Apple Inc.

Michael H Lim

Kyung Hoae Koo

Weijun Yao

David Andrew Doyle

Jiayi Jin

Chuang Qian

Yue Jack Chu

Tsung-Ting Tsai

Paolo Sacchetto

Abbas Jamshidi Roudbari

Timothy Michael Johnson

Warren S Rieutort-Louis

Christophe Blondin

Yifan Zhang

Yuchi Che

Tae-Wook Koh

Mahdi Nezamabadi

Maofeng Yang

Ashray Vinayak Gogte

Venkatesh Rajendran

Ricardo A Peterson

Jared S Price

Ruo-Gu Huang

Akshay Bhat

Yurii Morozov

Sebastian Knitter

Matthew Dominic Hollands

Kenny Kim

Matthew J Schwendeman

Wanglei Han

Yue Qu

A display may have both a full pixel density region and a pixel removal region with a plurality of high-transmittance areas that overlap an optical sensor. Each high-transmittance area may be devoid of thin-film transistors and other display components. To improve transmission while maintaining satisfactory touch sensing performance, one or more segments of the touch sensor metal in the pixel removal region may have a reduced width relative to the touch sensor metal in the full pixel density region and/or one or more segments of the touch sensor metal in the pixel removal region may be omitted relative to the touch sensor metal in the full pixel density region. To mitigate a different appearance between the pixel removal region and the full pixel density region at off-axis viewing angles, the position of the touch sensor metal in the pixel removal region may be tuned.

Devices with displays having transparent openings and touch sensor metal

A display may include pixels (such as light-emitting diode pixels) that are susceptible aging effects (burn-in). To help avoid visible artifacts caused by burn-in during operation of the display, compensation circuitry may be used to compensate image data for the display. An optical sensor may be included behind the pixels to directly measure pixel brightness levels. The optical sensor may provide optical sensor data from testing operations to the compensation circuitry. The optical sensor may gather data during burn-in testing operations. During the burn-in testing operations, pixel groups including both high-usage pixels and low-usage pixels may sequentially emit light while the optical sensor gathers data. Brightness differences between the high-usage pixels and low-usage pixels may be used to characterize pixel aging in the display and compensate image data to mitigate visible artifacts caused by burn-in. The optical sensor may also gather data during global brightness testing operations.

Display with optical sensor for brightness compensation

A display may have an array of organic light-emitting diode display pixels. Each display pixel may include a drive transistor coupled in series with one or more emission transistors and a respective organic light-emitting diode (OLED). A semiconducting-oxide transistor may be coupled between a drain terminal and a gate terminal of the drive transistor to help reduce leakage during low-refresh-rate display operations. To compensate for variations in the threshold voltage of the semiconducting-oxide transistor, the magnitude of a high voltage level of a scan control signal provided to the gate terminal of the semiconducting-oxide transistor may be adjusted. Sensing circuitry may be used to sense a display current while displaying a calibration image. The sensed display current may be compared to an expected display current associated with the calibration image. Processing circuitry may update the high voltage level based on the actual display current compared to the expected display current.

Electronic devices having displays with compensation for oxide transistor threshold voltage

A display driver is disclosed that reduces first frame dimming and flicker in light-emitting diode pixels of a display device. The display driver may receive a display brightness value and determine a value of a dynamic supply voltage parameter based on the display brightness value. Over a first time interval, the display driver may apply a supply voltage that is based on the dynamic supply voltage parameter to one of a gate of a drive transistor of a light-emitting-diode circuit and a channel of the drive transistor. Over a second time interval, the display driver may apply a parking voltage to an anode of a light-emitting diode of the light-emitting-diode circuit and to the channel of the drive transistor. The value of the parking voltage may be below a threshold voltage of the light-emitting diode and correspond to the value of the dynamic supply voltage parameter.

Adaptive parking voltage tuning to optimize display front-of-screen with dynamic supply voltage

Growing community of inventors

Cupertino, CA, United States of America

Michael H Lim