Diffraction Light Guide Plate With Stress Compensation Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing diffraction light guide plates for Augmented Reality (AR), Mixed Reality (MR), and Virtual Reality (VR) displays are thick and heavy, and the substrate can be transformed by stress from the pattern layer, leading to degraded display performance due to light scattering and image quality issues.
Innovation Solution
A diffraction light guide plate is designed with a first diffraction substrate having a first diffraction grating layer on one surface and a second diffraction grating layer on the other, and a second diffraction substrate with a third diffraction grating layer and a stress compensation layer on the other surface, which separates light within specific wavelength ranges and compensates for stress, reducing thickness and weight while preventing substrate transformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If three substrates are used to form the diffraction light guide plate, then the light diffraction function is improved, but the thickness and weight of the device increase
Solution Approach 1:
The patent combines multiple diffraction grating layers onto fewer substrate(s) by forming first, second, and third diffraction grating layers on the same substrate surface. This merging approach maintains the light diffraction functionality while reducing the number of substrates from three to one or two, thereby decreasing the overall weight and thickness of the diffraction light guide plate.
2Reliability
If pattern layer is formed on one surface of substrate, then the diffraction function is achieved, but the substrate is transformed by stress of the pattern layer
Solution Approach 1:
The patent applies preliminary anti-action by forming a stress compensation layer on the substrate that has stress characteristics opposite to and equal in magnitude to the stress generated by the diffraction grating pattern layer. This pre-compensation prevents substrate transformation and maintains substrate stability while preserving the diffraction function.
3Measurement precision
If multiple diffraction grating layers are formed on separate substrates, then light separation efficiency is improved, but device complexity increases
Solution Approach 1:
The patent merges multiple diffraction grating layers (first, second, and third diffraction grating layers with different wavelength separation characteristics) onto the same substrate surface. This integration maintains the light separation efficiency for different wavelength ranges while significantly reducing device complexity by eliminating the need for multiple separate substrates and their associated alignment and assembly requirements.
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 solution effectively decreases the thickness and weight of the diffraction light guide plate, improves light separation efficiency, and suppresses substrate transformation due to stress, enhancing display performance by preventing light scattering and maintaining image quality.
Implementation Method 1
a diffraction light guide plate using a diffraction phenomenon based on a wave property of light
Implementation Method 2
the first diffraction grating layer separates light having a wavelength of 550 nm or more and 700 nm or less, the second diffraction grating layer separates light having a wavelength of 400 nm or more and 550 nm or less, the third diffraction grating layer separates light having a wavelength of 450 nm or more and 650 nm or less
Data Source
AI summary
A diffraction light guide plate, including: a first diffraction substrate; and a second diffraction substrate provided on the first diffraction substrate. The first diffraction substrate includes a first diffraction grating layer on one surface and a second diffraction grating layer on an opposite surface. The second diffraction substrate includes a third diffraction grating layer on one surface and a stress compensation layer on an opposite surface. The first diffraction grating layer separates light having a wavelength of 550 nm or more and 700 nm or less, the second diffraction grating layer separates light having a wavelength of 400 nm or more and 550 nm or less, the third diffraction grating layer separates light having a wavelength of 450 nm or more and 650 nm or less, and the stress compensation layer has stress in the same direction as a direction of stress of the third diffraction grating layer.