Compact Homogenizer for Wearable Display Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wearable display systems are often heavy, large, and lack uniform brightness, making them unsuitable for stealthy, high-resolution, see-through viewing, and are costly to produce, with existing illumination systems failing to efficiently combine multiple color light sources into a compact form factor.
Innovation Solution
An ultra-compact flat homogenizer and diffuser based on a Fresnel lens waveguide and cube Polarized Beam Splitter (PBS) is used to provide uniform illumination for wearable displays, combining RGB LED light sources and enabling total-internal-reflection for parallel and homogeneous light distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If conventional illumination systems with multiple light sources and homogenizers are used, then uniform brightness can be achieved, but the device becomes large and heavy
Solution Approach 1:
The patent combines multiple light sources (RGB LEDs) and the homogenizing function into a single integrated illumination device. The homogenizer and light sources are merged into one compact unit, eliminating the need for separate components and reducing overall device weight while maintaining uniform brightness distribution.
Solution Approach 2:
The illumination device serves multiple functions simultaneously: it generates light from multiple color sources, combines them into a single beam, homogenizes the light distribution, and directs it to the display device. This multi-functionality eliminates the need for separate components for each function, reducing device size and weight.
2Illumination intensity
If conventional illumination systems with homogenizer and combiner are used, then uniform light distribution is achieved, but the device size increases
Solution Approach 1:
The homogenizer and light combining functions are merged into a single integrated optical path. The illumination device combines multiple light sources and homogenizes them within the same compact structure, eliminating the need for separate homogenizer and combiner components, thus reducing device length.
Solution Approach 2:
The patent employs a nested arrangement where the homogenizing optical elements are positioned within the illumination device housing, and the light sources are nested within the homogenizer structure. This nesting allows multiple functional components to occupy overlapping or adjacent spaces, minimizing the overall device footprint.
3Adaptability or versatility
If separate color light sources are used to achieve full color display, then color quality is improved, but device complexity increases
Solution Approach 1:
The patent merges three separate color light sources (RGB LEDs) into a single integrated illumination device with a unified optical path. The homogenizer combines all three color beams simultaneously within the same device, eliminating the need for separate handling of each color channel and reducing system complexity while maintaining full color capability.
Solution Approach 2:
The single illumination device performs multiple functions: generating three different colors, combining them into one beam, homogenizing the combined light, and directing it to the display. This universal design replaces what would otherwise require multiple separate systems, reducing overall complexity.
4Volume of moving object
If compact illumination system is used to reduce device size, then portability is improved, but light uniformity deteriorates
Solution Approach 1:
The homogenizer in the patent uses optical elements with spatially varying properties to redistribute light uniformly across the output aperture. By optimizing the local optical properties at different positions within the compact homogenizer, uniform light distribution is achieved despite the reduced overall device volume.
Solution Approach 2:
The integration of light sources and homogenizing functions in a single compact device allows for optimized light distribution pathways. The homogenizer is designed to efficiently mix and redistribute light from all color sources uniformly across the small output area, maintaining light uniformity despite the compact form factor.
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 configuration results in a lightweight, compact, high-resolution wearable display with uniform brightness, suitable for stealthy use and cost-effective production, by efficiently combining and distributing light for see-through viewing.
Implementation Method 1
enabling total-internal-reflection for parallel and homogeneous light distribution
Implementation Method 2
Fresnel lens waveguide
Implementation Method 3
cube Polarized Beam Splitter (PBS)
Data Source
AI summary
A compact light source for a projection display is disclosed enabling eye-glass display using a Fresnel mirror reflecting light without a distance as conventional prism type reflector.