Dual Modulation Display Light Conversion Layer Color Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional display systems using color filters in LCD and OLED displays suffer from significant light wastage, which is converted into harmful heat, degrading performance and increasing manufacturing costs due to the complexity of integrating multiple components.
Innovation Solution
A dual modulation display system with light conversion, utilizing quantum dots or phosphor materials in a light conversion layer, where modulation drive signals are adjusted based on light field simulations to optimize light transmission through subpixels, addressing color non-uniformity and efficiency issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If color filters are used in LCD and OLED displays to modulate light by color, then color reproduction is achieved, but considerable light is wasted and converted into harmful heat
Solution Approach 1:
The patent extracts the color filtering function from traditional absorption-based color filters and replaces it with a light conversion approach using quantum dots or phosphor materials that convert broadband light into specific color wavelengths, thereby eliminating the wastage of blocked light spectra
Solution Approach 2:
The patent changes the fundamental mechanism from light absorption (color filters blocking wavelengths) to light conversion (quantum dots/phosphor transforming wavelengths), fundamentally altering how color is achieved and eliminating the associated energy loss
2Reliability
If color filters are used to block unwanted light spectra, then color purity is improved, but harmful heat is generated degrading display performance and lifetime
Solution Approach 1:
The patent converts the previously harmful heat generation effect into a beneficial approach by using light conversion materials that transform broadband light into useful color wavelengths without generating significant heat, thereby improving reliability and eliminating the harmful thermal effect
3Reliability
If multiple optical, audio, electronic and mechanical components are integrated into a single display system, then display performance is improved, but manufacturing cost increases significantly
Solution Approach 1:
The patent merges the color filtering function with the light emission function by integrating quantum dot or phosphor conversion layers directly into the pixel structure, eliminating the need for separate color filter components and simplifying the overall system integration
Solution Approach 2:
The patent creates a multi-functional pixel structure where the light conversion layer serves both as the color generation mechanism and the light modulation interface, reducing the number of specialized components needed and simplifying manufacturing
4Loss of energy
If light conversion is introduced to a local dimming display architecture, then light efficiency is improved, but color non-uniformity is introduced
Solution Approach 1:
The patent implements feedback mechanisms through light field simulations that model the optical characteristics of the light conversion layer and local dimming architecture, allowing for real-time compensation of color non-uniformity while maintaining high light efficiency
Solution Approach 2:
The patent uses parameter adjustments in the light field simulations to compensate for color non-uniformity by modifying drive signals based on simulated color shift data, thereby achieving uniform color output despite the inherent non-uniformity of the light conversion process
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The dual modulation display system enhances performance by reducing light wastage, improving color accuracy and uniformity, and lowering manufacturing costs through efficient light management and compensation for color shifts and temperature variations.
Implementation Method 1
The light conversion layer can include quantum dots or phosphor materials
Implementation Method 2
The light conversion layer can include quantum dots or phosphor materials
Data Source
Figure 1
Figure 2A~2C
Figure 2D
AI summary
Techniques for driving a dual modulation display include generating backlight drive signals to drive individually-controllable illumination sources. The illumination sources emit first light onto a light conversion layer. The light conversion layer converts the first light, such as blue or ultraviolet light, into second light, such as white light. The light conversion layer can include quantum dot materials. Liquid crystal display (LCD) modulation drive signals are generated to determine transmission of the second light through individual color subpixels of the display. These LCD modulation drive signals can be adjusted based on one or more light field simulations to account for non-uniform, spatial color shifts. The light field simulation can be computed using a plurality of separable 2D point spread functions, where each 2D point spread function can be modeled as two separable ID functions, each ID function being approximated by a sum of limited number of terms.