Apple Inc.

Shengkui Gao

Hyunwoo Nho

Jie Won Ryu

Hung Sheng Lin

Kingsuk Brahma

Sun-il Chang

Junhua Tan

Injae Hwang

Jesse Aaron Richmond

Hyunsoo Kim

Shiping Shen

Wei Hsin Yao

Chaohao Wang

Yafei Bi

Rui Zhang

Paolo Sacchetto

Myungjoon Choi

Chin-Wei Lin

Myung-Je Cho

Mohammad Bagher Vahid Far

Weijun Yao

Mohammad Ali Jangda

Mohammad Hajirostam

Derek Keith Shaeffer

Marc Joseph DeVincentis

Maofeng Yang

Pierre-Yves Emelie

Jiayi Jin

Yue Jack Chu

Sinan Alousi

Yongjun Li

Yun Yu Wang

Shinya Ono

Yi Qiao

Yunhui Hou

Kavinaath Murugan

Warren S Rieutort-Louis

Marc Albrecht

Sang Young Youn

Baris Cagdaser

Koorosh Aflatooni

Sean C Chang

Howard H Tang

Majid Gharghi

Graeme M Williams

Alex H Pai

Haifeng Li

Chih-Wei Yeh

Changki Min

Kasra Omid-Zohoor

Weichuan Yao

Tsung-Ting Tsai

Jean-Pierre Simon Guillou

Peter F Holland

Chieh-Wei Chen

Jun Li

Prashant Mandlik

Shyuan Yang

Zhen Zhang

Yang Xu

Yifan Zhang

Chun Lu

Yuchi Che

Yingying Tang

Rungrot Kitsomboonloha

Shatam Agarwal

Pei-En Chang

Vehbi Calayir

Ross Thompson

Yao Shi

Johan L Piper

James Aamold

Anshi Liang

Rebecca Park

Ce Zhang

Li-Xuan Chuo

Jiye Lee

Jingyu Huang

Zhe Hua

Steven N Hanna

Mario Miscuglio

Hsin-Ying Chiu

Soojin Park

Jesun Kim

Bhadrinarayana L Visweswaran

Chumin Zhao

Sun-II Chang

Katherine W Song

Pyungwoo Yeon

Michael Hong Yeol Lim

In a display characterized by regions with different pixel responses due, for example, to local pixel density variation, voltage-to-luminance matching may be non-universal. Therefore, in order to avoid visual artifacts that may hinder a desired visualization of displayed content, it may be advantageous to compensate the different gamma responses. In some cases, such as with electronic devices having a single pixel density across the display, optical calibration may be performed to determine voltage-to-luminance matching. However, in electronic devices with local pixel density variations, it may be disadvantageous to perform optical calibrations for each region with a different pixel density. Instead of using two distinct gamma curves which may include dedicated optical calibration, a global nonlinear scaler (GNLS) compensation may be applied. Embodiments may pertain to techniques for applying a per-channel and band-global gamma-to-voltage compensation to reduce or minimize a relative luminance error amongst different responses of display regions.

Global nonlinear scaler for multiple pixel gamma response compensation

This disclosure provide various techniques for tracking emission profiles on an electronic display. An emission profile may be applied to the electronic display in order to illuminate certain pixels and deactivate (e.g., turn off) certain pixels in the electronic display to facilitate refreshing (e.g., programming with new image data) the deactivated pixels. A real-time row-based average pixel level or average pixel luminance calculation architecture may track the one or more EM profiles to accurately model EM profile behavior, which may enable accurate calculation of the average pixel level or average pixel luminance of the electronic display at any one point in time. The accurate average pixel level or average pixel luminance calculations effectuated by the EM profile tracking may be used to reduce the IR drop, improve real-time peak-luminance control, and improve the performance of under-display sensors, among other advantages.

Emission profile tracking for electronic displays

A system may include an electronic display panel having pixels, where each pixel may emit light based on a respective programming signal. The system may include a memory storing a map. The processing circuitry may determine a function for each pixel from the map. The processing circuitry may determine a respective control signal based on the function and a target brightness level for each pixel to generate multiple control signals, where the respective control signal is used to generate the respective programming signal for each pixel. The processing circuitry may determine a scaling factor based at least in part on the first map and may scale at least a subset of the multiple control signals based at least in part on the scaling factor.

Configurable pixel uniformity compensation for OLED display non-uniformity compensation based on scaling factors

This disclosure provides various techniques for providing fine-grain digital and analog pixel compensation to account for voltage error across an electronic display. By employing a two-dimensional digital compensation and a local analog compensation, a fine-grain and robust pixel compensation scheme may be provided to the electronic display.

Two-dimensional content-adaptive compensation to mitigate display voltage drop

A system may include an electronic display panel having pixels, where each pixel emits light based on a respective programming signal applied to the pixel. The system may also include processing circuitry to determine a respective control signal upon which the respective programing signal for each pixel is based. The processing circuitry may determine each respective control signal based at least in part on approximations of respective pixel brightness-to-data relationship as defined by a function having variables stored in memory accessible to the processing circuitry.

Dynamic uniformity compensation for electronic display

Systems, methods, and devices are provided for providing intra-frame luminance scaling to avoid drawing excessive power while still providing exceptional brightness. An instantaneous average pixel luminance of an electronic display may be determined. The instantaneous average pixel luminance may correspond to an amount of light currently being emitted by the electronic display due to a previous image frame and a current image frame. Based at least in part on the instantaneous average pixel luminance, the luminance of a subset of pixels of image data of the current image frame may be adjusted, thereby allowing the electronic display to operate at a relatively high brightness level without exceeding a power limit.

Peak luminance control to enable higher display brightness

External compensation of display panels may employ measurement or sensing circuitry configured to measure the output of a pixel and compensate for variations. Due to effects from the sensing circuitry, a mismatch between a target current and the actual current in the pixel may occur. Systems and methods that compensate for the effects from sensing circuitry and reduce or mitigate the mismatch are described. Systems and methods described herein include compensation circuitry that is capable of employing correction factors to compensate for the effects due to the presence of sensing circuitry. Methods for determining the correction factor are also described.

External compensation for displays using sensing and emission differences

A current-voltage (IV) relationship of a pixel having a diode is initially determined. A first voltage is determined that does not cause the diode to emit light, and a first current across the diode is sensed by applying the first voltage. A predetermined current is determined based on the first voltage and the IV relationship. A ratio is determined based on the first current, a target current, and the predetermined current. A ratio voltage is determined by applying the ratio to a predetermined target voltage. If the first current is less than the predetermined current, then the ratio voltage is applied to supply a target current to the diode. If the first current is greater than the predetermined current, then a second voltage is determined by averaging the first test voltage and the ratio voltage, and the second voltage is applied to supply the target current to the diode.

Display compensation using current sensing across a diode without user detection

An electronic device comprises a controller. The controller is configured to provide a first signal to a display of the electronic device to turn off the display. The controller is also configured to provide a second signal to the display to alter a gate source voltage of a drive transistor coupled to a light emitting diode (LED) of a pixel of the display while the display is turned off.

Device and method for panel conditioning

Electronic devices and methods for compensating for aging or other effects in a display during a non-transmitting state (off state) of the display. Sensing may include emissive element sensing of the display and/or thin film transistor sensing of the display. Compensating for the effects may preserve or increase a uniformity of transmission of the display.

Display off-time sensing

A display device may include rows of pixels that display image data on a display and a circuit. The circuit may receive pixel data value of image data for a pixel in a first row of the rows of pixels, determine a weight factor to apply to the pixel data value based on a position of the first row with respect to the other rows, such that each row is associated with a current-resistance (IR) drop across the display. The weight factor is determined based on a respective IR drop associated with the first row. The circuit may also generate a weighted pixel data value based on the weight factor and the pixel data value and send the weighted pixel data value to a display driver circuit that renders the image data via the display.

Systems and methods for compensating for IR drop across a display

A system may include an electronic display panel having multiple pixels for depicting image data and processing circuitry that may receive a first error value representative of a first difference between a first electrical signal measured at a first pixel of the multiple pixels and an expected electrical signal for the first pixel. The first electrical signal may be based on a test signal transmitted to the first pixel and the expected electrical signal may correspond to an expected response of the first pixel based on the test signal. The processing circuitry may filter the first error value to generate a first compensated error value and may filter the first error value based on the first compensated error value to generate a second compensated error value, where the second compensated error value may filter one or more effects of spatial crosstalk between one or more pixels near the first pixel.

Spatially leaking temporal integrator for pixel compensation

Growing community of inventors

San Jose, CA, United States of America

Shengkui Gao