EP-4738324-A1 - DISPLAY CONTROLLER FOR AGING COMPENSATION

EP4738324A1EP 4738324 A1EP4738324 A1EP 4738324A1EP-4738324-A1

Abstract

This disclosure generally relates to a display controller, a method, a display system, and a computer program and more specifically to ways of compensating for aging effects of a display device.

Inventors

STAUDENMAIER, Michael Andreas
Haelsing, Sven
AUBINEAU, Vincent

Assignees

NXP B.V.

Dates

Publication Date: 20260506
Application Date: 20241031

Claims (15)

A display controller comprising: an image data interface for obtaining first image data from a first frame buffer; a temperature data interface for obtaining a first temperature datum from a first temperature sensor; an aging compensation quantity interface for obtaining a first aging compensation quantity for a first color component of a first pixel from a first memory element; a processing unit configured for rendering display data at a display refresh frequency, wherein the processing unit is configured to: determine a first initial intensity of the first color component of the first pixel based on the first image data, determine a first corrected intensity of the first color component of the first pixel based on the first initial intensity of the first color component of the first pixel and the first aging compensation quantity, and determine a first incremental aging effect datum for the first color component of the first pixel based on (i) the first initial intensity or the first corrected intensity of the first color component of the first pixel and (ii) the first temperature datum; and a display data interface for outputting the display data comprising the first corrected intensity of the first color component of the first pixel to a display device at the display refresh frequency.
The display controller of claim 1, wherein the display device comprises light emitting diodes.
The display controller according to any of the preceding claims, wherein the first aging compensation quantity comprises at least one coefficient of a polynomial.
The display controller according to any of the preceding claims, further comprising an aging accumulator wherein the aging accumulator is configured to update, at the display refresh frequency, a first intermediate accumulated aging effect datum based on the first incremental aging effect datum; and wherein the aging accumulator is further configured to update a first accumulated aging effect datum based on the first intermediate accumulated aging effect datum at a lifetime accumulation frequency that is lower than the display refresh frequency and / or triggered by a first user-initiated action.
The display controller according to any of claims 1 to 3, further comprising an aging accumulator wherein the aging accumulator is configured to update a first accumulated aging effect datum based on the first incremental aging effect datum at the display refresh frequency.
The display controller according to claim 4 or 5, wherein: the processing unit is further configured to update the first aging compensation quantity for the first color component of the first pixel based on the first accumulated aging effect datum; wherein the update of the first aging compensation quantity is triggered by a second user-initiated action and / or performed periodically at an update frequency, wherein the update frequency is lower than the display refresh frequency.
The display controller of any of the preceding claims, wherein the aging compensation quantity interface is further configured for obtaining a second aging compensation quantity for a second color component of the first pixel from the first memory element and a third aging compensation quantity for a third color component of the first pixel from the first memory element; wherein the processing unit is further configured to: determine a second initial intensity of the second color component of the first pixel based on the first image data, and determine a third initial intensity of the third color component of the first pixel based on the first image data, determine a second corrected intensity of the second color component of the first pixel based on the second initial intensity of the second color component of the first pixel and the second aging compensation quantity, and determine a third corrected intensity of the third color component of the first pixel based on the third initial intensity of the third color component of the first pixel and the third aging compensation quantity, determine a second incremental aging effect datum for the second color component of the first pixel based on the second initial intensity or the second corrected intensity of the second color component of the first pixel and the first temperature datum; determine a third incremental aging effect datum for the third color component of the first pixel based on the third initial intensity or the third corrected intensity of the third color component of the first pixel and the first temperature datum; wherein the display data interface is further configured for outputting display data comprising the second corrected intensity of the second color component and the third corrected intensity of the third color component of the first pixel to the display device at the display refresh frequency.
The display controller according to claim 7, wherein the aging accumulator is further configured to update, at the display refresh frequency, a second intermediate accumulated aging effect datum based on the second incremental aging effect datum, and wherein the aging accumulator is further configured to update a second accumulated aging effect datum based on the second intermediate accumulated aging effect datum periodically at the lifetime accumulation frequency and / or triggered by the first user-initiated action; and wherein the aging accumulator is further configured to update, at the display refresh frequency, a third intermediate accumulated aging effect datum based on the third incremental aging effect datum, and wherein the aging accumulator is further configured to update a third accumulated aging effect datum based on the third intermediate accumulated aging effect datum at the lifetime accumulation frequency and / or triggered by the first user-initiated action.
The display controller according to claim 7, wherein the aging accumulator is further configured to update a second accumulated aging effect datum based on the second incremental aging effect datum at the display refresh frequency, and wherein the aging accumulator is further configured to update a third accumulated aging effect datum based on the third incremental aging effect datum at the display refresh frequency.
The display controller according to claim 8 or 9, wherein the processing unit is further configured to update the second aging compensation quantity for the second color component of the first pixel based on the second accumulated aging effect datum, and wherein the processing unit is further configured to update the third aging compensation quantity for the third color component of the first pixel based on the third accumulated aging effect datum; wherein the update of the second and third aging compensation quantity is triggered by the second user-initiated action and / or performed periodically at an update frequency, wherein the update frequency is lower than the display refresh frequency.
The display controller of any of claims 1 to 6, wherein the image data interface is further configured for obtaining second image data from a second frame buffer and wherein the processing unit is configured to determine the first initial intensity of the first color component of the first pixel based on the first image data and the second image data.
The display controller according to claim 11 and any of claims 7 to 10, wherein the processing unit is configured to: determine the second initial intensity of the second color component of the first pixel based on the first image data and the second image data, and determine the third initial intensity of the third color component of the first pixel based on the first image data and the second image data.
A display system comprising: a display controller according to any of the preceding claims, a display connectable to the display data interface of the display controller, the first memory element, the first frame buffer, and the temperature sensor.
A method performed by a display controller comprising: obtaining first image data from a first frame buffer via an image data interface; obtaining a first temperature datum from a temperature sensor; obtaining a first aging compensation quantity for a first color component of a first pixel from a first memory element via an aging compensation quantity interface; rendering, by a processing unit of the display controller, display data at a display refresh frequency, the rendering comprising: determining a first initial intensity of the first color component of the first pixel based on the first image data, determining a first corrected intensity of the first color component of the first pixel based on the first initial intensity of the first color component of the first pixel and the first aging compensation quantity, and determining a first incremental aging effect datum for the first color component of the first pixel based on (i) the first initial intensity or the first corrected intensity of the first color component of the first pixel and (ii) the first temperature datum; and outputting, via a display data interface, the display data comprising the first corrected intensity of the first color component of the first pixel to a display device at the display refresh frequency.
A computer program comprising instructions that, when executed by a display controller, causes the display controller to perform a method according to claim 14.

Description

TECHNICAL FIELD This disclosure generally relates to a display controller, a method, a display system, and a computer program and more specifically to ways of compensating for aging effects of a display device. BACKGROUND The pixels in various types of displays can exhibit a significant aging effect. Over time, the intensity of the pixels degrades. This degradation may depend on several parameters, such as the color of the pixel, the amount of usage of the pixel, e.g. how long it has been used and at what intensity, and at what temperatures the pixel has been operated. Since the degradation may be dependent on pixel color, as time goes by, the color temperature of the display may change. For example, a screen that was initially white at the beginning of its life might increasingly get color cast over time. SUMMARY According to a first aspect of the present disclosure, there is provided a display controller comprising: an image data interface for obtaining first image data from a first frame buffer;a temperature data interface for obtaining a first temperature datum from a first temperature sensor;an aging compensation quantity interface for obtaining a first aging compensation quantity for a first color component of a first pixel from a first memory element;a processing unit configured for rendering display data at a display refresh frequency, wherein the processing unit is configured to: determine a first initial intensity of the first color component of the first pixel based on the first image data,determine a first corrected intensity of the first color component of the first pixel based on the first initial intensity of the first color component of the first pixel and the first aging compensation quantity, anddetermine a first incremental aging effect datum for the first color component of the first pixel based on (i) the first initial intensity or the first corrected intensity of the first color component of the first pixel and (ii) the first temperature datum;a display data interface for outputting the display data comprising the first corrected intensity of the first color component of the first pixel to a display device at the display refresh frequency. In one or more embodiments, the display device comprises light emitting diodes. In one or more embodiments, the first aging compensation quantity may comprise at least one coefficient of a polynomial. In one or more embodiments, the display controller further comprises an aging accumulator wherein the aging accumulator is configured to update, at the display refresh frequency, a first intermediate accumulated aging effect datum based on the first incremental aging effect datum; and wherein the aging accumulator is further configured to update a first accumulated aging effect datum based on the first intermediate accumulated aging effect datum at a lifetime accumulation frequency that is lower than the display refresh frequency and / or triggered by a first user-initiated action. In one or more embodiments, the display controller further comprises an aging accumulator wherein the aging accumulator is configured to update a first accumulated aging effect datum based on the first incremental aging effect datum at the display refresh frequency. In one or more embodiments, the processing unit is further configured to update the first aging compensation quantity for the first color component of the first pixel based on the first accumulated aging effect datum; wherein the update of the first aging compensation quantity is triggered by a second user-initiated action and / or performed periodically at an update frequency, wherein the update frequency is lower than the display refresh frequency. In one or more embodiments, the aging compensation quantity interface is further configured for obtaining a second aging compensation quantity for a second color component of the first pixel from the first memory element and a third aging compensation quantity for a third color component of the first pixel from the first memory element; wherein the processing unit is further configured to: determine a second initial intensity of the second color component of the first pixel based on the first image data, anddetermine a third initial intensity of the third color component of the first pixel based on the first image data,determine a second corrected intensity of the second color component of the first pixel based on the second initial intensity of the second color component of the first pixel and the second aging compensation quantity, anddetermine a third corrected intensity of the third color component of the first pixel based on the third initial intensity of the third color component of the first pixel and the third aging compensation quantity,determine a second incremental aging effect datum for the second color component of the first pixel based on the second initial intensity or the second corrected intensity of the second color component of the first pixel and t