Polychromic MicroLED Pixel Layout With Yellow for Higher Efficacy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LED technologies face challenges in achieving high power efficiency and large RGB color gamut, particularly due to the inefficiency of red and blue pixels, which require higher drive power and limit color synthesis flexibility.
Innovation Solution
Incorporating a fourth pixel with higher luminous efficacy, emitting yellow light on the red-green locus, alongside traditional RGB pixels, to enhance power efficiency and expand the color gamut.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If traditional RGB pixels are used, then color synthesis is achieved, but power efficiency is limited due to inefficiency of red and blue pixels
Solution Approach 1:
The pixel array is segmented into four distinct color types (red, green, blue, and yellow) instead of traditional three colors. Each color pixel type is independently controlled and optimized, allowing the yellow pixels to handle luminance-intensive tasks while RGB pixels maintain color synthesis capabilities, thereby improving overall power efficiency without sacrificing color synthesis flexibility.
Solution Approach 2:
The patent adds a fourth color dimension (yellow) to the traditional RGB three-color system. This dimensional expansion creates a RGBY color space that provides both improved power efficiency through yellow pixels' higher luminous efficacy and enhanced color synthesis capability through the extended color gamut.
2Adaptability or versatility
If red and blue pixels are used for color synthesis, then RGB color gamut is achieved, but drive power requirements increase
Solution Approach 1:
Yellow pixels serve as an intermediary element between the blue excitation source and the final color output. By using yellow phosphor materials with high luminous efficacy to convert blue light, the system reduces the drive power needed for blue pixels while maintaining or enhancing the overall color gamut through the yellow emission component.
3Use of energy by moving object
If yellow pixel is added to improve power efficiency, then power efficiency increases, but device complexity increases
Solution Approach 1:
The patent merges the yellow pixel technology with existing RGB microLED fabrication processes. By integrating yellow phosphor materials into the blue pixel structure or combining yellow and blue pixels in a unified substrate, the design achieves improved power efficiency while minimizing the increase in device complexity through shared manufacturing infrastructure.
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 addition of a yellow pixel with higher luminous efficacy improves power efficiency and enables a larger RGB color gamut without increasing process time in mass-transfer die attach, making it suitable for uLED display applications.
Implementation Method 1
light emitting layers of different colors
Data Source
AI summary
A light-emitting diode (LED) die comprises: a plurality of pixels, each of the pixels comprising respective groups of epitaxial stacks included in a microLED comprising one or more tunnel junctions and light emitting layers of different colors, the plurality of pixels comprising: a first set of pixels configured to emit a red light; a second set of pixels configured to emit a green light; a third set of pixels configured to emit a blue light; the red light, the green light, and the blue light defining a RGB (red-green-blue) gamut; and a fourth set of pixels configured to emit a yellow light and to increase power efficiency of the device over that of a device with only RGB pixels.