Tohoku Pioneer Corporation

Shinobu Adachi

Takayoshi Yoshida

Mayumi Ozaki

Light-emitting elements disposed on a light-emitting display panel are driven by constant currents, and the forward direction voltages of the light-emitting elements are obtained by a sampling/holding circuit. Then, the voltage output from a drive voltage source composed of a DC-DC converter is controlled by the forward direction voltages obtained by the sampling/holding circuit. For example, in a case in which the light emission luminance of the light-emitting display panel is changed or in other case, a sampling and holding operation is executed by the sampling/holding circuit in response to a control signal from a sampling timing control circuit at intervals shorter than ordinary intervals. With this arrangement, when light emission luminance of a light-emitting display panel is changed, the gentle changing characteristics of the light emission luminance thereof can be improved.

Drive method of light-emitting display panel and organic EL display device

In the upper half and a lower half of a display area, scanning is implemented such that the directions of scan selection operations are different from each other. The upper half of the panel is scanned from the upper end to the center of the screen, and at the same time the lower half of the panel is scanned from the lower end to the center of the screen. Control is performed such that the difference between the start time of the scan selection operation of the upper half of display area and the start time of the scan selection operation of the lower half of the display area is scanning time of at least one or more scan lines. The configuration avoids a problem that a bright line is generated momentarily on the boundary line of the upper half and the lower half of the panel can be avoided.

Self light emitting display panel and drive control method therefor

After a command signal corresponding to a gradation whose light emission is controlled is outputted from a controller IC, based on this, a combination of respectively different intensity conversion data are extracted from a linear data tableand a &#x3b3; correction data table. The respective intensity conversion data are analog converted by a first DACand a second DAC, and these are converted into a voltage level of a mean value by resistors R, Rand an addition circuit. By this voltage level of the mean value, an absorption current in a current mirror circuitis controlled, and as a result, a drive current accompanied by &#x3b3; correction for the light emitting elements can be obtained by the current mirror circuit. The first DACand the second DAChandle relatively simple intensity conversion data obtained from the linear data tableand the &#x3b3; correction data tableand analog convert such data. Therefore, a light emission control circuit accompanied by &#x3b3; correction can be realized without enlarging the circuit scale.

Growing community of inventors

Yonezawa, Japan

Shinobu Adachi