Bonded MicroLED Optical Assembly for Fine-Pitch Color Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical devices for wearable electronics, such as smart glasses and HUDs, face challenges in achieving high resolution and brightness due to inefficiencies in pixel size, manufacturing yield, and cost, particularly in creating multi-colored displays from monochromatic LED devices.
Innovation Solution
The development of bonded optical devices where microLEDs are directly bonded to a carrier without an adhesive, using dielectric-to-dielectric bonding techniques, enabling fine pixel pitches of less than 5 microns and allowing for independent control of each LED pixel, which can be combined to produce a multi-colored image.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If adhesive bonding is used to attach optical elements to carrier, then ease of manufacture is improved, but manufacturing precision deteriorates due to inability to achieve fine pixel pitches
Solution Approach 1:
The adhesive layer is extracted and removed from the bonding interface. The patent achieves adhesive-free bonding by directly bonding optical elements (microLEDs) to the carrier substrate without any adhesive intermediary, enabling fine pixel pitches below 5 microns that were not achievable with adhesive bonding methods
Solution Approach 2:
A dielectric material is introduced as an intermediary bonding layer between the optical elements and carrier. This dielectric-to-dielectric bonding approach enables precise alignment and fine pixel pitches while maintaining ease of manufacture through standard semiconductor processing techniques
2Productivity
If monochromatic microLED displays are used, then manufacturing yield is improved, but adaptability deteriorates due to inability to produce multi-colored images
Solution Approach 1:
Multiple monochromatic microLED displays (red, green, blue) are merged and bonded to a common carrier substrate. Each monochromatic layer maintains its manufacturing simplicity and high yield, while their combination through the bonding technique enables full-color display capability
Solution Approach 2:
The display is segmented into separate monochromatic layers (red, green, blue microLEDs) that are manufactured and bonded independently to the carrier. This segmentation allows each layer to be optimized for its specific wavelength while maintaining high manufacturing yield, and the combined effect produces multi-colored images
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
This approach enhances the manufacturability and image quality of wearable displays by enabling smaller pixel pitches, improved brightness, and cost-effectiveness, while maintaining high resolution and efficiency in producing multi-colored images.
Implementation Method 1
The dielectric bonding surfaces can be directly bonded to one another without an adhesive
Data Source
AI summary
A bonded optical device is disclosed. The bonded optical device can include a first optical element, a second optical element, and an optical pathway. The first optical element has a first array of optical emitters configured to emit light of a first color. The first optical element is bonded to at least one processor element, the at least one processor element including active circuitry configured to control operation of the first optical element. The second optical element has a second array of optical emitters configured to emit light of a second color different from the first color. The second optical element is bonded to the at least one processor element. The optical pathway is optically coupled with the first and second optical elements. The optical pathway is configured to transmit a superposition of light from the first and second optical emitters to an optical output to be viewed by users.