Google Inc.

Sangmoo Choi

Sun-il Chang

Ion Bita

Sang Young Youn

Jyothi Karri

David Morris Hoffman

Chang Ju Kang

Wonjae Choi

Yi Zhang

Taesung Kim

Janghoon Song

Yoshimichi Matsuoka

William Riis Hamburgen

Chia-Kai Liang

Ozan Cakmakci

Marek Mienko

Yi Tao

Chien-Hui Wen

Lu Gao

John W Kaehler

Hyunchul Kim

Daniel Solomon

Adrian Gheorghe Manea

Mark Mienko

Jungmin Han

Xiaoping Bai

Choongho Lee

Nai-Hsuan Liu

Jae Won Choi

Sarah S M Cabreros

Rendering images on an active area of an OLED includes rendering images on the active area of the display panel with a plurality of different frame rates. For a plurality of the different frame rates having a frame rate that matches or is above a threshold frame rate, an image refresh operation is performed once per frame period and a self-refresh operation is not performed during the frame period. When rendering images on the active area, for at least one of the different frame rates having a frame rate that is lower than the threshold frame rate, an image refresh operation is performed once per frame period and a self-refresh operation is performed at least once during the frame period.

Power saving in OLED displays with multiple refresh rates

An apparatus includes a display panel having a first pixel area having a first pixel density and a second pixel area having a second pixel density higher than the first, the panel configured to generate images viewable from a front side and a sensor positioned at the back side arranged to receive incident light transmitted from the front to the back through the first pixel area. The first pixel area has light emitting pixels and signal lines electrically connecting pixel circuits associated with the pixels, and the panel includes a layer having a light blocking material patterned to provide apertures to transmit the incident light between some of the light emitting pixels and the signal lines and to block the incident light from the pixel circuits and the signal lines. Apertures can have different dimensions.

Suppressing scattering of light transmitted through OLED displays

The present disclosure provides an electronic device utilizing a flexible display panel with multiple relief features formed in a periphery bending portion of the flexible display panel. The multiple relief features may facilitate lamination of the flexible display to a curved cover layer. The flexible display panel may have a circular shape utilized in a wearable device. An active area for displaying images may extend to the periphery bending portion of the flexible display panel, thus provided a wide viewing range for a user as well as enhancing an overall aesthetic appearance of the electronic device.

Flexible OLED display with reliefs

PWM-frame rate misalignment is mitigated through implementation of a discrete variable refresh rate (VRR) scheme. A target frame rate is limited to a frame rate selected from only those frame rates that facilitate alignment of each frame period to a specified edge of a PWM cycle of a brightness control signal of a display panel. This alignment results in each frame period at the selected frame rate starting at a same point in a corresponding PWM cycle and ending at a same point in a corresponding PWM cycle to help ensure a constant effective duty cycle across each successive frame period, which in turn mitigates perception of flicker that otherwise would arise. Further, the discrete VRR scheme can employ a compensation mode for compensating for the delay in rendering or otherwise obtaining a frame for display so as to maintain a consistent duty cycle in the brightness control signal.

Variable refresh rate control using PWM-aligned frame periods

The subject matter described in this disclosure can be embodied in methods, systems, and program products for operating a display device that includes a pixel array addressed by a set of data lines and a set of scan lines. A method includes: addressing the set of data lines with first image data; sending a first scan signal to a first line of pixels using a first scan line to move the first image data to the first line of pixels; activating the first line of pixels to emit light; sending a second scan signal to a second line of pixels using a second scan line, without having addressed the set of data lines with image data after having addressed the set of data lines with the first image data; and activating the second line of pixels to emit light after the second scan signal has been sent.

Display device with variable image resolution

A mobile computing device includes an emissive display panel configured to emit light from a front surface of the display panel, with the display panel having a plurality of transparent layers and an opaque back cover layer. The mobile computing device also includes a light sensor located behind the opaque back cover layer, and the opaque back cover layer includes an opening through which light from outside the display that is transmitted through the transparent layers of the display can pass to reach the sensor. An air gap separates the light sensor from the transparent layers of the display panel. The plurality of transparent layers includes a reflection attenuating layer on a back side of the display panel configured to attenuate the reflection of light from an interface between a transparent layer of the display panel and the air gap.

OLED display module structure for mitigating dark spot visibility in back cover open regions

In general, the subject matter described in this disclosure can be embodied in methods, systems, and program products for operating a display device. A method of operating a display of a mobile computing device includes transitioning the display of the mobile computing device from a sleep mode to a standby display mode in response to detecting that the mobile computing device tilted by an initial amount; transitioning the display of the mobile computing device from the standby display mode to a normal display mode in response to detecting that the mobile computing device has tilted an additional amount of tilt by a threshold amount of time, the mobile computing device being configured to transition the display from the standby display mode to the sleep mode in response to detecting that the mobile computing device did not tilt the additional amount of tilt by the threshold amount of time.

Display device with variable power consumption

A display device includes a plurality of subpixel emissive areas of a first color, a second color, and a third color arranged in an array having a plurality of rows and columns. Rows of the array include subpixel emissive areas arranged in a repeating pattern of a first color subpixel emissive area, a second color subpixel emissive area, a third color subpixel emissive area, and a second color subpixel emissive area. Alternating columns of the array include subpixel emissive areas: (a) arranged in a repeating pattern of a subpixel emissive area of the first color and a subpixel emissive areas of the third color, and (b) including only subpixel emissive areas of the second color. The display device further includes a plurality of scan lines, a plurality of column lines, and a plurality of electronic subpixel circuits arranged in the array. Each electronic subpixel circuit is configured for receiving electronical signals from a scan line and from a column line and for converting the received signals into a current signal provided to one of the subpixel emissive areas to drive light emission from the subpixel emissive area, where electronic subpixel circuits arranged in a column of the array drive columns of emissive areas having only one color.

Display panel structure with uni-color data lines

The subject matter described in this disclosure includes a pixel circuit with an LED and a driving transistor having a drain terminal that is connected to the LED to supply power to the LED. The pixel circuit also includes a second transistor that is connected between the LED and an initialization voltage line, the second transistor having a gate terminal connected to a scan line. The pixel circuit also includes a third transistor that is connected between the LED and the initialization voltage line in series with the second transistor, the third transistor having a gate terminal connected to a reset line. The pixel circuit is configured so that activating the scan line at a first frequency and activating the reset line at half the first frequency causes the LED to be initialized every other time the scan line is activated.

Display device with consistent luminance at different refresh rates

A display includes subpixel emissive areas of first, second, and third colors arranged in an array that includes rows and columns. The display also includes scan lines, column lines, and electronic subpixel circuits arranged in the array, with each subpixel circuit in a column of the array being electrically connected to a same column line and each electronic subpixel circuit configured for receiving electronic signals from a scan line and from a column line and for converting the received signals into a current signal provided to one of the subpixel emissive areas to drive light emission from the subpixel emissive area. The display further includes demultiplexer (DEMUX) switches, where every other column line of the columns lines is configured to be connected to at least two outputs from a column line driver through the DEMUX switches.

Column interchangeable demultiplexer structure in displays

A display configuration to facilitate imaging through the display is disclosed. The imaging can be achieved by positioning a camera behind a transmit/receive area () of a display. The transmit/receive area is configured to reduce the interaction between the light propagating through the display and circuit elements of the display. The configuration of the transmit/receive area can be characterized by reduced pixel density, rearranged circuit elements (), and as light blocking layer () to prevent light from diffracting from gaps formed by circuit elements ().

Emissive display configured for through-display imaging based on collimator structure

A display device includes subpixels of a first, second, and third colors, scan lines, and column lines. The subpixels are arranged in an array of rows and columns, with each subpixel in a column being electrically connected to a same column line. Each subpixels in a column is configured for receiving electronic scan signals that control a light output from an emissive element of the subpixel from a scan line and from the column line connected to the subpixel. One or more line drivers provide the electronic scan signals, during a time period for rendering a frame, to subpixels in a first set of columns first to subpixels of the first color and then to the subpixels of the third color and to subpixels in a second set of columns first to subpixels of the third color and then to the subpixels of the first color.

Odd and even row sequential driving in AMOLED with pentile arrangement

An example device includes a display panel; a fingerprint sensor configured to sense a fingerprint through the display panel; and processing circuitry configured to: responsive to activation of the fingerprint sensor: activate a local high brightness mode by at least increasing an amount of light radiated from a first portion of the display panel that overlies the fingerprint sensor; and temporarily decrease controlled brightness of a second portion of the display panel that is non-overlapping with the first portion.

Under-display sensor operation

In general, the subject matter described in this disclosure can be embodied in a display panel. The display panel includes a first area of multiple pixels that has a first density of light emitting diodes (LEDs), and that has an equal representation of LEDs of a first color, a second color, and a third color. Each pixel in the first area has: (i) a first sub-pixel comprising an LED of the first color, (ii) a second sub-pixel comprising an LED of the second color, and (iii) a third sub-pixel comprising an LED of the third color. The display panel includes a second area of multiple pixels that borders the first area, that has a second density of LEDs that is lower than the first density, and that has an unequal representation of LEDS of the first color, the second color, and the third color.

Growing community of inventors

Palo Alto, CA, United States of America

Sangmoo Choi