KR20140004917A - Organic light emitting diode display device and method for driving the same - Google Patents

Abstract

According to an embodiment of the present invention, an organic light emitting diode display device includes a display panel having data lines, scan lines and matrix type pixels of m×n (m and n are natural numbers); an external compensation circuit compensating for digital image date corresponding to different scales by calculating the drain-source current of a driving TFT in other different scales by using the drain-source current of each driving TFT of the pixels measured by a peak white scale; a data driving circuit supplying data voltages to the data lines by changing a compensated digital image data into analog data voltages; and a scan driving circuit supplying scan signals to scan lines.

Description

Technical Field [0001] The present invention relates to an organic light emitting diode (OLED) display device,

The present invention relates to an organic light emitting diode display device capable of compensating the threshold voltage of a driving thin film transistor (TFT) of each pixel and a driving method thereof.

As the information society develops, the demand for display devices for displaying images is increasing in various forms. In recent years, various flat panel display devices such as a liquid crystal display (LCD), a plasma display panel (PDP), and an organic light emitting diode (OLED) have been used . Among these flat panel display devices, organic light emitting diode display devices are capable of low voltage driving, are thin, have excellent viewing angles, and have a high response speed. An active matrix type organic light emitting diode display device in which a plurality of pixels are arranged in a matrix form to display an image is widely used in organic light emitting diode display devices.

The display panel of the active matrix type organic light emitting diode display includes a plurality of pixels arranged in a matrix form. Each pixel measures a scan thin film transistor (TFT) that supplies the data voltage of the data line in response to the scan signal of the scan line, and an amount of current supplied to the organic light emitting diode (OLED) according to the supplied data voltage. And a driving TFT to adjust. In this case, the drain-source current Ids of the driving TFT supplied to the organic light emitting diode may be expressed by Equation 1 below.

In Equation 1, k 'is a proportional coefficient determined by the structure and physical characteristics of the driving TFT, Vgs is a gate-source voltage of the driving TFT, and Vth is a threshold voltage of the driving TFT.

On the other hand, due to the shift of the threshold voltage Vth due to the deterioration of the driving TFT, the threshold voltage Vth of the driving TFT of each of the pixels may have different values. In this case, since the drain-source current Ids of the driving TFT depends on the threshold voltage Vth of the driving TFT, even if the same data voltage is supplied to each of the pixels, the current Ids supplied to the organic light emitting diode is for each pixel. Different. Therefore, even if the same data voltage is supplied to each of the pixels, a problem arises in that the luminance of light emitted from the organic light emitting diode of each of the pixels is changed. In order to solve this problem, various methods for compensating the threshold voltage Vth of the driving TFT have been proposed.

The present invention provides an organic light emitting diode display device capable of compensating the threshold voltage of a driving TFT of each pixel and a driving method thereof.

An organic light emitting diode display according to an exemplary embodiment of the present invention includes a display panel including m x n pixels (m, n is a natural number) formed in data lines, scan lines, and a matrix; Digital image data corresponding to the other gray levels by calculating the drain-source current of the driving TFT from the other gray levels using the drain-source current of the driving TFT of each of the pixels measured at the peak white gray level. External compensation circuit to compensate for; A data driving circuit converting the compensated digital image data into analog data voltages and supplying the data voltages to the data lines; And a scan driving circuit configured to supply scan signals to the scan lines.

A method of driving an organic light emitting diode display according to an exemplary embodiment of the present invention includes an organic light emitting diode including a display panel including m x n (m, n is a natural number) pixels formed in data lines, scan lines, and a matrix. A method of driving a light emitting diode display device, the method comprising: (A) using a drain-source current of a driving TFT of each of the pixels measured at a peak white gray level to obtain a drain-source current of the driving TFT at other gray levels; Compensating the digital image data corresponding to the other gray levels by calculating; (B) converting the compensated digital image data into analog data voltages, and supplying the data voltages to the data lines; And (C) supplying scan signals to the scan lines.

The present invention calculates the drain-source current of the driving TFT in other grayscales by using the drain-source current of the driving TFT of each of the pixels measured at the peak white gray level, and the calculated drain-source of the driving TFT is calculated. The current may be used to compensate digital image data corresponding to other gray levels. As a result, the present invention can be accurately compensated even in low gradation, and can be implemented as a low-capacity memory, thereby reducing the cost.

1 is a block diagram schematically illustrating an organic light emitting diode display according to an exemplary embodiment of the present invention.
FIG. 2 is a block diagram illustrating in detail the external compensation circuit of FIG. 1. FIG.
3 is a flow chart showing an external compensation method according to an embodiment of the present invention.
4A is an exemplary diagram showing pixels of (1,1) to (m, n) coordinates.
4B is an exemplary diagram illustrating a first data map of digital image data.
4C is an exemplary diagram showing a second data map of peak white data, and a first mask;
5 is a table showing the PSNR according to the degree of deterioration and deterioration correlation.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The names of components used in the following description are selected in consideration of ease of specification, and may be different from actual product names.

The present invention relates to an organic light emitting diode display device that externally compensates for a threshold voltage of a driving TFT of each pixel. Internal compensation means sensing the threshold voltage of the driving TFT in real time in each of the pixels to compensate. External compensation means sensing the drain-source current of the driving TFT, compensating digital image data to be supplied to the pixels by using the sensed current, and then supplying compensation digital image data to the pixels.

1 is a block diagram schematically showing an organic light emitting diode display device according to an embodiment of the present invention. Referring to FIG. 1, an organic light emitting diode display according to an exemplary embodiment of the present invention may include a display panel 10, a scan driving circuit 110, a data driving circuit 120, a timing controller 130, and an external compensation circuit. 140, and an analog to digital converter 150, and the like.

The display panel 10 is formed such that the data lines D and the scan lines S cross each other. In the display panel 10, a pixel array in which pixels P are disposed in a matrix form is formed in an intersection area between the data lines D and the scan lines S. FIG. Each of the pixels P of the display panel 10 includes at least one thin film transistor, a driving TFT, an organic light emitting diode element, and at least one capacitor. Each of the pixels P controls an electric current flowing through the organic light emitting diode element using a switching TFT and a driving TFT to display an image. The display panel 10 may display an image in the form of bottom emission and top emission depending on the pixel structure.

In addition, current sensing lines I for sensing the drain-source current of the driving TFT of each of the pixels P may be formed in the display panel 10. To this end, each of the current sensing lines I is connected to each of the pixels P and is connected to an analog-to-digital converter 150. Alternatively, the present invention does not form separate current sensing lines I, but may use the drain-source of the driving TFT by using any one of the scan lines S, the data lines D, and other power lines. You can also sense current. In this case, the analog-to-digital converter 150 may be connected to any one of the scan lines S, the data lines D, and other power lines.

The data driving circuit 120 includes a plurality of source drive ICs. The source drive ICs receive the digital video data RGB 'compensated for the threshold voltage of the driving TFT from the timing controller 130. The source drive ICs convert compensation digital video data RGB 'into an analog data voltage in response to a source timing control signal DCS from the timing controller 130, and synchronize the analog data voltage with a scan pulse to display the same. The data lines D of the panel 10 are supplied. The data driving circuit 120 may be mounted on a tape carrier package (TCP), may be bonded to a lower substrate of the display panel 10 by a tape automated bonding (TAB) process, and may be a source printed circuit board (PCB). Can be connected to. The data driving circuit 120 may be bonded to the lower substrate of the display panel 10 by a chip on glass (COG) process.

The scan driving circuit 110 supplies at least one scan pulse to the scan lines for controlling at least one switching TFT. The scan driving circuit 110 may be mounted on the TCP and may be bonded to the lower substrate of the display panel 10 by a TAB process. In addition, the scan driving circuit 110 may be directly formed on the lower substrate simultaneously with the pixel array by a gate in panel (GIP) process.

The timing controller 130 receives compensation digital video data RGB ′ from the external compensation circuit 140. In addition, the timing controller 130 may include a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, a dot clock, and the like from the external compensation circuit 140. Receives a timing signal of. The timing controller 130 generates timing control signals for controlling the operation timing of the scan driving circuit 110 and the data driving circuit 120 based on the compensation digital video data RGB ′ and the timing signal. The timing control signals include a scan timing control signal GCS for controlling the operation timing of the scan driving circuit 110 and a data timing control signal DCS for controlling the operation timing of the data driving circuit 120. The timing controller 130 outputs the scan timing control signal GCS to the scan driving circuit 110 and outputs the data timing control signal DCS to the data driving circuit 120.

The external compensation circuit 140 receives digital image data (RGB) and timing signals from an external host system through an interface such as a low voltage differential signaling (LVDS) interface and a transition minimized differential signaling (TMDS) interface. The external compensation circuit 140 uses the drain-source current of the driving TFT of each of the pixels P measured at the peak white gray level, and the drain-source current of the driving TFT at other gray levels. The digital image data RGB corresponding to the other gray levels is compensated by estimating. Peak white gradation means the highest gradation among the gradations that can be expressed. For example, 8-bit digital image data may be represented by grayscales of G0 to G255, and the peak white grayscale of the 8-bit digital image data is G255 grayscale. A detailed description of the external compensation method of the external compensation circuit 140 will be described later with reference to FIGS. 2 to 4. Meanwhile, the external compensation circuit 140 may be designed to be embedded in the timing controller 130.

The organic light emitting diode display may further include a power supply unit (not shown). The power supply unit supplies voltages of various levels such as the high potential voltage VDD and the low potential voltage VSS to the display panel 10. In addition, the power supply unit supplies the gate high voltage VGH and the gate low voltage VGL to the scan driver 110.

FIG. 2 is a block diagram illustrating in detail the external compensation circuit of FIG. 1. 3 is a flowchart illustrating an external compensation method according to an exemplary embodiment of the present invention. 2 and 3, the external compensation circuit 140 includes a memory 141, a compensation reference data calculator 142, and a data compensator 143. Hereinafter, an external compensation method of the external compensation circuit 140 will be described in detail with reference to FIGS. 2 and 3.

First, m × n (m, n is a natural number) pixels may be formed in a pixel array of the display panel 10. Also, m × n pixels of the display panel 10 are pixels P (1,1) to (1,1) to (m, n) coordinates as shown in FIG. 4A by using the x coordinate and the y coordinate. P (m, n)). The timing controller 130 controls the scan driving circuit 110 and the data driving circuit 120 at predetermined periods so that the pixels P (1,1) to P of (1,1) to (m, n) coordinates are controlled. The data voltage corresponding to the peak white gray level is supplied to (m, n), and the pixels P (1,1) to P (m, n) having coordinates (1,1) to (m, n) The drain-source current of each driving TFT is sensed. The predetermined period can be appropriately set in consideration of the degree of deterioration of the driving TFT. For example, the predetermined period may be implemented as one frame period, G (G is a natural number of two or more) frame periods, seconds, minutes, hours, or the like. The analog-to-digital converter 150 drives each of the pixels P (1,1) to P (m, n) having coordinates (1,1) to (m, n) through current sensing lines I. The drain-source current of the TFT is input. The drain-source current of the driving TFT of each of the pixels P (1,1) to P (m, n) in (1,1) to (m, n) coordinates is transferred to the analog-to-digital converter 150. By the peak white data PWD of (1,1) coordinates to (m, n) coordinates. The analog-to-digital converter 150 outputs peak white data PWM of coordinates (1,1) to (m, n) to the memory 141. The memory 141 stores peak white data PWM of coordinates (1,1) to (m, n). (S101, S102)

The compensation reference data calculator 142 receives digital image data of one frame period from an external host system. The compensation reference data calculator 142 creates the first data map MAP1 by arranging digital image data of one frame period as shown in FIG. 4B. The digital image data of one frame period includes m × n digital image data. That is, the digital image data of one frame period may be represented by digital image data having (1,1) coordinates to (m, n) coordinates. The digital image data of the (1,1) coordinate is digital data to be written into the pixel of the (1,1) coordinate after being converted into an analog data voltage by the data driving circuit 120.

In addition, the compensation reference data calculator 142 receives peak white data PWD of (1,1) to (m, n) coordinates from the memory 141. The compensation reference data calculator 142 creates the second data map MAP2 by arranging peak white data PWM of coordinates (1,1) to (m, n) as shown in FIG. 4C.

The compensation reference data calculating unit 142 is a digital image data (RGB (p, q) of (p, q) (p is a natural number satisfying 1≤p≤m, q is a natural number satisfying 1≤q≤n) If)) corresponds to the peak white gradation, select the peak white data (PWD (p, q)) at (p, q) coordinates as the compensation reference data (CRD (p, q)) at (p, q) coordinates. do. The compensation reference data calculator 142 outputs the compensation reference data CRD (p, q) of the selected (p, q) coordinates to the data compensator 143. (S103, S104)

The peak white data PWD of (1,1) to (m, n) coordinates are pixels P (1,1) to (1,1) to (m, n) coordinates in the peak white gradation. P (m, n)) is a value obtained by converting the drain-source current of each driving TFT into digital data. The compensation reference data calculator 142 calculates the compensation reference data when the digital image data RGB (p, q) of the (p, q) coordinates does not correspond to the peak white gray level. A value obtained by converting the drain-source current of the driving TFT of the pixel of the pixel into digital data is required. However, when the digital image data RGB (p, q) of the (p, q) coordinate corresponds to a low grayscale such as black grayscale, the drain-source current of the driving TFT is too small, so that accurate sensing is difficult. In addition, it is difficult to convert the drain-source current of the driving TFT of each pixel for all gray levels into digital data, and even if it is converted, a large capacity memory is required to store many values, which inevitably increases the cost. The disadvantage is that. Therefore, when the digital image data RGB (p, q) of the (p, q) coordinates does not correspond to the peak white gray level, the compensation reference data calculating unit 142 performs (1,1) to (m, n) coordinates. Compensation reference data of the (p, q) coordinate is calculated by estimating the compensation reference data of the (p, q) coordinate using the peak white data PWD of the coordinate.

The compensation reference data calculator 142 calculates the compensation reference data of the (p, q) coordinate using the peak white data PWD of the (1,1) to (m, n) coordinate through the following process. It can be estimated. According to an exemplary embodiment of the present invention, the peak white data PWD having coordinates of (1,1) to (m, n) may be representative values that determine the degree of degradation of each pixel in the peak white gray level. The peak white data PWD of these (1,1) to (m, n) coordinates will follow a normal distribution. Further, the drain-source current of the driving TFT of each of the pixels P (1,1) to P (m, n) having coordinates of (1,1) to (m, n) in a gray level other than the peak white gray level. Can be said to follow the normal distribution. At this time, the driving TFTs of the pixels of the same display panel 10 do not have a large process variation. Also, the digital data of the drain-source current of the driving TFT of each of the pixels P (1,1) to P (m, n) in the (1,1) coordinates to the (m, n) coordinates in the peak white gray scale is obtained. And the drain of the driving TFT of each of the pixels P (1,1) to P (m, n) having coordinates (1,1) to (m, n) at a gray scale other than the peak white gray scale. It can be judged that the degree of deterioration when converting the current between sources into digital data is almost similar. Therefore, the peak white data (PWD) of (1,1) coordinates to (m, n) coordinates are pixels whose normal distribution is (1,1) to (m, n) coordinates at a gray scale other than the peak white gray scale. (P (1,1) to P (m, n)) It can be seen that they closely resemble the normal distribution of values obtained by converting the drain-source current of each driving TFT into digital data. Therefore, the compensation reference data calculator 142 uses the peak white data PWD of (1,1) to (m, n) coordinates as shown in Equation 2 in a gray level other than the peak white gray level (p, q) Compensation reference data CRD (p, q) of coordinates is calculated.

First, the compensation reference data calculator 142 sets the first mask MASK1 in the second data map MAP2 so that the (p, q) coordinates are included. That is, the peak white data of the (p, q) coordinate is included in the first mask MASK1. In FIG. 4C, the first mask MASK1 is described as being a 2 × 2 mask, but the present invention is not limited thereto. The first mask MASK1 may be set as an s × t (s, t is a natural number) mask. When the digital image data RGB (p, q) of the (p, q) coordinates does not correspond to the peak white gradation, the compensation reference data calculator 142 calculates the peak white gradation PG (of the (p, q) coordinates. p, q)) and the grayscale (G (p, q)) of the digital image data of the (p, q) coordinates using the average PM of the peak white data PWM present in the first mask MASK1. Estimate the compensation reference data CRD (p, q) of the (p, q) coordinate at. That is, when the digital image data RGB (p, q) of the (p, q) coordinates does not correspond to the peak white gradation, the compensation reference data calculator 142 calculates the peak white gradation of the (p, q) coordinates. PG (p, q), the average of the peak white data PWD present in the first mask MASK1 is PM, and the gray level of the digital image data of the (p, q) coordinate is G (p, q), (p , q) When the compensation reference data of the coordinate is (CRD (p, q)), the compensation reference data (CRD (p, q)) of the (p, q) coordinate is calculated using Equation 2.

As shown in Equation 2, the compensation reference data CRD (p, q) of the (p, q) coordinate is the average PM of the peak white data PWD present in the first mask MASK1 and (p, q) The value obtained by multiplying the grayscale G (p, q) of the digital image data of the coordinates by the peak white grayscale PG (p, q) of the (p, q) coordinates. The compensation reference data calculator 142 outputs the calculated compensation reference data CRD (p, q) of the (p, q) coordinates to the data compensator 143. (S103, S104)

The data compensator 143 receives compensation reference data CRD (p, q) having a coordinate (p, q) from the compensation data calculator 142. The data compensator 143 may include a look-up table that receives compensation reference data of the (p, q) coordinates as an input address and calculates compensation data of the (p, q) coordinates. To this end, in the look-up table, compensation data (CD (p, q)) of (p, q) coordinates corresponding to 1: 1 with compensation reference data (CRD (p, q)) of (p, q) coordinates are included. Can be stored. The compensation data CD (p, q) of the (p, q) coordinates stored in the look-up table may be previously determined through a preliminary experiment. The data compensator 143 calculates the digital image data RGB (p, q) at the (p, q) coordinate and the compensation data (CD (p, q)) at the (p, q) coordinate as shown in Equation 3 below. To calculate the compensation digital image data RGB '(p, q) at the coordinates (p, q).

As shown in Equation 3, the compensation digital image data RGB '(p, q) at the (p, q) coordinate is divided into the digital image data RGB (p, q) and (p, q) at the (p, q) coordinate. This is the sum of the compensation data CD (p, q) of the coordinates. The data compensator 143 calculates all the compensation digital data RGB '(1,1) to RGB' (m, n) having coordinates of (1,1) to (m, n) and then performs one frame period. To compensate for the digital data RGB 'to the timing controller 130. (S105)

As described above, the present invention calculates the drain-source current of the driving TFT at other gray levels by using the drain-source current of the driving TFT of each pixel measured at the peak white gray level, and the calculated driving The drain-source current of the TFT may be used to compensate digital image data corresponding to other gray levels. As a result, the present invention can be accurately compensated even in low gradation, and can be implemented as a low-capacity memory, thereby reducing the cost.

5 is a table showing PSNR according to degree of deterioration and deterioration correlation. FIG. 5 shows peak signal to noise ratio in case of external compensation (No compensation) and external compensation (No compensation) using the external compensation method of the external compensation circuit 140 according to an embodiment of the present invention. ) Is shown. PSNR refers to the maximum signal-to-noise ratio and represents the power of the noise to the maximum power the signal can have.

Referring to FIG. 5, the degree of deterioration and the deterioration correlation are shown. The degree of deterioration means the degree of deterioration of peak white gradation. Specifically, the degree of deterioration means the difference between the gradation value in the peak white gradation before the driving TFT deteriorates and the gradation value in the peak white gradation after the driving TFT deteriorates. In FIG. 5, 10% (14 gray) means that the degree of deterioration of the driving TFT is 10% in peak white gradation. The deterioration correlation means how much the normal distribution of the peak white gray scale and the normal distribution of the other gray scales resemble each other. As the deterioration correlation is closer to '1', it can be determined that the normal distribution of the peak white gray level and the normal distribution of the other gray levels other than the peak white gray level are more similar.

The present invention estimates the drain-source current of the driving TFT of each of the pixels in the normal distribution of grays other than the peak white gray level from the drain-source current of the driving TFT of each of the pixels in the peak white gray level. Therefore, as shown in FIG. 5, the higher the correlation of deterioration, the higher the compensation effect of the present invention.

As described above, the present invention calculates the drain-source current of the driving TFT at other gray levels by using the drain-source current of the driving TFT of each pixel measured at the peak white gray level, and the calculated driving The drain-source current of the TFT may be used to compensate digital image data corresponding to other gray levels. As a result, the present invention can be accurately compensated even in low gradation, and can be implemented as a low-capacity memory, thereby reducing the cost.

Meanwhile, although an embodiment of the present invention has been described focusing on measuring the drain-source current of the driving TFT of each pixel in the peak white gray level, it should be noted that the present invention is not limited thereto. That is, the exemplary embodiment of the present invention measures the drain-source current of the driving TFT of each pixel corresponding to the predetermined position in the peak white gray level, and then uses the measured drain-source current of the driving TFT to perform other operation. Note that the drain-source current of the driving TFT is calculated in the gray scales, and the digital image data corresponding to the other gray scales can be compensated using the calculated drain-source current of the driving TFT. The pixels corresponding to the predetermined positions may be implemented as pixels positioned in odd lines, pixels positioned in even lines, and pixels positioned in a specific position.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the present invention should not be limited to the details described in the detailed description, but should be defined by the claims.

10: display panel 110: scan driving circuit
120: data driving circuit 130: timing controller
140: external compensation circuit 141: memory
142: compensation reference data calculation unit 143: data compensation unit
150: analog to digital converter

Claims (16)

A display panel including data lines, scan lines, and m × n (m, n is a natural number) pixels formed in a matrix form;
A data driver circuit for supplying peak white data voltages to the data lines; And calculating the drain-source current of the driving TFT from other grayscales by using the drain-source current of the driving TFT of each of the pixels measured in the grayscale to obtain digital image data corresponding to the other grayscales. An external compensation circuit for compensating;
Converts the compensated digital image data into analog data voltages,
And a scan driver circuit for supplying scan signals to the scan lines. 3. The method of claim 2,
When the m × n pixels are represented as pixels of (1,1) to (m, n) coordinates,
A timing controller for controlling the gate driving circuit and the data driving circuit according to a predetermined period to supply a data voltage corresponding to the peak white gray level to each of pixels of (1,1) to (m, n) coordinates. ; And
And an analog-to-digital converter for converting the drain-source current of the driving TFT of each of the pixels of the (1,1) to (m, n) coordinates into digital data. 3. The method of claim 2,
The external compensation circuit,
And a memory configured to store peak white data of (1,1) to (m, n) coordinates converted from the analog-digital converter. The method of claim 3, wherein
The external compensation circuit,
(p, q) (p is a natural number satisfying 1≤p≤m, q is a natural number satisfying 1≤q≤m) When the digital image data of coordinates corresponds to the peak white gray scale, (p, q) And a compensation reference data calculator for selecting peak white data of the coordinates as compensation reference data of the (p, q) coordinates. 5. The method of claim 4,
The compensation reference data calculator,
Arrange the digital image data of the (1,1) to (m, n) coordinates to create a first data map, and arrange the peak white data of the (1,1) to (mn) coordinates to form a second data map. And a first mask is set in the second data map to include the (p, q) coordinates. The method of claim 5, wherein
The compensation reference data calculator,
If the digital image data of the (p, q) coordinates do not correspond to the peak white gray level, the peak white gray level of the (p, q) coordinates is PG (p, q), the peak white present in the second mask. If the average of the data is PGM, the gray level of the digital image data of the (p, q) coordinate is G (p, q), and the compensation reference data of the (p, q) coordinate is CRD (p, q).

The organic light emitting diode display device of claim 1, wherein the reference data of the (p, q) coordinates is calculated. The method according to claim 6,
The external compensation circuit,
Compensation data of (p, q) coordinates is calculated from the compensation reference data of (p, q) coordinates, and digital image data of the (p, q) coordinates and compensation data of the (p, q) coordinates are calculated. And a data compensator for outputting compensation digital image data of the (p, q) coordinates. The method of claim 7, wherein
The data compensation unit,
And a look-up table which receives the compensation reference data of the (p, q) coordinates as an input address and calculates the compensation data of the (p, q) coordinates. A driving method of an organic light emitting diode display device comprising a display panel including data lines, scan lines, and m × n pixels (m and n are natural numbers) formed in a matrix form.
(A) By using the drain-source current of the driving TFT of each of the pixels measured at the peak white gray level, the drain-source current of the driving TFT is calculated at other gray levels to correspond to the other gray levels. Compensating for the digital image data;
(B) converting the compensated digital image data into analog data voltages, and supplying the data voltages to the data lines; And
And (C) supplying scan signals to the scan lines. The method of claim 9,
When the m × n pixels are represented as pixels of (1,1) to (m, n) coordinates,
(D) supplying a data voltage corresponding to the peak white gray level to each of pixels having a (1,1) to (m, n) coordinate according to a predetermined period; And
(E) a method of driving an organic light emitting diode display device further comprising converting the drain-source current of the driving TFT of each of the pixels having the (1,1) to (m, n) coordinates into digital data. . 11. The method of claim 10,
The step (A)
(A-1) storing peak white data of the (1,1) to (m, n) coordinates in a memory. The method of claim 11,
The step (A)
(A-2) When the digital image data of the coordinate (p, q) (p is a natural number satisfying 1≤p≤m, q is a natural number satisfying 1≤q≤m) corresponds to the peak white gray scale, and selecting peak white data of (p, q) coordinates as compensation reference data of (p, q) coordinates. 13. The method of claim 12,
The step (A)
(A-3) Arrange the digital image data of the (1,1) to (m, n) coordinates to create a first data map, and the peak white data of the (1,1) to (mn) coordinates. And arranging the first and second data maps, and setting a first mask to the second data map to include the (p, q) coordinates. . The method of claim 13,
The step (A)
(A-4) When the digital image data of the (p, q) coordinates do not correspond to the peak white gray level, the peak white gray level of the (p, q) coordinates is PG (p, q) and the second mask. The average of the peak white data present in the PGM, the gray level of the digital image data of the (p, q) coordinates G (p, q), the compensation reference data of the (p, q) coordinates CRD (p, q) Say,

Calculating compensation reference data of the (p, q) coordinates by using the organic light emitting diode display device. 15. The method of claim 14,
The step (A)
(A-5) Compensation data of (p, q) coordinates is calculated from the compensation reference data of the (p, q) coordinates, and the digital image data of the (p, q) coordinates and the (p, q) coordinates And a data compensator for calculating compensation data and outputting compensation digital image data of the (p, q) coordinates. The method of claim 15,
Step (A-5),
And receiving compensation reference data of the (p, q) coordinates as an input address of a look-up table to calculate compensation data of the (p, q) coordinates.

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