Display Panel Driver for Stress-Based Luminance Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices, such as OLEDs, experience luminance reduction due to the degradation of light emitting elements, which is not adequately compensated for in conventional systems.
Innovation Solution
A display device that generates stress data representing degradation amounts, adjusts input image data, and adjusts a second power supply voltage based on this data to compensate for luminance reduction, using a panel driver with components like a degradation accumulating circuit, degradation compensating circuit, and driving voltage determining circuit to manage luminance and power supply voltages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the driving voltage for light emitting elements is increased to compensate for luminance reduction due to degradation, then the luminance can be maintained, but the power consumption increases
Solution Approach 1:
The patent changes the voltage parameter dynamically by separating power supply voltages into first power supply voltages (for non-degraded pixels) and second power supply voltages (for degraded pixels). The second power supply voltage is set higher to compensate for degradation, while the first remains lower to save power. This selective parameter change resolves the contradiction by applying voltage increases only where necessary.
Solution Approach 2:
The patent applies different power supply voltage levels to different regions (pixels) based on their degradation status. Degraded pixels receive higher second power supply voltages while non-degraded pixels receive lower first power supply voltages. This local differentiation allows luminance maintenance in degraded areas without increasing power consumption across the entire display.
2Illumination intensity
If the driving voltage for light emitting elements is increased to compensate for luminance reduction, then the luminance can be maintained, but the light emitting element degradation accelerates
Solution Approach 1:
The patent applies higher second power supply voltages only to degraded pixels that need luminance compensation, while non-degraded pixels continue to operate at lower first power supply voltages. This localized approach maintains luminance where needed without subjecting all elements to increased stress, thereby slowing overall degradation and improving reliability.
Solution Approach 2:
The patent applies excessive voltage (second power supply voltage higher than first) only partially to degraded pixels rather than uniformly to all pixels. This partial application provides sufficient compensation for luminance reduction in degraded areas while avoiding unnecessary over-stressing of non-degraded elements, thus balancing luminance maintenance with degradation prevention.
3Device complexity
If uniform power supply voltage is applied to all pixels, then the circuit design is simple, but luminance uniformity deteriorates as degradation occurs
Solution Approach 1:
The patent implements local quality differentiation by providing different first and second power supply voltage levels to different pixels based on degradation status. The pixel circuit includes switching elements that can select between these voltage levels, enabling luminance uniformity across degraded and non-degraded pixels while managing circuit complexity through systematic voltage selection.
Solution Approach 2:
The patent introduces dynamic voltage selection capability where pixels can switch between first and second power supply voltages based on their degradation state. This dynamic approach allows the system to adapt to varying degradation conditions and maintain luminance uniformity, transforming a static uniform voltage system into a flexible adaptive system.
Data Source
AI summary
A display device including: a display panel including a plurality of pixels; and a panel driver connected to the display panel, the panel driver configured to generate stress data representing a degradation amount of the display panel, to generate corrected image data by adjusting input image data based on the stress data, to determine a luminance of the display panel based on a display brightness value or the corrected image data, to adjust a second power supply voltage based on the stress data and the luminance of the display panel, and to drive the display panel based on the corrected image data, a first power supply voltage and the second power supply voltage.