High Refractive Index Waveguide for AR
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Augmented Reality (AR) optical waveguides with organic resin-based diffractive gratings degrade in sunlight, have limited durability, and suffer from low diffraction efficiency, resulting in a restricted field of view and high light loss, which limits their usability and visual quality.
Innovation Solution
The development of an AR optical waveguide with a slant etched diffractive grating made from inorganic materials like silicon nitride, hafnium dioxide, or glass, which has a refractive index of 2.0 or greater, is used, allowing for increased durability, improved diffraction efficiency, and resistance to sunlight degradation, and is manufactured using a lithography process for enhanced precision and yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If organic resin-based diffractive gratings are used in AR optical waveguides, then manufacturing is easier and cost is lower, but the waveguide degrades in sunlight and has limited durability
Solution Approach 1:
The patent changes the material parameter from organic resin to inorganic materials (silicon nitride, hafnium dioxide, glass) with refractive indices of 2.0 or greater. This material substitution fundamentally alters the durability and sunlight resistance while maintaining manufacturability through lithography processes.
Solution Approach 2:
The patent employs composite material structures combining inorganic diffractive gratings with transparent substrates having high refractive indices. This composite approach achieves both durability and optical performance, resolving the contradiction between ease of manufacture and reliability.
2Device complexity
If organic resin-based diffractive gratings are used, then manufacturing process is simpler, but diffraction efficiency is low resulting in restricted field of view
Solution Approach 1:
The patent changes the refractive index parameter to 2.0 or greater for inorganic materials, which directly improves diffraction efficiency and expands the field of view. This parameter optimization achieves better performance without significantly increasing device complexity.
3Productivity
If organic resin-based diffractive gratings are used, then production yield is lower, but manufacturing process is less precise
Solution Approach 1:
The patent replaces mechanical imprinting processes with lithography-based manufacturing for inorganic materials. This substitution enables higher manufacturing precision and production yield while maintaining process feasibility, resolving the contradiction between productivity and precision.
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 solution provides a more durable, efficient, and sunlight-resistant AR optical waveguide with increased diffraction efficiency and a broader field of view, significantly improving the usability and visual quality of AR systems.
Implementation Method 1
a slant etched diffractive grating included on the user distal surface of the transparent substrate
Implementation Method 2
The slant etched diffractive grating includes a refractive index of greater than or equal to 2.0. By employing material with a greater refractive index, a greater field of view (FOV) can be achieved
Data Source
Figure 1A~1B
Figure 2~3
Figure 4A
AI summary
Augmented Reality AR optical waveguide (200) includes a transparent substrate (210) including a user proximate surface (210a) and a user distal surface (210b). The AR optical waveguide (200) also includes a slant etched diffractive grating (211) included on the user distal surface (210b) of the transparent substrate (210). The slant etched diffractive grating (211) includes a refractive index of greater than or equal to 2.0.