JP5631130B2 - Organic EL display device - Google Patents

Description

  In the present invention, for example, a plurality of organic EL (Electro-Luminescence) elements composed of a plurality of pixels are arranged in a matrix to form an organic EL module, and a plurality of organic EL modules are arranged in a matrix. The present invention relates to an organic EL display device constituting an organic EL display panel, and more particularly to an organic EL display device for improving the lifetime of the device.

  Conventionally, as an organic EL display device, as shown in Patent Document 1 (Japanese Patent No. 4225774), when selecting a gradation from arbitrary gradation data corresponding to display data and performing multi-gradation display, The upper bits of the gradation data are expressed by the gradation method using current amplitude modulation, the lower bits of the gradation data are expressed by the frame rate control gradation method, and the frame rate control gradation method is expressed by the current amplitude modulation. There is a gradation method added to the gradation method.

  As an organic EL display device, as shown in Patent Document 2 (Japanese Patent Laid-Open No. 2000-56727), a signal driver has a gradation display by a plurality of values of current or voltage output control, and a plurality of output time widths. There are some which can perform gradation display without requiring high speed operation and high accuracy by simultaneously performing gradation display by control.

  As an organic EL display device, as shown in Patent Document 3 (Japanese Patent Laid-Open No. 2001-109421), gradation is expressed by output amplitude value control when the luminance is low, and output time width control is performed when the luminance is high. There are some that realize gradation with high accuracy by expressing gradation by switching.

  Moreover, as an organic EL display device, there are those shown in FIGS. FIG. 10 is a block diagram showing a conventional organic EL display device. FIG. 11 is a waveform diagram showing a gradation control pattern of a conventional organic EL display device. FIG. 12 is a pattern diagram showing a pixel arrangement pattern of a conventional organic EL display device. FIG. 13 is a waveform diagram showing a gradation control pattern in a conventional organic EL display device.

  In the conventional organic EL display device, a plurality of organic EL elements 9 composed of a plurality of pixels 8 are arranged in a matrix to form an organic EL display panel 10, which is disposed on the organic EL display panel 10 and the substrate 11. The organic EL module 15 is configured by the control circuit 12, the image memory 13, and the drive circuit 14 that control the organic EL display panel 10. An organic EL display panel 7 is configured by arranging a plurality of organic EL modules 15 in a matrix.

  Each organic EL module 15 of the organic EL display panel 7 is connected through a BUS 17 via a buffer memory 16.

  Each organic EL module 15 displays an image divided according to the size of the module, and one image is displayed on the entire screen. In some cases, the organic EL module 15 includes a plurality of organic EL elements 9 arranged in a matrix to form the organic EL display panel 10 as necessary, and may include a power source.

  In the conventional organic EL display device, each organic EL element 9 or each organic EL module 15 is arranged so that the joint (joint) between each organic EL element 9 or each organic EL module 15 is not conspicuous in a tile shape (jointless). Placed close together. As the organic EL element 9, the organic EL element 9 applying the principle of CRT or discharge tube was used in the early days, but recently, it has been used for LED (Light Emitting Diode), outdoor ultra-high brightness, lightweight, It has been developed as a public display device that can be used for various purposes such as thin building wall surfaces. Various display devices such as LCDs (Liquid Crystal Displays), PDPs (Plasma Display Panels), and organic ELs are also suitable for performance and jointless layout, such as brightness and life, for large display applications. Can be applied to a large display device. The control of each display device is generally PWM (Pulse Width Modulation) control, in which a drive pulse with a constant peak value is applied to each pixel, and the cumulative time width of the drive pulse is proportional to the shade of the image. .

  In addition, when changing the luminance of the organic EL element 9, the luminance is controlled by making the current value constant and changing the lighting time to express gradation. That is, as shown in FIG. 11, the image signal has a period called 1 field 20. For example, the period called 1 field 20 is 1/60 seconds in 60H, which is the standard of Japanese television signals. When the brightness is brightest, the drive pulse width is lit for the maximum period, and when the brightness is darkest, it is not lit. By controlling the time width of the drive pulse, the lightness / darkness is expressed. This is called gradation control.

  Each unit of 20 fields is a control range, the maximum gradation allowable light emission time width as a display system is TA, and the light emission time width of the maximum gradation is TB1. The peak current value is ip.

  In general, the light emission time width of the drive pulse is completely digital, and it is possible to express gradation with high certainty. On the other hand, the height direction of the drive pulse is a current value and has an analog element, which is not used much.

  Incidentally, as shown in FIG. 12, among the plurality of pixels 8 within the control range, for example, the gradation of the pixel a, the pixel b, and the pixel c has a peak current value ip in the height direction as shown in FIG. Are constant, but the time width of the pulse, that is, the light emission time width of each gradation is d1, d2, and d3, which are different from each other, and the gradation corresponding to each pixel a, b, and c is expressed. . In the control range of one field 20, the maximum gradation allowable light emission time width is TA, and the light emission time width at the maximum gradation in the control range is TB1. The peak current value ip is the same for the pixels a, b, c, and the other pixels 8.

  Further, as shown in FIG. 13, in the display PWM control, TA is the maximum gradation allowable light emission time width of the pixel corresponding to the maximum luminance display. Each organic EL module 15 has means for detecting the maximum gradation of the pixels within the range for each control range of the organic EL module 15, and the light emission time width at the maximum gradation of the pixels detected here is TB1. And TA is a constant value, but TB1 varies depending on the image, and both have a relationship of TA ≧ TB1.

Japanese Patent No. 4225774 JP 2000-56727 A JP 2001-109421 A

  In the conventional organic EL display device described above, a driving pulse having a constant peak value, that is, a peak current value is generally applied to each pixel 8, and each pixel 8 of each organic EL element 9 in one field 20 that is a fixed time. The cumulative time width of the drive pulse applied to each is controlled so as to be proportional to the density of the image. The drive pulse width corresponding to the image data is short at low luminance and long at high luminance, but the same current flows in the peak current value ip of the drive pulse. That is, the peak current value ip of the drive pulse is the same at the maximum gradation and at the minimum gradation.

  That is, as shown in FIG. 13, the gradation of the pixel a is a state in which the light emission time width is d1 with respect to TA of the maximum gradation allowable light emission time width, and is approximately half lit, and the pixel b The light emission time width is d2 with respect to the maximum gradation allowable light emission time width TA, the light emission time width of the pixel a is smaller than d1, and the gray level of the pixel b is less than the gray level of the pixel a. It is a period. Further, the gradation of the pixel c has a light emission time width of d3 with respect to TA of the maximum gradation allowable light emission time width, the light emission time width of the pixel b is smaller than d2, and the gradation of the pixel c is the gradation of the pixel b. The lighting period is even shorter than the gradation.

  However, as a display system, it is possible to light up to the maximum gradation allowable light emission time width TA, but actually, the light emission time widths d1, d2, d3 of each gradation and the light emission time at the maximum gradation. The width is in a state of lighting only up to TB1. Therefore, the difference between the maximum gradation allowable light emission time width TA and the light emission time width at the maximum gradation with TB1 is useless, and there is a problem that the efficiency is inferior.

  In particular, a plurality of organic EL elements 9 composed of a plurality of pixels 8 are arranged in a matrix to form an organic EL display panel 10. The organic EL display panel 10 and the substrate 11 are disposed on the organic EL display panel 10. The organic EL module 15 is configured by the control circuit 12, the image memory 13, and the drive circuit 14 for controlling the organic EL display panel, and the organic EL display panel 7 is configured by arranging a plurality of the organic EL modules 15 in a matrix. In general, a display device for the public is often used at a high brightness in a bright environment, and the peak current value ip is a constant control in the control of image shading. The current value ip increases and the load on the organic EL element 9 increases. Therefore, there exists a subject that the lifetime of the organic EL element 9 becomes short.

  The present invention has been made in order to solve the above-described problems. In controlling the density of an image, an organic EL can be obtained by improving the efficiency of the light emission time width of the gradation and reducing the peak current value. An object of the present invention is to provide an organic EL display device capable of reducing the load on the element and extending the life of the organic EL element.

An organic EL display device according to the present invention includes an organic EL module configured by arranging a plurality of organic EL elements composed of a plurality of pixels in a matrix, and an organic EL display including a plurality of the organic EL modules arranged in a matrix. panel constitute, an organic EL display device which is gradation controlled by the PWM control Te top Daikaicho allowable emission time width in odor one field, the maximum gradation of the light emitting time width and peak value in the organic EL module maximum gradation detector circuit, the maximum gradation the emission time width of the top Daikaicho data detected by the detecting circuit is inputted, prior Symbol onset light for detecting the maximum gradation data of the peak current value is time based on the width, the emission time width, and a data conversion circuit for performing conversion processing multiplied by the coefficient of the maximum gradation allowable emission time width / the emission time width, the maximum gradation Is the peak current value of the maximum tone data detected by the circuit out input, based on the prior Kipi over leak current value, the luminance value the peak current value is substantially the same as the luminance before data conversion process Thus, a current value conversion circuit that performs current value conversion processing is provided.

  According to the organic EL display device according to the present invention, an organic EL display device capable of extending the life of the device can be obtained.

It is a block diagram which shows the organic electroluminescence display concerning Embodiment 1 of this invention. It is a block diagram which shows 1 module in the organic electroluminescence display concerning Embodiment 1 of this invention. It is a block diagram which shows the relationship between the data signal driver and scanning signal driver in the organic electroluminescent display apparatus concerning Embodiment 1 of this invention. FIG. 5 is a waveform diagram showing output states of a data signal driver and a scanning signal driver in the organic EL display device according to Embodiment 1 of the present invention. FIG. 4 is a waveform diagram showing a gradation control pattern in the organic EL display device according to Embodiment 1 of the present invention.

It is a block diagram which shows the organic electroluminescence display panel in the organic electroluminescence display which concerns on Embodiment 2 of this invention. It is a block diagram which shows the organic electroluminescence display which concerns on Embodiment 2 of this invention. It is a block diagram which shows the organic electroluminescence display which concerns on Embodiment 3 of this invention. It is a block diagram which shows the organic electroluminescence display which concerns on Embodiment 4 of this invention.

It is a block diagram which shows the conventional organic EL display apparatus. It is a wave form diagram which shows the gradation control pattern of the conventional organic EL display apparatus. It is a pattern diagram which shows the pixel arrangement pattern of the conventional organic EL display apparatus. It is a wave form diagram which shows the gradation control pattern in the conventional organic EL display apparatus.

Embodiment 1 FIG.
Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 5. In these drawings, the same or equivalent members and parts will be described with the same reference numerals. 1 is a block diagram showing an organic EL display device according to Embodiment 1 of the present invention. FIG. 2 is a block diagram showing one module in the organic EL display device according to Embodiment 1 of the present invention. FIG. 3 is a block diagram showing the relationship between the data signal driver and the scanning signal driver in the organic EL display device according to Embodiment 1 of the present invention. FIG. 4 is a waveform diagram showing output states of the data signal driver and the scanning signal driver in the organic EL display device according to Embodiment 1 of the present invention. FIG. 5 is a waveform diagram showing a gradation control pattern in the organic EL display device according to Embodiment 1 of the present invention.

  In these figures, 1 is a video system, 2 is a computer system, 3 is a display controller 3, a TV signal processing unit 4 input from the video system 1, a graphic processing unit 5 input from the computer system 2, and character information. And a processing unit 6.

  Reference numeral 107 denotes an organic EL display panel. A plurality of organic EL elements 9 composed of a plurality of pixels 8 are arranged in a matrix to form an organic EL display panel 110. The organic EL display panel 110, a control circuit 112 disposed on a substrate 111, and an image memory 113 are arranged. The organic EL module 115 is configured by the drive circuit 114. An organic EL display panel 107 is configured by arranging a plurality of organic EL modules 115 in a matrix.

  Each organic EL module 115 of the organic EL display panel 107 is connected through the BUS 17 via the buffer memory 16.

  FIG. 2 shows one organic EL module 115, and the drive circuit 114 includes a data signal driver 118 and a scanning signal driver 119, and is driven by the control circuit 112.

  As shown in FIG. 3, the data signal driver 118 outputs signals d1, d2, d3, and dn, and the scanning signal driver 119 outputs signals S1, S2, S3, and Sn. The organic EL element 9 is connected to the intersection of the signal line from the data signal driver 118 and the signal line from the scanning signal driver 119 so as to connect the signal line from the data signal driver 118 and the signal line from the scanning signal driver 119. .

  FIG. 4 shows output states of the data signal driver 118 and the scanning signal driver 119. When the signal line S1 is output from the scanning signal driver 119 and turned on, the data signal driver 118 and the scanning signal driver 119 output the signal line S1. The organic EL element 9 connected to the signal lines d1, d2, d3, dn is driven. At this time, since the signal lines S2, S3, and Sn of the scanning signal driver 119 are not output, the signal lines d1, d2, and d2 from the data signal driver 118 that intersect the signal lines S2, S3, and Sn of the scanning signal driver 119 are output. The organic EL element 9 connected to d3 and dn is not driven.

  When the signal line S2 is output from the scanning signal driver 119 and turned on, the organic EL element 9 connected to the signal lines d1, d2, d3, and dn from the data signal driver 118 intersecting the signal line S2 is driven. It has become so. At this time, since the signal lines S1, S3, and Sn of the scanning signal driver 119 are not output, the signal lines d1, d2, and d2 from the data signal driver 118 that intersect with the signal lines S1, S3, and Sn of the scanning signal driver 119 are output. The organic EL element 9 connected to d3 and dn is not driven.

  When the signal line S3 is output from the scanning signal driver 119 and turned on, the organic EL element 9 connected to the signal lines d1, d2, d3, and dn from the data signal driver 118 intersecting the signal line S3 is driven. It has become so. At this time, since the signal lines S1, S2, and Sn of the scanning signal driver 119 are not output, the signal lines d1, d2, and d2 from the data signal driver 118 that intersect the signal lines S1, S2, and Sn of the scanning signal driver 119 are output. The organic EL element 9 connected to d3 and dn is not driven.

  When the signal line Sn is output from the scanning signal driver 119 and turned on, the organic EL element 9 connected to the signal lines d1, d2, d3, dn from the data signal driver 118 intersecting the signal line Sn is driven. It has become so. At this time, since the signal lines S1, S2, and S3 of the scanning signal driver 119 are not output, the signal lines d1, d2, and d2 from the data signal driver 118 that intersect with the signal lines S1, S2, and S3 of the scanning signal driver 119 are output. The organic EL element 9 connected to d3 and dn is not driven.

  As described above, the output from the scanning signal driver 119 is output in the order of the signal lines S1, S2, S3, and Sn, and is further repeated at high speed in the order of the signal lines S1, S2, S3, and Sn. Seems to be displayed continuously.

  By the way, the luminance of each pixel is substantially proportional to the product of the peak current value of the drive pulse and the time width. In particular, in a display device such as an organic EL in which the current density of the light emitting part affects the lifetime, a method of reducing the current density by reducing the peak current value and increasing the light emission time width to obtain the same luminance is effective.

  In the first embodiment, a case where the organic EL display panel 110 is targeted as a control range is shown. As shown in FIG. 2, a maximum gradation detection circuit 121 is mounted on the organic EL module 115, and the organic EL display is mounted. The maximum gradation in the display panel 110 is detected by the maximum gradation detection circuit 121. The data of the maximum gradation detected by the maximum gradation detection circuit 121 is transmitted to the data conversion circuit 122. In the data conversion circuit 122, based on the light emission time width TB1 of the maximum gradation detected by the maximum gradation detection circuit 121, data conversion processing is performed by multiplying the light emission time width TB1 by a coefficient of TA / TB1. The maximum gradation data detected by the maximum gradation detection circuit 121 is transmitted to the current value conversion circuit 123. In the current value conversion circuit 123, the peak value is set so that the luminance value is substantially the same as the luminance before the data conversion process based on the peak current value ip which is the peak value of the maximum gradation detected by the maximum gradation detection circuit 121. A conversion process for reducing the current value is performed on the current value ip. As an example of the conversion process, the current value conversion circuit 123 performs a current value conversion process by multiplying by a coefficient of TB1 / TA when the relationship between current and luminance is a direct proportional relationship.

  The data converted by the data conversion circuit 122 and the data converted by the current value conversion circuit 123 are output to the data signal driver 118, respectively. Based on the converted data, Gradation control is performed.

  That is, the light emission time width TB1 of the maximum gradation is turned on to the maximum gradation allowable light emission time width TA by multiplying the light emission time width TB1 by the coefficient of TA / TB1. However, since it is not possible to change the brightness, simply extending the light emission duration for a long time will make it too bright and the brightness will change. The current is reduced to the same brightness so that the brightness is the same. Thus, the peak current value is lowered without changing the luminance by multiplying the peak current value ip of the maximum gradation by the coefficient of TB1 / TA.

  As shown in FIG. 5, if the light emission time width TB1 of the maximum gradation is multiplied by the coefficient of TA / TB1, the light emission time width becomes TB11, and TB11 = TA, so that the maximum gradation allowable light emission time width TA is reached. Can be lit. Therefore, there is no difference between the maximum gradation allowable light emission time width TA and the light emission time width at the maximum gradation with the TB11, and there is no useless state as in the conventional device described above, and the efficiency is remarkably improved. Further, since the peak current value ip of the maximum gradation is multiplied by the coefficient TB1 / TA, the peak current value iq is smaller than the peak current value ip. When the peak current value iq is smaller than the peak current value ip, the load on the organic EL element 9 can be reduced, and the life of the organic EL element 9 can be extended. If it is strong, the lifetime of the organic EL display device as a whole can be extended.

  Further, the pixel a, the pixel b, the pixel c, and the other pixel 8 are multiplied by the coefficient of TA / TB1 at the maximum gradation and the coefficient of TB1 / TA at the maximum gradation. As shown in FIG. 5, the light emission time width of the pixel a can be extended longer than d1 by d11, and the peak current value of the pixel a can be made smaller than the peak current value ip by ia. The light emission time width of the pixel b can be extended longer than d2 by d12, and the peak current value of the pixel b can be made smaller than the peak current value ip by ib. The light emission time width of the pixel c can be extended longer than d3 by d13, and the peak current value of the pixel c can be made smaller than the peak current value ip by ic.

Embodiment 2. FIG.
A second embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a block diagram showing an organic EL display panel in an organic EL display device according to Embodiment 2 of the present invention. FIG. 7 is a block diagram showing an organic EL display device according to Embodiment 2 of the present invention.

  In the above-described first embodiment, the case where the organic EL display panel 10 is controlled is described by arranging a plurality of organic EL elements 9 that are mounted on the organic EL module 115 and configured by a plurality of pixels 8 in a matrix. However, in the second embodiment of the present invention, each organic EL element 9 is controlled.

  Each organic EL element 9 is integrated and controlled by an FPGA (Field Programmable Gate Array) 124 equipped with a maximum gradation detection circuit 121, a data conversion circuit 122, a current value conversion circuit 123, and the like.

  In the video data for each field 20, the maximum gradation of the pixels in the control range is collected for each control range of the organic EL element 9. When the collected light emission time width of the maximum gradation is smaller than the maximum gradation allowable light emission time width TA that can be expressed by the display system, the lighting period of all the elements within the control range of the organic EL element 9 is lengthened. . As in the first embodiment described above, the long extension coefficient is determined from the maximum gradation light emission time width within the control range of one organic EL element 9 and the maximum gradation allowable light emission time width TA that can be expressed by the display system. Be indexed.

  That is, when TC is the light emission time width of the maximum gradation within the control range of one organic EL element 9, the coefficient for multiplying the light emission time width of the maximum gradation by TC is TA / TC, and the peak value of the maximum gradation is The coefficient by which the peak current value ip is is TC / TA.

  By performing gradation control for each organic EL element 9 by using an FPGA (Field Programmable Gate Array) 124, the above-described gradation control is performed compared to the gradation control for the organic EL display panel 110 of the organic EL module 115. An organic EL display device that is more efficient than Embodiment 1 can be obtained.

  Further, even when the maximum gradation of each organic EL element 9 is different or partially has the same light emission time width of the same gradation, fine gradation control can be performed.

Embodiment 3 FIG.
The third embodiment will be described with reference to FIG. FIG. 8 is a block diagram showing an organic EL display device according to Embodiment 3 of the present invention.

  The gradation control target of the first embodiment described above is the organic EL display panel 110 of the organic EL module 115, and the gradation control target of the second embodiment described above is each organic EL element 9 of the organic EL display panel 110. However, in the third embodiment, the organic EL display panel 107 in which a plurality of organic EL modules 115 are arranged in a matrix is the target for gradation control.

  The entire organic EL display panel 107 is set as a control range, and the maximum gradation in the entire organic EL display panel 107 is detected by the maximum gradation detection circuit 121 of the control circuit 125. The data of the maximum gradation detected by the maximum gradation detection circuit 121 is transmitted to the data conversion circuit 122. In the data conversion circuit 122, based on the light emission time width of the maximum gradation detected by the maximum gradation detection circuit 121, when the light emission time width is TD, the light emission time width TD is multiplied by a coefficient of TA / TD. Data conversion processing is performed. The maximum gradation data detected by the maximum gradation detection circuit 121 is transmitted to the current value conversion circuit 123. In the current value conversion circuit 123, based on the peak current value ip which is the peak value of the maximum gradation detected by the maximum gradation detection circuit 121, a current value conversion process in which the peak current value ip is multiplied by a coefficient of TD / TA. Is done.

  The data converted by the data conversion circuit 122 and the data converted by the current value conversion circuit 123 are output to the data signal driver 118, respectively. Based on the converted data, Gradation control is performed.

  According to the third embodiment, since the entire organic EL display panel 107 is in the control range, the control configuration can be simplified.

Embodiment 4 FIG.
The fourth embodiment will be described with reference to FIG. FIG. 9 is a block diagram showing an organic EL display device according to Embodiment 4 of the present invention.

  In the fourth embodiment, the dimming data signal 126 capable of controlling the brightness can be transmitted in common to the organic EL modules 115 of the organic EL display panel 107.

  According to the fourth embodiment, only the dimming data signal 126 is uniformly transmitted for each organic EL module 115, and each organic EL module 115 or each organic EL element 9 is based on the dimming data signal 126. Current value conversion is performed in the current value conversion circuit 123, and brightness density control is performed.

  The dimming data signal 126 is uniformly transmitted for each organic EL module 115 for each organic EL module 115. If the dimming data value of the dimming data signal 126 is 0.5, for example, the brightness of the entire organic EL display panel 107 is uniformly reduced to half, and the dimming data value of the dimming data signal 126 is 0.1, for example. If so, the brightness of the entire organic EL display panel 107 is uniformly reduced to 1/10. If the dimming data value of the dimming data signal 126 is 1, for example, the luminance of the entire organic EL display panel 107 does not change, and if the dimming data value of the dimming data signal 126 is 1.0, for example, the organic EL The brightness of the entire display panel 107 is uniformly increased by 10%. Thus, the brightness of the entire organic EL display panel 107 can be uniformly controlled.

  According to the present invention, it is possible to reduce the load on the organic EL element by increasing the efficiency of the light emission time width of the gradation and reducing the peak current value, thereby extending the life of the organic EL element. It is suitable for realizing an organic EL display device.

8 pixels 9 organic EL elements 107 organic EL display panel 110 organic EL display panel 115 organic EL module 121 maximum gradation detection circuit 122 data conversion circuit 123 current value conversion circuit 126 dimming data signal TA maximum gradation allowable light emission time width TB1 maximum Light emission time width of gradation TB11 Light emission time width of maximum gradation ip peak current value iq peak current value

Claims (5)

The organic EL device composed of a plurality of pixels constituting the organic EL module by a plurality arranged in a matrix, wherein the organic EL module by a plurality arranged in a matrix form to constitute the organic EL display panel, the maximum of one field an organic EL display device which is gradation controlled by the PWM control Te gradation allowable emission time width in odor, the maximum gradation data of the peak current value which is the maximum gradation emission time width and pulse height in the organic EL module a maximum gradation detector circuit for detecting the maximum gradation the emission time width of the top Daikaicho data detected by the detecting circuit is inputted, based on the prior SL luminous time width, the emission time width the maximum data conversion circuit for performing tone allowable emission time width / the emission time conversion process multiplied by a factor of width, the maximum tone which is detected by the maximum gradation detector circuit Is inputted the peak current value over data, before based on Kipi over leak current value, the luminance value the peak current value is a current value to perform the current conversion process to be approximately the same as the luminance before data conversion process An organic EL display device comprising a conversion circuit. The organic EL device composed of a plurality of pixels constituting the organic EL module by a plurality arranged in a matrix, wherein the organic EL module by a plurality arranged in a matrix form to constitute the organic EL display panel, the maximum of one field an organic EL display device which is gradation controlled by the PWM control Te gradation allowable emission time width in odor, the maximum gray level data of the peak current value which is a light-emitting time width and peak value of the maximum gradation in the organic EL device a maximum gradation detector circuit for detecting the maximum gradation the emission time width of the top Daikaicho data detected by the detecting circuit is inputted, based on the prior SL luminous time width, the emission time width the maximum gradation allowable data conversion circuit for performing conversion processing multiplied by the coefficient of emission time width / the emission time width, the maximum gradation data detected by the maximum gradation detector circuit The peak current value is inputted, based on prior Kipi over leak current value, the luminance value the peak current value and the current value conversion circuit for performing current conversion to be approximately the same as the luminance before data conversion process An organic EL display device comprising: The organic EL device composed of a plurality of pixels constituting the organic EL module by a plurality arranged in a matrix, wherein the organic EL module by a plurality arranged in a matrix form to constitute the organic EL display panel, the maximum of one field an organic EL display device which is gradation controlled by the PWM control Te gradation allowable emission time width in odor, the maximum gray-scale level of the peak current value which is a light-emitting time width and peak value of the maximum gradation in the organic EL display panel a maximum gradation detector circuit for detecting data, the maximum gradation is detected by the detection circuit and the light emitting time width of the top Daikaicho data is input, based on the prior SL luminous time width, the emission time width to the maximum gradation allowable emission time and the data conversion circuit for performing a width / the emission time conversion process multiplied by a factor of width, said detected by the maximum gradation detector circuit Daikaicho the peak current value of the data is input, based on the prior Kipi over leak current value, the current value conversion processing so as to be substantially the same luminance value the peak current value and luminance before data conversion process An organic EL display device comprising a current value conversion circuit for performing the operation.   4. The current value conversion circuit according to claim 1, wherein the current value conversion circuit is a current value conversion process obtained by multiplying the peak current value by a coefficient of the light emission time width / the maximum gradation allowable light emission time width. The organic EL display device according to any one of the above.   The dimming data signal for controlling the luminance is uniformly transmitted to the current value conversion circuit to uniformly control the luminance of the entire organic EL display panel. 2. The organic EL display device according to item 1.

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