transistor T2 is turned on, and the initialization signal is transmitted to the organic light emitting element OLED to reset the organic light emitting element OLED. The data signal is transmitted to the gate of the driving transistor DT through the first pole of the data writing transistor T1, the driving transistor DT and the compensating transistor T5, and the voltage Vref stored at the gate of the driving transistor at the previous time is raised until the driving transistor 40 is turned off when the voltage level at the gate of the driving transistor is VDATA-Vth, where Vth is the threshold voltage of the driving transistor. Due to the process of manufacturing transistors, even if the same process parameters are satisfied during the manufacturing of the transistors, the threshold voltages of the transistors on the display panel are different, and the threshold voltages of the transistors drift with the increase of the service time after the transistors age, which causes the brightness of the same written data signals at different positions of the display panel to be different, and the brightness of the same written data signals displayed with the increase of the service time also to be different, which causes the display to be uneven and the color to drift. Therefore, the present embodiment grasps and stores the threshold voltage of the driving transistor DT to the gate of the driving transistor in order to eliminate the influence of the threshold voltage on the light emission luminance.
In the light emitting period P6, the light emission control signal EMIT provides an on level, and the first and second scan signals SA and SB provide an off level; the driving transistor DT generates a driving current and causes the organic light emitting element OLED to emit light. The first light emitting control transistor T3 is turned on, and the first power signal VDD is transmitted to the first pole of the driving transistor DT to make the driving transistor DT generate the driving current; the second light emission controlling transistor T4 is turned on to transmit the driving current to the organic light emitting element OLED. The driving current Ids generated by the driving transistor DT is 1/2Cox mu W/L (Vsg-Vth) ^2 ^ 1/2Cox mu W/L (VDD- (VDATA-Vth) -Vth) ^2 ^ 1/2Cox mu W/L (VDD-VDATA) ^ 2. It can be seen that the light emission current of the present embodiment depends on the written data signal regardless of the threshold voltage of the driving transistor DT through the compensation of the data writing period P5, and thus, the influence of the non-uniformity and the drift of the threshold voltage of the driving transistor DT on the light emission current is eliminated.
Referring to fig. 1, the present application further discloses a display panel and a display device. The display panel display device of the present application may include the compensation method as described above. Including but not limited to cellular phones, tablets, displays for computers, displays for smart wearable devices, display devices for vehicles such as automobiles, and the like. The display device is considered to fall within the scope of protection of the present application as long as the display device includes the compensation method included in the display device disclosed in the present application.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (10)

1. A compensation method of a pixel compensation circuit is characterized in that the pixel compensation circuit comprises a power supply signal end, a driving transistor, an organic light-emitting element and an electrode signal end which are connected in series; the power signal end is electrically connected with a power signal line;
the compensation method comprises the steps of driving the pixel compensation circuit into an aging compensation stage; reading a first node potential at the aging compensation stage; the first node is provided between the driving transistor and the organic light emitting element; and, providing a first power supply signal to the power supply signal line during the aging compensation phase, the first power supply signal being of alternating level;
the aging compensation stage comprises a reset stage, a charge balance stage and a detection stage;
providing a reset current to the first node during the reset phase in a compensation phase for a row of pixels; providing a reference current to the first node to balance the organic light emitting element during the charge balancing phase; reading the first node potential in the detection stage;
the level of the first power supply signal jumps at the beginning of the charge balancing phase or before the charge balancing phase;
the level of the first power supply signal jumps from a first power supply voltage to a second power supply voltage; the second supply voltage is greater than the first supply voltage; the difference between the second power supply voltage and the electrode signal is smaller than the threshold voltage of the organic light emitting element.
2. Compensation method according to claim 1,
after the detection phase is completed and before the next pixel column reset phase begins, the level of the first power supply signal jumps back to the first power supply voltage from the second power supply voltage.
3. Compensation method according to claim 1,
in a compensation phase of a pixel row, the charge balancing phase comprises a first charge balancing phase and a second charge balancing phase;
providing a pre-charge current during the first charge balance phase, the pre-charge current being greater than the reference current.
4. The compensation method of claim 3,
the absolute value of the precharge current is equal to or greater than three times the absolute value of the reference current.
5. The compensation method of claim 4,
the first charge balance phase lasts for a first time; the second charge balance phase lasts for a second time; the first time is less than or equal to one-half of the second time.
6. The compensation method of claim 1, wherein the pixel compensation circuit comprises: a detection signal terminal, and a detection transistor disposed between the detection signal terminal and the first node; the detection signal end is connected with a detection line.
7. The compensation method of claim 6, wherein the pixel compensation circuit comprises:
the detection transistor is controlled by a detection control signal; the driving transistor is turned off in the reset phase, the charge balancing phase and the detecting phase;
in the reset phase, the detection control signal provides an active level, and the detection signal terminal provides a reset current to the first node;
in the charge balancing stage, the detection control signal provides an active level, and the detection signal terminal provides a reference current to the first node;
in the probing phase, the detection control signal provides an active level to probe the first node signal.
8. The compensation method of claim 6, wherein the pixel compensation circuit comprises:
the first light-emitting control transistor is arranged between the power supply signal end and the driving transistor;
a data signal terminal, and a data write transistor disposed directly between the data signal terminal and the driving transistor;
a second light emission control transistor between the driving transistor and the organic light emitting element;
the initialization signal end and the grid initialization transistor are arranged between the initialization signal end and the grid of the driving transistor; an anode initialization transistor disposed between the initialization signal terminal and the first node; and a compensation transistor disposed between the first pole and the gate of the driving transistor.
9. The compensation method of claim 8, wherein the detection transistor is controlled by a detection control signal; the first light-emitting control transistor and the second light-emitting control transistor are controlled by a light-emitting control signal; the gate initialization transistor and the anode initialization transistor are controlled by a first scanning signal; the data writing transistor and the compensation transistor are controlled by a second scanning signal;
the first scan signal, the second scan signal, and the light emission control signal provide off levels in the reset phase, the charge balance phase, and the sensing phase;
in the reset phase, the detection control signal provides an active level, and the detection signal terminal provides a reset current to the first node;
in the charge balancing stage, the detection control signal provides an active level, and the detection signal terminal provides a reference current to the first node;
in the probing phase, the detection control signal provides an active level to probe the first node signal.
10. The compensation method according to claim 9, characterized in that it further comprises a threshold compensation phase:
the threshold compensation stage comprises an initialization stage, a threshold capture stage and a light-emitting stage;
in the initialization phase, the threshold capture phase and the light emitting phase, the detection control signal provides a cut-off level to cut off the detection transistor;
in the initialization stage, the first scan signal provides an on level, the second scan signal and the light emission control signal provide an off level; the gate initialization transistor is turned on to initialize the driving transistor;
in the threshold capture phase, the second scan signal provides an on level, the first scan signal and the light emission control signal provide an off level; the data writing transistor is conducted with the compensation transistor, so that a data signal is written into the grid electrode of the driving transistor and self-compensation is completed;
the light emission control signal provides an on level, the first scan signal and the second scan signal provide an off level in the light emission period; the driving transistor generates a driving current and causes the organic light emitting element to emit light.
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