Display panel brightness control based on gaussian edges

Patent metadata

Field	Value
Publication number	US-12387669-B2
Application number	US-202318540613-A
Country	US
Kind code	B2
Filing date	Dec 14, 2023
Priority date	Dec 16, 2022
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

Systems and methods described herein may utilize a non-linear scaling relationship to scale brightness of selective portions of the display in a manner that reduces or eliminates perceivable banding effects. By non-linearly controlling changes in brightness of the display, a viewer may perceive a more uniform, linear dimming towards the relatively dimmer region without perceiving banding, leading to improved user experience when viewing the electronic display.

First claim

What is claimed is:

1. An electronic device comprising:
a display panel configured to display an image, wherein the display panel comprises a first panel section and a second panel section, wherein the second panel section is configured to be dimmed relative to the first panel section, wherein the second panel section comprises a first density of pixels, wherein the first panel section comprises a second density of pixels, and wherein the second density of pixels is greater than the first density of pixels; and
image processing circuitry communicatively coupled to the display panel and to an image source, wherein the image processing circuitry is configured to:
receive, from the image source, first image data corresponding to the second panel section and second image data corresponding to the first panel section;
read a brightness scaling gradient from memory;
adjust the first image data based on the brightness scaling gradient; and
transmit the adjusted first image data and the second image data for presentation via the display panel.

2. The electronic device of claim 1 , wherein the brightness scaling gradient comprises a non-uniform scaling relationship.

3. The electronic device of claim 1 , wherein the brightness scaling gradient comprises a generalized Gaussian scaling relationship.

4. The electronic device of claim 1 , wherein the second panel section spans a width of the display panel.

5. The electronic device of claim 4 , wherein the second panel section shares a boundary with a transition region, and wherein the first panel section shares a boundary with the transition region.

6. The electronic device of claim 5 , wherein the first image data is configured to be presented via a display pixel disposed within the transition region.

7. The electronic device of claim 1 , wherein the first image data is configured to be presented via a display pixel disposed within the second panel section.

8. The electronic device of claim 1 , wherein the image processing circuitry is configured to adjust the first image data based on a first instantaneous average pixel brightness corresponding to the first panel section, a second instantaneous average pixel brightness corresponding to the second panel section, and the brightness scaling gradient.

9. The electronic device of claim 8 , wherein the first image data is adjusted based on the second instantaneous average pixel brightness to ensure that a peak brightness threshold of the second panel section is not exceeded.

10. A method comprising:
receiving first image data configured to be transmitted to a first pixel of a display panel, wherein the first image data corresponds to an image frame to be presented via the display panel;
reading a brightness scaling gradient from memory, wherein the brightness scaling gradient associates a location on the display panel of the first pixel to a scaling parameter to be applied to the first image data;
determining a first instantaneous peak pixel brightness associated with the first pixel;
adjusting the first image data based on the first instantaneous peak pixel brightness and the brightness scaling gradient; and
transmitting the adjusted first image data to the first pixel.

11. The method of claim 10 , wherein reading the brightness scaling gradient from the memory comprises reading the brightness scaling gradient that implements a non-linear brightness scaling via a plurality of scaling parameters including the scaling parameter.

12. The method of claim 10 , wherein reading the brightness scaling gradient from the memory comprises reading the brightness scaling gradient that implements a generalized Gaussian brightness scaling via a plurality of scaling parameters including the scaling parameter.

13. The method of claim 10 , wherein the display panel corresponds to a virtual-reality headset.

14. The method of claim 10 , wherein the display panel corresponds to a mixed-reality headset.

15. The method of claim 10 , wherein the display panel corresponds to a vehicle dashboard.

16. A system, comprising:
a display panel configured to present an image frame via a first panel section of first pixels and a second panel section of second pixels, wherein the first pixels are configured to emit light at a first brightness level, wherein the second pixels are configured to emit light at a second brightness level, wherein the second brightness level is less than the first brightness level, and wherein the second panel section is configured to change dimensions in response to an input received via the display panel; and
image processing circuitry communicatively coupled to the display panel and to an image source, wherein the image processing circuitry is configured to respectively scale image data based on respective locations of each pixel of the second pixels within the display panel to implement a non-linear brightness scaling gradient.

17. The system of claim 16 , wherein the non-linear brightness scaling gradient comprises a generalized Gaussian scaling gradient.

18. The system of claim 16 , wherein the image processing circuitry is configured to update how the non-linear brightness scaling gradient is applied based on the changed dimensions of the second panel section.

19. The system of claim 16 , wherein the non-linear brightness scaling gradient corresponds to a current-dependent brightness scaling gradient, and wherein image data corresponding to the second panel section is scaled based on an expected current output associated with the second panel section.

20. The system of claim 19 , wherein the non-linear brightness scaling gradient comprises an indication of a gain to be applied to the image data to scale the image data, and wherein the gain to be applied to a respective pixel is determined based on sub-pixel data values of that pixel.

Assignees

• Apple Inc

Inventors

• Miscuglio Mario
• Xu Yang
• Jariwala Snehal T
• Qiao Yi
• Guillou Jean-Pierre S
• Hu Jenny
• Xu Ming
• Xin Wanqing
• Xia Zuo
• Zheng Xin
• Ryu Jie Won
• Williams Graeme M
• Brahma Kingsuk

Classifications

• G09G2330/021

  Power management, e.g. power saving · CPC title

• G09G2320/0686

  with two or more screen areas displaying information with different brightness or colours · CPC title

• G09G2340/00

  Aspects of display data processing · CPC title

• G09G2320/0233

  Improving the luminance or brightness uniformity across the screen · CPC title

• G09G3/3208 Primary

  organic, e.g. using organic light-emitting diodes [OLED] · CPC title