JP2008309895A - Display device and display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device capable of estimating and correcting the luminance according to used records obtained by actually causing electric current to flow through an organic EL element, in particular, by taking the consumed electric current into account based on a luminance life estimation characteristic of the organic EL element which is known beforehand, without disposing a specified photoreception element for luminance measurement in respect to the display device having a display part having the organic EL element. <P>SOLUTION: A control part calculates the used records in terms of electric current time product always in usage of the organic EL element at every pixel. Pixels in which the used record value exceeds a prescribed value are decided as degraded pixels (B). It is decided whether the degraded pixels are a degraded pixel assembly or degraded single pixels and only the degraded pixel assembly is made to be a correction object pixel. When the image data of (C) are displayed, the image data is displayed on the organic EL element as display data while raising the gradation of pixels of only the degraded pixel assembly which is made to be the correction object pixel and, thereby, is made to be an inconspicuous display as seen in (E) and, at the same time, an increase of the consumed electric current can be suppressed more than heretofore. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a self-luminous display device and a display panel, and more particularly, to correction of a burn-in phenomenon caused by a decrease in luminance over time.

There is a display device including a light receiving element that measures light emission luminance of an EL (electroluminescence) element (for example, see Patent Document 1). In the display panel 110a of FIG. 2 of Patent Document 1, a measurement light receiving element PD is provided for each EL element OEL of each pixel. Then, in the external circuit of the display panel 110a, the gradation of the display data is corrected based on the measured luminance value, so that the initial luminance is restored and the variation in the emission luminance between the pixels is corrected.
This display panel 110a has five signal lines Vscan, FL, VR, DL, and VL (Vdd) except for GND as signal lines necessary for each pixel. For each pixel, five transistors are used as an active circuit.

  In addition, there is a display device including a photosensor that measures light emission luminance of an EL element (see, for example, Patent Document 2). In FIG. 3 of Patent Document 2, the display unit 21 is provided with a measurement photosensor for each organic EL element of each pixel. In the display unit 21, the same data signal Vdata is given by analog processing to reduce the light emission amount of the organic EL element 7 in accordance with the magnitude of the brightness, and the pixel is brought closer to a pixel having a lower brightness as a whole. As a result, luminance unevenness is corrected in the direction of reducing power consumption.

In addition, there is a self-luminous display device that does not have a light-receiving element for measurement (see, for example, Patent Document 3). In the display device disclosed in Patent Document 3, a plurality of image data having the same meaning is switched to prevent the same light emitting element from emitting light, thereby reducing burn-in. In addition, there is a description of a method of displaying the image negative / positive in reverse with a predetermined cycle, or shifting the display position of the image by several dots with a predetermined cycle.
Japanese Patent Laying-Open No. 2005-92028 (pages 10 to 22 and FIGS. 2 to 5) JP 2006-30317 A (pages 8-10, FIG. 3) JP 2004-264751 A (pages 8 to 10, FIGS. 1 to 5)

  In the display device of Patent Document 1, the number of signal lines per pixel is as many as five except for GND. In addition, the number of transistors per pixel is as large as five. There is a problem that they block a part of the light emission path of the EL element and the aperture ratio becomes low. In addition, since the gradation data of the deteriorated pixel is increased, that is, the light emission current is increased to return to the initial luminance, there is a problem that the current consumption increases.

In the organic EL display device of Patent Document 2, the amount of light emitted from the organic EL element 7 is reduced in accordance with the magnitude of the brightness, and the pixel as a whole is brought closer to the lower brightness. As a result, the luminance unevenness is corrected, but it is corrected so that the entire screen becomes darker.
In the display device of Patent Document 3, since a plurality of image data (for example, icons) having the same meaning and different patterns are switched, there is a sense of incongruity even if the user interprets the same meaning.

  An object of the present invention is to provide a display device and a display panel in which deterioration of an EL element is not noticeable. Specifically, an object of the present invention is to increase the aperture ratio of light emission of an EL element by reducing the number of signal lines and the number of transistors per pixel in a method in which a light receiving element for measurement is provided and corrected by an external circuit. Another object of the present invention is to perform an optimal correction in consideration of current consumption.

  In order to achieve the above object, a display device of the present invention is a display device having a display unit in which a plurality of light emitting pixels are arranged and a control unit for controlling the display unit, and the control unit includes the light emitting pixel. A prediction characteristic of the light emission luminance associated with the use history value at the reference light emission current and a second use history value in which the use history value is reduced to a predetermined second light emission luminance in comparison with the initial first light emission luminance in advance. Life characteristic storage means for storing, light emission result calculating means for calculating the use result value for displaying the video data for each light emitting pixel of the display means, and storing the result in the light emission result storage means, and the use result value of the light emission result storage means And a correction unit that increases the gradation of the portion corresponding to the set pixel and displays the video data on the display unit when it is determined that the pixel exceeds the second use history value and is a set pixel. The And butterflies.

  In the display panel of the present invention, a pixel portion is arranged at each coordinate position of a matrix intersection of a plurality of columns and a plurality of rows, and each pixel portion is controlled by a signal on a control line wired in the matrix shape. Each of the pixel units receives light emitted from the light emitting element and the light emitting element, and transmits a light reception signal to a pixel unit at a first diagonally adjacent coordinate position adjacent to the pixel unit in one diagonal direction. A light receiving element, and a receiving unit that receives a light receiving signal transmitted from the light receiving element of the pixel portion at the second diagonally adjacent coordinate position adjacent to the opposite direction of the diagonal one direction of the pixel unit, and the control line includes Each column has a first column control line and a second column control line, and each row has a first row control line and a second row control line. Column control line, second column control line, first row control line and second row control The light emitting element of the pixel portion at the coordinate position of the intersection of the column and the row emits light by the signal of the line, the light emission is received by the light receiving element of the pixel portion, and the light receiving signal is received by the pixel portion of the first oblique adjacent coordinate position. The first column control line, the second column control line, and the first row control for each of the columns and rows corresponding to the coordinates of the pixel portion at the first obliquely adjacent coordinate position with respect to the light emitting pixel portion that emits light. The light receiving signal of the light receiving element of the light emitting pixel portion is read for light emission correction of the light emitting element of the light emitting pixel portion by the signal of the line and the second row control line.

  According to the present invention, it is possible to provide a display device in which deterioration of an EL element is not noticeable. In addition, in a method in which a light receiving element for measurement is provided and correction is performed by an external circuit, the number of signal lines and the number of transistors per pixel can be reduced to increase the light emission aperture ratio of the EL element. In addition, it is possible to perform optimal correction in consideration of current consumption.

  Each example will be described below.

  Example 1 is an example in which a light emitting element and a light receiving element are provided in one pixel. The light emission of the light emitting element is received by the light receiving element arranged in the same pixel portion, but the light reception signal from the light receiving element is read out by the active circuit or signal line in the pixel portion at an oblique coordinate position of the pixel. It is characterized by performing by.

  FIG. 1 is a block diagram of a display device according to Embodiment 1 of the present invention. The display device 100 includes a video storage unit 21, a measured luminance storage unit 22, an initial luminance storage unit 23, a control unit 24, a video controller 25, a column control unit 30, a row scanning control unit 50, a display panel 60, and the like. Further, the column control unit 30 includes a signal driver / receiver 31 and a current supply driver 32. The row scanning control unit 50 includes a light receiving scanning driver 51 and a writing / reading scanning driver 52.

  The video storage unit 21 stores an image source to be displayed on the display panel 60. The measured brightness storage unit 22 stores the brightness measurement result of each pixel of the display panel 60. The initial luminance storage unit 23 stores the luminance measurement result of each pixel of the display panel 60 before shipment from the factory or at the start of use of the display device 100. The control unit 24 includes a CPU, a ROM, a RAM, an I / O, and the like, and controls the entire display device 100. The video controller 25 controls the column control unit 30 and the row scanning control unit 50 to perform writing of video data to the display panel 60, reading of received light data obtained by measuring the luminance of each pixel, and the like.

  The column controller 30 controls the column X (column X = 1 to m) of the display panel 60. The row scanning control unit 50 controls the row Y (row Y = 1 to n) of the display panel 60. The display panel 60 is a pixel portion having a matrix structure with columns X = 1 to m and rows Y = 1 to n.

FIG. 2 is a block diagram of the column control unit of the display device according to the first embodiment of the present invention. The column control unit 30 (the signal driver / receiver 31 and the current supply driver 32) controls the column X (column X = 1 to m) of the display panel 60.
The signal driver / receiver 31 is a bidirectional buffer. As a driver, the video data transmitted from the video controller 25 is distributed to each column by the video analog output 33, D / A converted, and sent as an analog light emission signal (video signal) via the 3-state driver 37. Thus, column light signals 1 to m (first column control line) of the signal lines are supplied to the display panel 60.

  The signal driver / receiver 31 reads, as a receiver, a light reception signal obtained by measuring the luminance of each pixel of each column of the display panel 60 from the column light signal 1 to the column light signal m of the signal line, and outputs the received light signal by the three-state receiver 36. In addition, it is converted to digital by the A / D converter 35 and transmitted to the video controller 25 as received light data.

  The timing control 34 controls the three-state driver 37 by outputting outputs 1 to m, which are column selection signals for light emission, based on the column control data from the video controller 25. Further, detection 1 to detection m, which are selection signals for light receiving columns, are output to control the 3-state receiver 36.

  The current supply driver 32 supplies current to the organic EL for each column of the display panel 60 to emit light. The timing control 38 outputs a column current supply selection signal for light emission in accordance with the column control data from the video controller 25 and controls the buffer 39 on and off. The buffer 39 is turned on and off, and supplies the output of the GND level or the Vh level to the display panel 60 through the column current supply 1 to the column current supply m (second column control line) of the signal line. When the Vh level is output, a current for light emission is supplied to the organic EL of the display panel 60.

  The timing control 34 and the timing control 38 may be a random logic circuit or a sequencer. The 3-state receiver 36 and the 3-state driver 37 may be analog switches or the like.

FIG. 3 is a block diagram of the row scanning control unit of the display device according to the first embodiment of the present invention. The row scanning control unit 50 (the light receiving scanning driver 51 and the writing / reading scanning driver 52) controls the row Y (row Y = 1 to n) of the display panel 60.
The light reception scanning driver 51 reads the light reception signal obtained by measuring the luminance of each pixel of the display panel 60 from the column light signal 1 to the column light signal m (FIG. 2) of the signal line. ) Is controlled. The timing control 53 selects a row Y (row Y = 1 to n) and turns the buffer 54 on and off. The buffer 54 is turned on and off, and supplies the output of the GND level or the Vh level to the display panel 60 by the row light receiving scan 1 to the row light receiving scan n (first row control line) of the signal lines.

  When the buffer 54 outputs the Vh level, the light receiving signal measured by the light receiving element is charged into the capacitor inside the display panel 60. When the GND level is output, the light receiving signal is not charged into the capacitor.

  The writing / reading scanning driver 52 writes a light emission signal (video signal) to each pixel of the display panel 60 or reads a light reception signal of each pixel with respect to the row Y (row Y = 1 to n). The timing control 55 selects a row Y (row Y = 1 to n) and turns the buffer 56 on and off. The buffer 56 is turned on / off, and supplies the output of the GND level or the Vh level to the display panel 60 through the signal line row write / read scan 1 to the row write / read scan n (second row control line).

  When the buffer 56 outputs the Vh level, writing or reading is performed. When the GND level is output, neither writing nor reading is performed.

  FIG. 4 is a circuit diagram of the display panel of the display device according to the first embodiment of the present invention. A part of 2 × 2 pixels G1 to G4 of the display panel 60 is illustrated. This is a matrix of two columns of arbitrary column X and column X + 1 and two rows of arbitrary row Y and row Y + 1. X is any column from 1 to m, and Y is any row from 1 to n.

  A portion separated by a dotted line is an area of each pixel. Each of the pixels G1, G2, G3, and G4 includes four transistors, a transistor J (first transistor), a transistor K (second transistor), a transistor T (third transistor), and a transistor U as active circuits. Transistors are arranged. In each region, a capacitor C, an organic EL light emitting element E, a light receiving element P (Photo Sensor), and a resistor R are arranged.

  Within the same pixel portion, the light emission amount of the light emitting element E is measured by the light receiving element P as indicated by a zigzag arrow. This structure is similar to, for example, a structure in which a part of light emission of the organic EL layer (62) disclosed in FIG. 6 and page 20 of JP-A-2006-58352 is directly received by the light receiving element (PS). Detailed description is omitted.

  The optical path for light reception indicated by the zigzag arrow is completed within each pixel. For example, the light emission of the light emitting element E in the pixel G2 region reaches only the light receiving element P in the pixel G2 region as a light receiving optical path. Between the light receiving elements of other pixels, the light receiving light path is shielded.

  The signal lines wired to each pixel unit are, except for GND, a column optical signal for column control (first column control line) and a column current supply (second column control line) for each pixel unit. In addition, a total of four line light receiving scans (first row control lines) for row control and row write / read scans (second row control lines) are wired. For example, for the pixel G1, the column light signal X, the column current supply X, the row light receiving scan Y, and the row write / read scan Y corresponding to the column and row coordinates (X, Y). For the pixel G2, the column light signal X + 1, the column current supply X + 1, the row light receiving scan Y, and the row write / read scan Y corresponding to the column and row coordinates (X + 1, Y). For the pixel G3, the column light signal X, the column current supply X, the row light receiving scan Y + 1, and the row write / read scan Y + 1 corresponding to the column and row coordinates (X, Y + 1). For the pixel G4, the column optical signal X + 1, the column current supply X + 1, the row light receiving scan Y + 1, and the row write / read scan Y + 1 corresponding to the column and row coordinates (X + 1, Y + 1).

  Each pixel is controlled by a signal line of the coordinates of each pixel. Reading of the light reception signal from the light receiving element P is performed by a signal line of coordinates different from the coordinates of each pixel. This is the greatest feature of the first embodiment.

  For example, the light emission amount of the light emitting element E in the pixel G2 region is measured by the light receiving element P in the same pixel G2 region, and a current corresponding to the light amount is generated from the right to the left in the figure. However, the wiring of the light receiving element P is led to the transistor T and the resistor R in the pixel G3 region at the coordinate position diagonally lower left of the pixel G2. Then, the light reception signal of the light receiving element P in the pixel G2 region is read out to the outside through the signal line of the coordinates of the pixel G3.

  Similarly, the light receiving signal from the light receiving element P in the pixel region at the upper right diagonal coordinate position is wired to the transistor T and the resistor R in the pixel G2 region.

  These correlations are applied to all the pixels, and as shown in the figure, the wiring of the light receiving element P of each pixel is led to the resistance R of the pixel portion at the coordinate position diagonally to the lower left of each pixel.

  The light receiving element P requires wiring to the lower left diagonal coordinates, but is the wiring with the shortest diagonal distance, and unlike the signal lines for the column control and row control, the light emission of the light emitting element E does not affect the aperture ratio reduction. rare.

  Although this wiring has a lower left diagonal coordinate position, it may be any of the upper left diagonal, upper right diagonal, or lower right diagonal as long as all pixels are in a unified direction. You may make it read outside by a line.

[Operation of each pixel]
Next, details of the operation of the signal lines and components in each pixel will be described.
The column light signal is a bidirectional analog signal. At the time of light emission, an analog light emission signal (video signal) from the signal driver / receiver 31 (FIG. 2) is written to the capacitor C via the transistor J. The EL light emission that is held and matches the gradation of the light emission signal (video signal) is performed. At the time of light reception, the light reception signal of the measurement result of the pixel in the upper right diagonal direction is read out to the signal driver / receiver 31 via the transistor J and the column light signal in the reverse direction. The transistor J is used both for writing the light emission signal (video signal) to the capacitor C and for reading the light reception signal.
The column current supply supplies current to the organic EL for light emission at the Vh level.

  In the row light receiving scanning, the transistor T is turned on and the transistor U is turned on when the row light receiving scanning is at the Vh level and the column current supply is at the GND level. Then, a current corresponding to the amount of light received measured by the light receiving element P of the diagonally upper right pixel flows through the resistor R, and a voltage corresponding to the current is obtained as a light reception signal. This light reception signal is supplied to the transistor J via the transistor T.

  In the row writing / reading scans 1 to 3, the transistor J is turned on at the Vh level, and the light emission signal (video signal) is written to the capacitor C. Further, the transistor J is turned on at the Vh level, and the light reception signal from the transistor T is read out.

[Overall operation]
The overall operation will be described with reference to FIGS.
[Light emission]
First, light emission will be described with respect to the pixel G2 at coordinates (X + 1, Y).
(Light emission step 1: Start of light emission operation of the light emitting element E)
The column control unit 30 (FIG. 2) supplies an analog light emission signal (video signal) from the column light signal X + 1 to the signal line of the column and row coordinates (X + 1, Y) of the pixel G2. Column current supply X + 1 = Vh level. Further, the row scanning control unit 50 (FIG. 3) sets the row light receiving scanning Y = GND level and the row writing / reading scanning Y = Vh level.

  In this state, in the pixel G2, the transistors J and K are on, and the transistors T and U are off. As a result, an analog light emission signal (video signal) from the column light signal X + 1 flows from the left to the right of the transistor J to charge the capacitor C. A current corresponding to the charge voltage of the capacitor C flows from the column current supply X + 1 = Vh level to the light emitting element E via the transistor K, and emits light with a luminance corresponding to the light emission signal (video signal).

(Light emission step 2: Hold of light emission operation of light emitting element E)
Next, the row scanning control unit 50 drops the row writing / reading scanning Y to the GND level, the transistor J is turned off, and the charge of C is held as it is. The column controller 30 continues the column current supply X + 1 = Vh level. In this state, only the transistor K is on in the pixel G2. Thus, a current corresponding to the charge voltage of the capacitor C continuously flows from the column current supply X + 1 = Vh level to the light emitting element E via the transistor K, and the same luminance is continuously emitted. In a normal image display process, this process is continued for one frame of the image.

[Brightness measurement]
Next, an operation for measuring the light emission luminance of the issuing element E of the pixel G2 will be described. Light emission of the issuing element E of the pixel G2 is received by the light receiving element P of the pixel G2. The wiring of the light receiving element P is led to the resistor R of the pixel G3 at the coordinate position diagonally inclined to the lower left of G2.

For the pixel G2 (X + 1, Y), the column control unit 30 and the row scanning control unit 50 continue the above-described (light emission step 2: hold of the light emission operation of the light emitting element E).
Reading of the received light signal is performed by a signal line having the coordinates (X, Y + 1) of the column and row of the pixel G3. The column control unit 30 turns off the three-state driver 37 for the column optical signal X to enter the input state by the three-state receiver 36. Further, the column current supply X is set to the GND level. The row scanning control unit 50 sets the row light receiving scanning Y + 1 = Vh level and the row writing / reading scanning Y + 1 = Vh level.

  Thereby, the transistors J, T, and U of the pixel G3 are turned on, and the transistor K is turned off. The light emitting element E of the pixel G3 does not emit light. The light receiving element P of the pixel G2 receives light emitted from the light emitting element E of the pixel G2 and passes a current corresponding to the amount of received light to the resistor R and the transistor U of the pixel G3. The voltage generated in the resistor R is output as a light reception signal to the column light signal X via the transistors T and J from the right to the left.

  The column control unit 30 turns on only the elements corresponding to the column X of the three-state receiver 36, reads the received light signal of the column light signal X, converts it by the A / D converter 35, and converts it into the received light data as the video controller 25. (FIG. 1). Then, it is recorded in the measured luminance storage unit 22 as emission luminance data of the pixel G2. It should be noted that in the initial stage of starting use, the initial luminance data is recorded in the initial luminance storage unit 23.

  In the pixel G4 at the coordinate position where the column X + 1 of the pixel G2 and the row Y + 1 of the pixel G3 intersect, the column current supply X + 1 = Vh level, the row light receiving scan Y + 1 = Vh level, and the row write / read scan Y + 1 = Vh level. Therefore, the light emitting element E of the pixel G4 may emit light unintentionally, but this light emission does not affect the light receiving element P of the pixel G2, and there is no problem.

Further, in the case of normal image display that is not luminance measurement, the row light reception scanning is always at the GND level, so that unintended pixels do not emit light.
This completes the measurement of the light emission luminance of the pixel G2. The same processing is performed for all pixels, and the measurement of light emission luminance for all pixels is completed.

  Note that a plurality of pixels may be measured at the same time instead of measurement for each pixel. For example, every second pixel in the row Y, the pixel G2 (X + 1, Y), the pixel (X + 3, Y) (not shown), the pixel (X + 5, Y) (not shown), and the like are caused to emit light simultaneously. Then, simultaneous measurement is performed using the signal lines of the coordinates (X, Y + 1), coordinates (X + 2, Y + 1), and coordinates (X + 4, Y + 1) of the pixel G3 at the coordinate position of the lower left diagonal of these pixels. The received light signal is simultaneously output from the column light signal X, the column light signal X + 2, and the column light signal X + 4 to the signal driver / receiver 31 (FIG. 2). The signal driver / receiver 31 multiplexes the plurality of column optical signals, A / D converts them in time series, and sends them as received light data.

[Correction in normal image display]
Next, processing for correcting light emission based on the above-described measured light emission luminance in normal image display will be described.
At the factory shipment stage of the display device 100 or the user's first stage of use, a setter, a user, or the like measures the light emission luminance and gives an operation instruction to record it in the initial luminance storage unit 23 as the initial luminance. The control unit 24 records this in the initial luminance storage unit 23. At this time, although the absolute value varies slightly due to variations in the light emission luminance of each pixel and the sensitivity of the light receiving element, the initial value is stored as 100% for each pixel. This data is not rewritten thereafter.

  Next, after starting to use the display device 100, the control unit 24 repeats remeasurement at an appropriate time. It can be daily, weekly, or monthly. The data is recorded in the measured luminance storage unit 22 and is overwritten and recorded every time remeasurement is performed.

  The control unit 24 calculates the ratio of the remeasured luminance to the initial luminance for each pixel, and records it as a ratio storage unit in another area of the measured luminance storage unit 22. For example, the pixel G2 is recorded with a ratio of 95%.

  Next, in the normal image display, the control unit 24 gradually calculates the gradation data of each pixel of the video source to be displayed in the video storage unit 21 by the ratio of the corresponding pixel in the measured luminance storage unit 22. For example, the gradation data of the pixel G2 is divided by a ratio of 95% to correct the gradation so that the gradation becomes bright, and the corrected data is used as video data. Thereby, the initial light emission luminance can be reproduced. The degree of correction may be adjusted as appropriate without returning to the initial light emission luminance.

  In the first embodiment, with respect to the light emitting pixels, the measurement is performed by reading the received light signal using the signal line at the coordinate position of the lower left diagonal. Therefore, it is impossible to measure the light emission luminance of the pixel group in the leftmost column and the pixel group in the lowermost row. Therefore, the pixel group is arranged as a dummy pixel only for reading the received light signal without light emission. That is, the transistor K, the light-emitting element E, and the light-receiving element P may not be provided or are not used.

  Alternatively, if the light emission frequency of the pixel group at the extreme end is low in normal image display, there is no need to worry about deterioration, and the light emission pixel may be used without correction. That is, the light receiving element P may not be provided or is not used.

  In the first embodiment, the light receiving element receives light emitted from the light emitting element, but may receive light outside the display panel 60. Therefore, by measuring the light reception signal of the light receiving element without causing the light emitting element to emit light, the amount of external light received can be determined, and the influence can be taken into account as the background luminance.

  For example, the light emission luminance of the light emitting element can be accurately measured by performing an operation of subtracting the amount of external light received from the amount of light received when the light emitting element emits light. Alternatively, the light emission luminance of the light emitting element may not be measured when the amount of external light received is a certain level or more. Alternatively, when applied to a foldable portable terminal or the like, the display panel 60 is covered and darkened in a folded state, and therefore measurement may be performed under the conditions.

  According to the first embodiment of the present invention, the signal line per pixel of the display device of the conventional patent document 1 is 5 except for GND, and the number of transistors per pixel is 5 as compared to the signal line. The number of lines can be four and the number of transistors can be four except for GND, so that the aperture ratio of light emission of the EL element can be increased.

  Example 2 does not have a special light-receiving element for measuring luminance, and corrects by predicting the luminance based on the actual usage of current flowing through the organic EL based on the known luminance lifetime characteristics of the organic EL. In particular, the luminance is corrected in consideration of current consumption.

FIG. 5 is a diagram illustrating the luminance life characteristics of the organic EL according to Example 2 of the present invention.
(A) is a characteristic curve representing the luminance life of the organic EL. The horizontal axis is the current time product obtained by accumulating the product of the current value passed through the organic EL and the light emission time, and the vertical axis is the light emission luminance under the same current I1 condition. That is, the lifetime deteriorates as the current increases and as the current flow time accumulates, and the luminance gradually decreases continuously. This life curve is obtained in advance as experiments or manufacturer data.

  Several points along the way will be described. The organic EL emits light having an initial luminance of 100% with respect to the current I1 in the current time product T1 at the beginning of use. It gradually deteriorates as it is used, and in the current-time product T2, the luminance decreases even at the same current I1, and only more than 93% is emitted. In the current-time product T3, the luminance is 93% at the same current I1. In the current time product T4, the luminance is 90% at the same current I1. In the current time product T5, the luminance is 87% at the same current I1.

  (B) is a characteristic curve of light emission luminance when the current passed through the organic EL is changed. The current-time product T1 at the beginning of the use of the organic EL has a T1 characteristic indicated by a thick line, emits light with an initial luminance of 100% at the current I1, and has a luminance on the thick line T1 characteristic when the current is changed. Changes.

  When the current-time product reaches T2, the organic EL deteriorates to have a thick line T2 characteristic, and emits light with a luminance exceeding 93% at the same current I1. When the current is changed, the luminance changes on the thick line T2 characteristic.

  When the current-time product reaches T3, the organic EL further deteriorates to become a thick line T3 characteristic and emits only 93% of luminance at the same current I1. When the current is changed, the luminance changes on the thick line T3 characteristic.

  When the current-time product reaches T4, the organic EL further deteriorates to become a thick line T4 characteristic, and only the luminance of 90% is emitted with the same current I1. When the current is changed, the luminance changes on the thick line T4 characteristic.

  When the current-time product reaches T5, the organic EL further deteriorates to become a thick line T5 characteristic, and the luminance is only 87% at the same current I1. When the current is changed, the luminance changes on the thick line T5 characteristic.

  These thick characteristic curves are obtained in advance as data for a life test or the like. For example, T1 (luminance 100% at current I1), T2 (luminance greater than 93% at current I1), T3 (luminance 93% at current I1), T4 (luminance 90% at current I1), T5 (luminance at current I1) 87%) The characteristics are illustrated, but the luminance at current I1 is 99%, 98%, 97%, 96%, 95%, 94%, 93%, 92%, 91%,. Each characteristic curve may be provided in advance.

Next, a display image example will be described.
FIG. 6 is a diagram illustrating a display screen of the organic EL display unit of the display device according to the second embodiment of the invention. The current-time product of each pixel constituting the organic EL display unit differs for each pixel depending on the image to be displayed. Therefore, the degree of deterioration of each pixel will be different. It is recognized as so-called burn-in.

  For example, since icon image data such as (A) is often displayed on a display device at all times, deterioration of the pixels in the icon display portion is likely to proceed. Further, depending on various images, a pixel having deteriorated is generated.

  (B) is a screen when full-screen white image data is displayed in a state in which deterioration has progressed. A deteriorated pixel aggregate such as an icon or a deteriorated single pixel is generated. In the state in which the deterioration has progressed, even if the portion is pure white image data, the luminance is reduced and the display becomes light gray, which is recognized as burn-in.

  (C) is image data of a white puppy. (D) is a screen on which the image data of (C) is displayed in a state in which deterioration has progressed as in (B). The deteriorated image is recognized in the white puppy part.

  A subjective evaluation test using a human visual system was performed to determine how much this burn-in is recognized by human eyes. As a result, it was found that the burn-in was inconspicuous when the luminance was 93% or higher with respect to the initial luminance of 100% that did not deteriorate.

  (E) and (F) are screens displaying the image data of (C) after performing the burn-in correction according to the second embodiment of the present invention in a state in which the deterioration is advanced as in (B). 7 and FIG.

  FIG. 7 is a block diagram of a display device according to Embodiment 2 of the present invention. The display device 200 includes a control unit 70, an organic EL display unit 90, and the like. The control unit 70 calculates video data for correcting the deterioration of the organic EL, and supplies the corrected video data to the organic EL display unit 90.

  The control unit 70 includes a light emission result calculation unit 71, an all-pixel light emission result storage unit 72, a life prediction characteristic storage unit 73, a deteriorated pixel extraction unit 74, a deteriorated pixel storage unit 75, a correction target pixel extraction unit 76, and a correction target pixel storage unit. 77, a current VS luminance prediction characteristic storage unit 78, a correction coefficient calculation unit 79, an all-pixel correction coefficient storage unit 80, a video storage unit 81, a multiplier 82, and the like.

  The light emission result calculation unit 71 calculates the current-time product of each pixel based on corrected video data that is data displayed on the organic EL display unit 90 at all times while the organic EL display unit 90 is used, Recorded in the light emission record storage unit 72 for each pixel. The corrected video data is gradation data, and the gradation correlates with the current value flowing through the organic EL. The life prediction characteristic storage unit 73 is a memory in which the life characteristic shown in FIG.

  The deteriorated pixel extraction unit 74 extracts a pixel having a luminance of less than 93%, that is, a current-time product exceeding T3 for each pixel of the all-pixel light emission result storage unit 72, and stores the deterioration pixel together with the light emission result for each pixel. Store in the unit 75. Since the deterioration of the organic EL does not proceed rapidly, the deteriorated pixel extraction unit 74 may perform processing at intervals of, for example, one day, one week, or one month.

  The correction target pixel extraction unit 76 corrects which of the deteriorated pixels (less than 93%) is triggered by the deterioration pixel (less than 93%) stored in the deteriorated pixel storage unit 75 as a trigger. Is extracted and stored in the correction target pixel storage unit 77 together with the emission results for each pixel. The operation of the correction target pixel extraction unit 76 will be described in detail later with reference to an operation flowchart (FIG. 8).

The current VS luminance prediction characteristic storage unit 78 is a memory in which the current VS luminance prediction characteristic of FIG.
For each deteriorated pixel in the correction target pixel storage unit 77, the correction coefficient calculation unit 79 emits light of the pixel and the corresponding characteristic of the current VS luminance prediction characteristic storage unit 78 corresponding to the light emission performance (FIG. 5B). Based on the above, a correction coefficient is calculated and stored in the all-pixel correction coefficient storage unit 80. The operation of the correction coefficient calculation unit 79 will be described in detail later with reference to operation flowcharts (FIGS. 9 and 10).

  Since the deterioration of the organic EL does not proceed rapidly, the processes of the deteriorated pixel extraction unit 74, the correction target pixel extraction unit 76, and the correction coefficient calculation unit 79 described above are, for example, one day, one week, one month, etc. Processing may be performed at intervals.

  The video storage unit 81 is a storage unit for a video source to be displayed on the organic EL display unit 90. When the organic EL display unit 90 is used, the multiplier 82 always multiplies each pixel of the video data in the video storage unit 81 by the correction coefficient for each pixel in the all-pixel correction coefficient storage unit 80 to provide a corrected video. Data is created and transmitted to the organic EL display unit 90. The organic EL display unit 90 displays an appropriate luminance by causing each pixel to pass a current corresponding to the corrected video data.

FIG. 8 is an operation flowchart of the correction target pixel extraction unit according to the second embodiment of the present invention.
FIG. 8A illustrates a correction target pixel extraction method 1 according to the second embodiment. In this correction target pixel extraction method 1, a deteriorated pixel aggregate excluding deteriorated single pixels from the deteriorated pixels is extracted and set as a correction target.

  The correction target pixel extraction unit 76 checks whether or not a deteriorated pixel (luminance less than 93%) is stored in the deteriorated pixel storage unit 75 (step S11). If there is a degraded pixel having a luminance of less than 93%, it is checked whether the pixel is a degraded pixel aggregate or a degraded single pixel (step S12).

  The determination as to whether it is an aggregate or single is made by determining whether or not a predetermined number of deteriorated pixels are arranged continuously. Thereby, for example, in the case of the deterioration state as shown in FIG. 6B, if deterioration progresses when the collective pixel is always displayed as in the icon display, it is detected as a deteriorated pixel aggregate, and the pixel Is recorded in the correction target pixel storage unit 77 (step S13). The deteriorated single pixel in FIG. 6B is not recorded in the correction target pixel storage unit 77.

  Only the deteriorated pixel aggregate recorded in the correction target pixel storage unit 77 is subjected to the luminance enhancement correction process of the correction coefficient calculation unit 79 described later (FIGS. 9 and 10). As a result, FIG. As shown in FIG. 5B, only the deteriorated single pixel is displayed as a burn-in while the deterioration of the icon portion is not visible.

  According to the correction target pixel extraction method 1 of the second embodiment, the deteriorated single pixel itself is inconspicuous to the human eye, so it does not matter. In addition, the luminance improvement process is a process that increases the current consumption of the power supply. However, by not correcting the degraded single pixel, it is possible to suppress an increase in the consumption current due to the degradation correction.

  FIG. 8B illustrates a correction target pixel extraction method 2 according to the second embodiment. In this correction target pixel extraction method 2, a predetermined number of deteriorated pixels are randomly selected from the deteriorated pixels to be corrected.

  The correction target pixel extraction unit 76 checks whether or not a deteriorated pixel (luminance less than 93%) is stored in the deteriorated pixel storage unit 75 (step S21). If there is a degraded pixel having a luminance of less than 93%, for example, 90% of the degraded pixels are randomly extracted and recorded in the correction target pixel storage unit 77 as correction targets (step S22). The remaining 10% is not subject to correction.

  Only the 90% number of deteriorated pixels recorded in the correction target pixel storage unit 77 is subjected to the luminance enhancement correction process of the correction coefficient calculation unit 79 described later (FIGS. 9 and 10). As shown in FIG. 6F, the display is performed in a state where 90% of the deteriorated pixels are not visible and only the remaining 10% of the deteriorated pixels remain as burned-in.

  According to the correction target pixel extraction method 2 of the second embodiment, the human eye is inconspicuous and is not concerned. Further, for example, by not correcting 10% of the number of deteriorated pixels, it is possible to suppress an increase in current consumption accompanying the deterioration correction.

FIG. 9 is an operation flowchart of the correction coefficient calculation unit according to the second embodiment of the present invention.
FIG. 9A illustrates a correction coefficient calculation method 1 according to the second embodiment. This correction coefficient calculation method 1 is a method of calculating a correction coefficient that guarantees a luminance of 93% for a deteriorated pixel so that burn-in is not noticeable. The description will also be made with reference to the current VS luminance prediction characteristics (various characteristics are stored in the current VS luminance prediction characteristic storage unit 78) in FIG.

  The correction coefficient calculation unit 79 calculates a correction coefficient with a luminance of 93% for each correction target pixel stored in the correction target pixel storage unit 77 (step S31).

  Specifically, if one of the correction target pixels is recorded in the correction target pixel storage unit 77 as the light emission history T4, the current is I1 (correction coefficient 1.0) on the thick line T4 in FIG. Otherwise, the brightness will be 90% and the deterioration will be conspicuous. Therefore, by setting the correction coefficient U greater than 1.0, if a current obtained by multiplying I1 by the correction coefficient U is supplied to this pixel, light is emitted with a luminance of 93% and can be made inconspicuous.

  Assuming that one of the correction target pixels is the light emission history T5, if a current obtained by multiplying the correction coefficient X by I1 is passed through the thick line T5, the pixel emits light with a luminance of 93%, and may not be noticeable to human eyes. it can.

  These are calculated for all the pixels stored in the correction target pixel storage unit 77 and stored in the all pixel correction coefficient storage unit 80 (step S32), thereby guaranteeing a luminance of 93% of the correction target pixel. The all-pixel correction coefficient storage unit 80 stores pixels that are not correction targets as a correction coefficient 1.0 (step S32).

Conventionally, the luminance is guaranteed to 100% for the deteriorated pixels, that is, the correction coefficient W is set for the pixels of the light emission history T4 and the correction coefficient Z is set for the pixels of the light emission history T5.
On the other hand, according to the correction coefficient calculation method 1 of the second embodiment of the present invention, the correction coefficient is a luminance 93% guarantee, burn-in becomes inconspicuous, and an increase in current consumption for correction is suppressed compared to the conventional one. be able to.

  FIG. 9B illustrates a correction coefficient calculation method 2 according to the second embodiment. This correction coefficient calculation method 2 is a method of making the burn-in more inconspicuous by calculating a correction coefficient for ensuring that the luminance exceeds 93%, which is brighter than the luminance 93%, when there is a margin in the current consumption of the power source.

  The correction coefficient calculation unit 79 calculates a correction coefficient with a luminance n% guarantee for each correction target pixel stored in the correction target pixel storage unit 77. First, it starts from luminance n% = 93% (step S41). Next, the sum of the correction coefficient of luminance n% = 93% guaranteed for the correction target pixel and the correction coefficient (1.0) of other pixels that are not corrected is calculated, and the sum / total number of pixels = average value (all pixel correction) The coefficient average value is calculated (step S42).

  On the other hand, the current consumption of the organic EL display unit 90 is determined in advance by experiments or the like, for example, in specific video data and without luminance correction, that is, the current consumption having the same meaning as the average value of all pixel correction coefficients = 1.0. ing. Then, a power source having a predetermined capacity is prepared with reference to it. From the margin of the power source capacity and the like, for example, a power source allowable correction coefficient = 1.3 is determined in advance.

  The correction coefficient calculation unit 79 compares the average value of all pixel correction coefficients calculated in step S42 with a predetermined power supply allowable correction coefficient = 1.3 (step S43). If the average value of all pixel correction coefficients calculated with the luminance n% = 93% guarantee is smaller than the power supply allowable correction coefficient = 1.3, the luminance n% is increased to 94% guarantee and recalculated in steps S41 and S42.

  Specifically, the correction coefficient V is set for the pixels of the light emission history T4 (FIG. 5B), the correction coefficient Y is set for the pixels of the light emission history T5, and an average value of all pixel correction coefficients is obtained. Then, the comparison is made again (step S43), and the correction coefficient for each pixel at the average value of all the pixel correction coefficients that is the largest within a range not exceeding the power supply allowable correction coefficient = 1.3 is finally determined, and the all-pixel correction coefficient storage unit 80 (step S44).

  According to the correction coefficient calculation method 2 of the second embodiment of the present invention, when there is a margin in the current consumption of the power supply, the correction coefficient for guaranteeing a brightness exceeding 93% that is brighter than the brightness 93% is calculated, and burn-in is prevented. Further, it can be made inconspicuous.

  FIG. 10 is an operation flowchart of the correction coefficient calculation unit according to the second embodiment of the present invention, which is the correction coefficient calculation method 3 according to the second embodiment. This correction coefficient calculation method 3 is a correction method that makes burn-in less noticeable when there is no margin in the current consumption of the power supply and the average current for correction cannot be increased.

  For all pixels, the correction coefficient calculation unit 79 lowers the luminance of a pixel with a small light emission record (for example, T1) with a correction coefficient <1.0, and a pixel with a large light emission record (for example, T5) has a correction coefficient> 1.0. The brightness is increased and the correction coefficient is determined so that the brightness difference falls within 7% (step S51). Therefore, the light emission results of all the pixels including the pixels that have not deteriorated are recorded in the correction target pixel storage unit 77.

  Specifically, the pixel of the light emission history T1 (FIG. 5B) is reduced from the luminance 100% to the luminance 93% as the correction coefficient Q. For the pixel of the light emission history T5, the correction coefficient R is increased from luminance 87% to luminance 90%. As a result, the difference in brightness between the two is within 7%. In this way, the correction coefficients are determined for all the pixels so that the difference between the maximum luminance and the minimum luminance is within 7%.

  Next, the total sum and average value (all pixel correction coefficient average value) of the correction coefficients of all pixels are calculated (step S52). Then, the average value of all pixel correction coefficients is compared with the power supply allowable correction coefficient = 1.0 (step S53). If the two are different, the process returns to step S51, and the correction coefficient of each pixel is changed so that the average value of all pixel correction coefficients approaches 1.0.

  If the two match (may include substantially matching), the correction coefficient of each pixel at that time is finally determined and stored in the all-pixel correction coefficient storage section 80 (step S54), and the correction coefficient calculation section 79 is performed. Terminate the process.

  According to the correction coefficient calculation method 3 of the second embodiment of the present invention, when there is no margin in the power consumption current and the average current for correction cannot be increased, the luminance of the pixel with a small emission performance and no deterioration is obtained. The brightness of a pixel that has deteriorated due to a large light emission record can be increased, and burn-in can be made inconspicuous.

  Thereafter, whenever the organic EL display unit 90 is used, the multiplier 82 multiplies each pixel of the video data in the video storage unit 81 by the correction coefficient for each pixel in the all-pixel correction coefficient storage unit 80. The corrected video data is created and transmitted to the organic EL display unit 90.

  The video data in the video storage unit 81 is tone data including halftone, and the halftone data is also multiplied by a correction coefficient. For example, in the case of the correction coefficient calculation method 1 of Example 2 in FIG. 9A, when the correction coefficient U (luminance 93% guaranteed) is applied to the pixel of the light emission history T4 in FIG. The pixel emits light in accordance with the gradation within the range of the correction coefficient U or less with the point of the correction coefficient U as pure white video data on the thick line T4.

  When the correction coefficient U (luminance 93% guaranteed) is applied to the pixel of the light emission history T5, the light emission of this pixel is equal to or less than the correction coefficient X with the point of the correction coefficient X as pure white video data on the thick line T5. In the range of, light emission according to the gradation is performed.

  Since the pixels of the light emission history T1 are not corrected (correction coefficient 1.0), the correction coefficient 1.0 is obtained by setting the point (luminance 100%) of the correction coefficient 1.0 as pure white video data on the thick line T1. Light emission according to gradation is made in the following range.

  Since the pixels of the light emission history T2 are not corrected (correction coefficient 1.0), the correction coefficient 1.0 of the point of the correction coefficient 1.0 (luminance over 93%) on the thick line T2 is set as pure white video data. Light emission according to the gradation is made within a range of 0 or less.

  Since the pixel of the light emission history T3 is not corrected (correction coefficient 1.0), the correction coefficient 1.0 is obtained by setting the point (luminance 93%) of the correction coefficient 1.0 as pure white video data on the thick line T3. Light emission according to gradation is made in the following range.

  Even if the pixels of the light emission history T4 and T5 are not subject to correction as in the case of a single deteriorated pixel, the correction coefficient is 1.0 on the thick line T4 and the thick line T5, respectively (the luminance is 90%, 87%) is white image data, and light emission according to gradation is performed within a correction coefficient of 1.0 or less.

  The organic EL display unit 90 is capable of obtaining a dynamic current change in a range from the left side of the horizontal axis in FIG. This is a configuration having range characteristics.

  In the second embodiment, the trigger condition for performing the correction process is that there is a pixel that has deteriorated to a luminance of less than 93%. For example, the trigger condition is a time point at which the luminance has deteriorated to less than 95%. If there is a margin in current consumption, correction with luminance exceeding 95% may be performed.

Further, the correction processing (correction coefficient calculation method 1, 2, or 3) of the correction coefficient calculation unit 79 is performed on the correction target deteriorated pixel extracted by the correction target pixel extraction unit 76 (correction target pixel extraction method 1 or 2). However, for example, even if a correction process with 100% luminance, which has been conventionally performed, is performed on the deteriorated pixel to be corrected extracted by the correction target pixel extraction unit 76 (correction target pixel extraction method 1 or 2). Good. Even in this case, the current consumption can be suppressed as compared with the conventional case.
Further, the correction processing (correction coefficient calculation method 1, 2, or 3) of the correction coefficient calculation unit 79 may be performed for all the deteriorated pixels as correction target pixels. Even in this case, the current consumption can be suppressed as compared with the conventional case.

  In addition, the lifetime of the organic EL deteriorates as the current-time product increases as shown in the lifetime curve of FIG. 5, but as another factor, the lifetime also deteriorates as the temperature increases. A life curve including this temperature can be obtained in advance as experiments and manufacturer data. Then, a means for measuring the temperature of the organic EL may be provided, and the correction may be performed in consideration of the actual use temperature.

According to the second embodiment of the present invention, luminance can be corrected in consideration of current consumption.
Note that the display device 100 can be applied to a personal computer, a television, a mobile phone, and the like.

1 is a block diagram of a display device according to Embodiment 1 of the present invention. 1 is a block diagram of a column controller of a display device according to Embodiment 1 of the present invention. 1 is a block diagram of a row scanning control unit of a display device according to Embodiment 1 of the present invention. 1 is a circuit diagram of a display panel of a display device according to Embodiment 1 of the present invention. The figure explaining the brightness lifetime characteristic of organic EL which concerns on Example 2 of this invention. The figure explaining the display screen of the organic electroluminescent display part of the display apparatus which concerns on Example 2 of this invention. The block diagram of the display apparatus which concerns on Example 2 of this invention. 10 is an operation flowchart of a correction target pixel extraction unit according to the second embodiment of the present invention. The operation | movement flowchart of the correction coefficient calculation part which concerns on Example 2 of this invention. The operation | movement flowchart of the correction coefficient calculation part which concerns on Example 2 of this invention.

Explanation of symbols

21 Video storage unit 22 Measurement luminance storage unit 23 Initial luminance storage unit 24 Control unit 25 Video controller 30 Column control unit 31 Signal driver / receiver 32 Current supply driver 33 Video analog output 34 Timing control 35 A / D converter 36 3-state receiver 37 3-state driver 38 timing control 39 buffer 50 row scanning control unit 51 light receiving scanning driver 52 write / read scanning driver 53 timing control 54 buffer 55 timing control 56 buffer 60 display panel 70 control unit 71 light emission result calculation unit 72 all pixel light emission result Storage unit 73 Life prediction characteristic storage unit 74 Degraded pixel extraction unit 75 Deterioration pixel storage unit 76 Correction target pixel extraction unit 77 Correction target pixel storage unit 78 Current VS luminance prediction characteristic storage unit 79 Correction coefficient calculation unit 80 All pixel correction coefficient storage unit 81 Video memory 82 multiplier 90 organic EL display unit 100 display unit 200 display unit

Claims (9)

A display device having a display means in which a plurality of light emitting pixels are arranged and a control means for controlling the display means,
The control means includes
Prediction characteristics of the light emission luminance associated with the use history value of the light emitting pixel at a reference light emission current, and a second use history in which the use history value is reduced to a predetermined second light emission luminance compared to the initial first light emission luminance. Life characteristic storage means for storing values in advance;
A light emission result calculating means for calculating a use result value for displaying video data for each light emitting pixel of the display means and storing it in a light emission result storage means;
When it is determined that the use record value of the light emission record storage unit exceeds the second use history value and is a set pixel, the gradation of the portion corresponding to the set pixel is increased and the video data is displayed on the display unit. A display device comprising correction means for displaying on the display. The correction means includes
When it is determined that the use record value of the light emission record storage unit exceeds the second use history value, the gradation of pixels randomly extracted at a predetermined ratio among the light emitting pixels exceeding the second use history value The display device according to claim 1, wherein video data is displayed on the display unit at an increased degree. A display device having a display means in which a plurality of light emitting pixels are arranged and a control means for controlling the display means,
The control means includes
Prediction characteristics of the light emission luminance associated with the use history value of the light emitting pixel at a reference light emission current, and a second use history in which the use history value is reduced to a predetermined second light emission luminance compared to the initial first light emission luminance. Life characteristic storage means for storing values in advance;
Current vs. luminance characteristic storage means for preliminarily storing prediction characteristics of light emission luminance when the light emission current is changed for each of a plurality of use history values of the light emitting pixels;
A light emission result calculating means for calculating a use result value for displaying video data for each light emitting pixel of the display means and storing it in a light emission result storage means;
A deteriorated pixel extracting means for extracting a pixel having a use record value of the light emission record storage means exceeding the second use history value and storing it in the deteriorated pixel storage means;
Correction target pixel extraction means for storing a part or all of the deteriorated pixels stored in the deteriorated pixel storage means as correction target pixels in the correction target pixel storage means;
Correction of the reference light emission current ratio is performed using a current value that guarantees the predetermined second light emission luminance based on a prediction characteristic of a use history value of the current versus luminance characteristic storage unit corresponding to the actual use value for each correction target pixel. Correction coefficient calculating means for calculating the coefficient and storing it in the correction coefficient storage means;
A display device comprising correction means for creating corrected video data obtained by multiplying the video data by the correction coefficient for each correction target pixel and displaying the corrected video data on the display means. Furthermore, it comprises a power supply allowable correction coefficient storage means for storing in advance an average value of the correction coefficients corresponding to the power supply power consumption allowable value for the correction as a power supply allowable correction coefficient,
The correction coefficient calculation means includes
A current value that guarantees a light emission luminance exceeding the predetermined second light emission luminance based on a prediction characteristic of a use history value of the current vs. luminance characteristic storage unit corresponding to a use result value for each correction target pixel is the reference light emission. Calculated as the current ratio correction coefficient, calculates the sum and average of the correction coefficients of all pixels, compares the average value with the power supply allowable correction coefficient, and has the highest emission luminance within the range not exceeding the power supply allowable correction coefficient 4. The display device according to claim 3, wherein the correction coefficient storage means stores the correction coefficient of each pixel that guarantees the above. Furthermore, it comprises power supply allowable correction coefficient storage means for preliminarily storing the average value of the correction coefficients corresponding to the power supply power consumption allowable value for correction as a power supply allowable correction coefficient 1.0,
The correction coefficient calculation means includes
For all the pixels, based on the prediction characteristics of the usage history value of the current vs. luminance characteristic storage means corresponding to the actual usage value, the pixel having a small usage history value is used as a correction coefficient for the reference light emission current ratio. A correction coefficient is larger than 1.0 for a pixel having a smaller use history value than a pixel having a smaller use history value than 1.0, and the luminance difference between the pixel having the smaller use history value and the pixel having a larger use history value is within a predetermined range. The correction coefficient is set, the sum and average value of the correction coefficients of all the pixels are calculated, and the correction coefficient of each pixel whose average value is substantially the same as the power supply allowable correction coefficient 1.0 is stored in the correction coefficient storage means. The display device according to claim 3.   5. The display device according to claim 3, wherein the predetermined second light emission luminance is a light emission luminance of 93% or more compared to the initial first light emission luminance. A pixel panel is arranged at each coordinate position of a matrix intersection of a plurality of columns and a plurality of rows, and each pixel unit is controlled by a signal on a control line wired in the matrix,
Each pixel portion is
A light-emitting element, a light-receiving element that receives light emitted from the light-emitting element and sends a light-receiving signal to a pixel portion at a first diagonally adjacent coordinate position adjacent to the pixel portion in one diagonal direction, opposite to the one diagonal direction of the pixel portion A receiving unit that receives a light reception signal transmitted from the light receiving element of the pixel unit at the second obliquely adjacent coordinate position adjacent in the direction;
The control line is
A first column control line and a second column control line in each column;
Each row has a first row control line and a second row control line;
The coordinates of the intersection of the column and the row by the signals of the first column control line, the second column control line, the first row control line, and the second row control line of each arbitrary column and row The light emitting element of the pixel portion at the position emits light, the light emission is received by the light receiving element of the pixel portion, and a light reception signal is sent to the pixel portion at the first diagonally adjacent coordinate position,
A first column control line, a second column control line, a first row control line, and a second column and row respectively corresponding to the coordinates of the pixel portion at the first obliquely adjacent coordinate position with respect to the light emitting pixel portion that emits light. A display panel, wherein a light reception signal of a light receiving element of the light emitting pixel unit is read for light emission correction of the light emitting element of the light emitting pixel unit by a signal of the row control line. A pixel panel is arranged at each coordinate position of a matrix intersection of a plurality of columns and a plurality of rows, and each pixel unit is controlled by a signal on a control line wired in the matrix,
Each pixel portion is
A light emitting element, a capacitor, a first transistor for writing a video signal to the capacitor, a second transistor for passing a current to the light emitting element, a first transistor that receives light emitted from the light emitting element and is adjacent to the pixel portion in one oblique direction A light receiving element that transmits a light receiving signal to a pixel portion at an obliquely adjacent coordinate position, and a light receiving signal that is transmitted from a light receiving element at a pixel portion at a second obliquely adjacent coordinate position that is adjacent to the pixel portion in a direction opposite to the one oblique direction. A third transistor that
The control line is
A first column control line and a second column control line in each column;
Each row has a first row control line and a second row control line;
The coordinates of the intersection of the column and the row by the signals of the first column control line, the second column control line, the first row control line, and the second row control line of each arbitrary column and row A video signal is charged to the capacitor via the first transistor of the pixel portion at the position, and a current corresponding to the charge amount flows to the light emitting element via the second transistor, and the light emitting element emits light, and the light emission Is received by the light receiving element of the pixel portion and a light reception signal is sent to the pixel portion at the first obliquely adjacent coordinate position,
A first column control line, a second column control line, a first row control line, and a second column and row respectively corresponding to the coordinates of the pixel portion at the first obliquely adjacent coordinate position with respect to the light emitting pixel portion that emits light. The light receiving signal of the light receiving element of the light emitting pixel unit is transmitted through the third transistor and the first transistor of the pixel unit at the first obliquely adjacent coordinate position by the signal of the row control line A display panel which is read for light emission correction.   Among each of the pixel portions, the plurality of pixel portions at one end of the oblique one direction and the plurality of pixel portions at one end of the oblique one direction do not emit light or emit light to emit the light from the light emitting element. The display panel according to claim 7, wherein the display panel is a pixel not subjected to correction.

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