公开(公告)号：US20190244572A1

公开(公告)日：2019-08-08

申请号：US16265902

申请日：2019-02-01

Applicant: Apple Inc.

Inventor： Chengrui LE ,  Chaohao Wang ,  Li Tao ,  Lingyu Hong ,  Paolo Sacchetto ,  Sheng Zhang ,  Xiaokai Li ,  Yingying Tang ,  Yunhui Hou ,  Johan L. Piper

IPC: G09G3/34 ,  G09G3/36

CPC classification number: G09G3/3406 ,  G09G3/342 ,  G09G3/36 ,  G09G2320/0247 ,  G09G2320/0261 ,  G09G2320/041 ,  G09G2320/0606 ,  G09G2320/062 ,  G09G2320/0633 ,  G09G2320/064 ,  G09G2320/0646 ,  G09G2320/103 ,  G09G2340/0435 ,  G09G2354/00 ,  G09G2360/16

Abstract: Aspects of the subject technology relate to pulsed backlight operation for a display backlight. Backlight pulse patterns are provided that include steady state pulse patterns to be applied during operation of a liquid crystal display unit of the display at a corresponding frame rate. The backlight pulse patterns can be arranged to prevent visible artifacts such as flicker or strobing, particularly at or near a transition between LCD frame rates. In some scenarios, transition pulse patterns are provided,

公开(公告)号：US20180075801A1

公开(公告)日：2018-03-15

申请号：US15404139

申请日：2017-01-11

Applicant: Apple Inc.

Inventor： Chengrui LE ,  Chaohao Wang ,  Kingsuk Brahma ,  Jie Won Ryu ,  Chin-Wei Lin ,  Rui Zhang

IPC: G09G3/3233 ,  G09G3/3258

Abstract: Aspects of the subject technology relate to electronic devices with displays. A display may include an array of display pixels each having a drive transistor and an organic light-emitting diode. A pulse-width-modulated current may be provided to the organic light-emitting diode during each display frame to compensate for an on-bias compensation applied to the drive transistor between display frames. The pulse-width-modulated current may be provided with a pulse-width-modulation ratio that decreases over the course of each display frame. The decrease of the pulse-width-modulation ratio for each display frame may be determined based on a peak luminance for that display frame. The reduction in flicker provided by the pulse-width-modulated current may facilitate operation of the display with a reduced refresh rate, thereby reducing power consumption by the display.