Apple Inc.

Johan L Piper

James Aamold

Chaohao Wang

Paolo Sacchetto

Hung Sheng Lin

Hyunwoo Nho

Sheng Zhang

Shengkui Gao

Xiaokai Li

Fenghua Zheng

Xiaofeng Wang

David S Zalatimo

Yingying Tang

Yunhui Hou

Nicola Rasera

Chengrui Le

Fabio Ongaro

Vehbi Calayir

James E Brown

Lingyu Hong

Adam Adjiwibawa

Arash Hazeghi

Denis M Darmon

Ming Sun

Sachiko Oda

Robert D Zucker

Li Tao

Systems and methods for electronic displays to use reference voltages to control driving current of illuminators are provided. The reference voltages are used to reduce or eliminate cross talk in driving voltages among different illuminators and driving voltage variations from frame to frame. The transient performance of the driving current of the illuminator (e.g., the current rise/decline time, current overshoot issue, current settling time) may be improved by implementing the reference voltages.

Method and apparatus for LED driver to reduce cross talk or flicker

A device may include an electronic display to display an image frame based on image data. The electronic display may include an illuminator that generates light, multiple light regulators that control emission of the light pixel locations on the electronic display based on bitplane data, and driving circuitry that applies an operating electrical stimulus to the illuminator during an emission period of the image frame and a reference electrical stimulus to the illuminator during an off period of the image frame. While the reference electrical stimulus is applied the bitplane data may be indicative of off bitplane. Additionally, the electronic display may include measurement circuitry that measures a response characteristic of the illuminator in response to the reference electrical stimulus and generates temperature data indicative of the temperature of the illuminator based on the response characteristic.

Direct led temperature sensing systems and methods

Aspects of the subject technology relate to electronic device display circuitry and methods of operating the display. The display circuitry a panel driver interface that decodes digital display data, for each display frame, received from host circuitry of the electronic device. The digital display data includes error correction and detection information for frame and line configuration information distributed in a frame packet and multiple line packets for each display frame. The frame and line configuration information facilitates, efficient, low-error, digital control of various display operational features.

Panel driver interface systems and methods for electronic device displays

Aspects of the subject technology relate to control circuitry for light-emitting diodes (LEDs). The control circuitry may include an LED timing controller integrated circuit configured to receive data from host circuitry for an electronic device, an LED row driver integrated circuit, the LED row driver integrated circuit configured to connect a high voltage power rail to the light-emitting diodes via plurality of switches, and LED column driver integrated circuits each configured to adjust a current through at least one of the light-emitting diodes.

Backlight systems and methods for electronic device displays

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.

Pulsed backlight systems and methods

This application relates to systems, methods, and apparatus for reducing non-uniform luminance of an organic light emitting diode (OLED) display panel. In order to reduce non-uniform luminance, the display panel can compensate for an amount of voltage drop that is occurring across a line of the display panel. The voltage drop can be estimated based on image data provided to the display panel and one or more calibration constants stored by the display panel. The calibration constants can be generated during manufacturing of the display panel in order to equip the display panel with an accurate means for predicting voltage drop across each line of the display panel. During calibration, a predetermined display pattern is output by the display panel. Thereafter, an amount of luminance projected from the display panel is compared with an expected amount of luminance associated with the predetermined display pattern to calculate the calibration constant.

Luminance uniformity correction for display panels

In order to reduce non-uniform luminance and/or chrominance, a display panel can determine, on a pixel-by-pixel basis in at least a row of pixels, a correction for voltage drops in the display panel. The voltage drop can be estimated based on a state of pixels in the display panel corresponding to at least a portion of a current frame of image data and at least a portion of a previous frame of image data. Moreover, based on the correction, the display plane can modify on the pixel-by-pixel basis in at least the row: a supply voltage applied to the display panel; a digital representation of the image data in the current frame that correspond to the pixels; and pixel drive signals corresponding to the image data in the current frame. Furthermore, the correction may be based on a predefined calibration constant and/or may be dynamically calculated.

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Cupertino, CA, United States of America

Johan L Piper