公开(公告)号：US09824631B2

公开(公告)日：2017-11-21

申请号：US14819594

申请日：2015-08-06

Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.

Inventor： Shunpei Yamazaki ,  Hajime Kimura ,  Atsushi Umezaki ,  Yasunori Yoshida ,  Hideaki Shishido ,  Takuya Kimishima ,  Yasuyuki Arai

IPC: G09G3/3233 ,  G09G3/00 ,  G09G3/20 ,  G09G3/3225

CPC classification number: G09G3/3233 ,  G09G3/006 ,  G09G3/20 ,  G09G3/2022 ,  G09G3/3225 ,  G09G2300/0809 ,  G09G2300/0819 ,  G09G2300/0842 ,  G09G2310/0272 ,  G09G2310/0275 ,  G09G2320/0233 ,  G09G2320/0295 ,  G09G2320/046 ,  G09G2320/048 ,  G09G2330/022 ,  G09G2340/145

Abstract: In a display element such as an organic EL element, deterioration progresses due to light emission, and emission luminance is lowered even if the same voltage is applied to the display element. Therefore, use over time causes variations in luminance of each pixel, thereby a so-called “image burn-in” phenomenon occurs. Given this factor, the invention provides a display device which can reduce the difference in deterioration of a display element in each pixel and suppress variations in light emission of a display element in a pixel. It is prevented that only a specific pixel has a long accumulated lighting time. For that purpose, a gray scale of a display pattern is changed to prevent the difference in deterioration of display element in pixels from increasing. Alternatively, a specific display pattern is prevented from being fixedly displayed in a specific region. Further alternatively, a pixel lagging behind in deterioration is deteriorated so that the accumulated lighting time of pixels is equal to each other.

公开(公告)号：US10319298B2

公开(公告)日：2019-06-11

申请号：US15815774

申请日：2017-11-17

Applicant: Semiconductor Energy Laboratory Co., Ltd.

Inventor： Shunpei Yamazaki ,  Hajime Kimura ,  Atsushi Umezaki ,  Yasunori Yoshida ,  Hideaki Shishido ,  Takuya Kimishima ,  Yasuyuki Arai

IPC: G09G3/3233 ,  G09G3/00 ,  G09G3/20 ,  G09G3/3225

Abstract: In a display element such as an organic EL element, deterioration progresses due to light emission, and emission luminance is lowered even if the same voltage is applied to the display element. Therefore, use over time causes variations in luminance of each pixel, thereby a so-called “image burn-in” phenomenon occurs. Given this factor, the invention provides a display device which can reduce the difference in deterioration of a display element in each pixel and suppress variations in light emission of a display element in a pixel. It is prevented that only a specific pixel has a long accumulated lighting time. For that purpose, a gray scale of a display pattern is changed to prevent the difference in deterioration of display element in pixels from increasing. Alternatively, a specific display pattern is prevented from being fixedly displayed in a specific region. Further alternatively, a pixel lagging behind in deterioration is deteriorated so that the accumulated lighting time of pixels is equal to each other.