Single-Layer Optical Waveguide for Wider AR Field of View
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing AR display technologies face challenges in achieving both a slim and lightweight design and a large field of view, as three-layer waveguides increase thickness while single-layer waveguides limit view, making it difficult to expand the field of view without increasing size.
Innovation Solution
A single-layer optical waveguide structure with multiple coupling-in zones for different colors and a shared coupling-out zone, utilizing binocular complementarity to expand the field of view without increasing thickness, combined with a pupil expansion region and one-dimensional gratings for efficient light coupling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If three layers of waveguides are used to provide a medium to large field of view, then the field of view is improved, but the optical waveguide becomes bulkier
Solution Approach 1:
The patent transitions from a three-layer waveguide structure (vertical stacking in one dimension) to a single-layer waveguide with multiple coupling-in zones arranged in different spatial positions. This dimensional redistribution allows multiple light paths to be managed within a single layer, achieving a large field of view without increasing the waveguide's thickness or volume.
Solution Approach 2:
The patent divides the light coupling function into multiple separate coupling-in zones on the single-layer waveguide. Each coupling-in zone is configured to receive light from different directions or fields of view, and the single-layer waveguide integrates these segmented inputs to achieve a comprehensive large field of view without requiring multiple stacked layers.
2Volume of moving object
If a single-layer optical waveguide is used for RGB, then the design is lightweight and thin, but the field of view is limited and small
Solution Approach 1:
The single-layer waveguide is designed with multiple coupling-in zones that serve different functions: some zones are optimized for wide-angle light coupling to expand the field of view, while others maintain efficient light coupling for color separation. This multi-functional design allows the single layer to simultaneously achieve both a large field of view and lightweight/thin characteristics.
Solution Approach 2:
Different regions (coupling-in zones) on the single-layer waveguide are designed with locally optimized properties. Some zones have grating structures or geometries tailored for wide field-of-view light acceptance, while other zones are optimized for specific color wavelengths. This local quality differentiation enables the single layer to achieve both large field of view and efficient RGB performance.
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 achieves a larger field of view for AR displays by complementing views with binocular superimposition, maintaining a thin and lightweight design, enhancing user experience.
Implementation Method 1
Incident light can be transmitted within the optical waveguide based on the principle of total internal reflection
Implementation Method 2
diffraction gratings are provided on surfaces of the optical waveguide, which are configured to couple light into the interior of the optical waveguide or to couple light out of the optical waveguide
Data Source
AI summary
Embodiments of the present disclosure provide an optical waveguide structure, an optical module and a head-mounted display device; wherein the optical waveguide structure comprises an optical waveguide, and a coupling-out zone and at least two coupling-in zones provided on the optical waveguide; the at least two coupling-in zones are configured for coupling in light of different colors; the coupling-out zone is configured for coupling the light, which has been coupled in through the at least two coupling-in zones, out of the optical waveguide at different field angles, respectively.