Pretilted Liquid Crystal Polarization Switches for Wide-FOV Optics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional augmented reality (AR) and virtual reality (VR) systems struggle to provide a comfortable and realistic presentation of virtual image elements amidst real-world imagery due to mismatches between accommodative and vergence states, leading to user discomfort.
Innovation Solution
The use of adaptive lens assemblies with switchable waveplates between waveplate lenses, allowing variable optical power and polarization state switching, to modify wavefront divergence and provide multiple virtual depth planes, reducing thickness and weight while enhancing depth perception.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional AR/VR systems use fixed optical power lenses, then the system structure is simple, but the accommodation-vergence matching is poor causing user discomfort
Solution Approach 1:
The patent applies dynamics by making the optical power of the lens assembly switchable between multiple states (first optical power and second optical power) rather than fixed. This allows the system to dynamically adjust wavefront divergence to match vergence cues, providing physiologically correct accommodation-vergence matching that eliminates user discomfort while maintaining manageable system complexity through controlled switching between discrete states.
Solution Approach 2:
The patent changes the optical parameter (optical power) of the lens assembly between at least two different states. By switching between a first optical power and a second optical power, the system can provide different wavefront divergences that correspond to different virtual depth planes, enabling proper accommodation-vergence matching without requiring a completely complex optical structure.
2Reliability
If multiple waveguide assemblies are used to provide multiple depth planes, then depth perception is enhanced, but the thickness and weight of the device increase
Solution Approach 1:
The patent merges the functions of multiple waveguide assemblies into a single waveguide assembly by combining it with a switchable lens assembly. Instead of using separate waveguide assemblies for different depth planes, the invention integrates multiple virtual depth plane functionality into one assembly through optical power switching, thereby providing enhanced depth perception while reducing overall device thickness and weight.
Solution Approach 2:
The single waveguide assembly is designed to perform multiple functions by switching between different optical power states. The lens assembly can provide different wavefront divergences corresponding to multiple virtual depth planes, making the single assembly universal for creating various depth effects that would otherwise require multiple separate assemblies, thus reducing device weight and thickness.
3Ease of operation
If adaptive lens assemblies with switchable waveplates are used, then accommodation-vergence matching is improved, but the device complexity increases
Solution Approach 1:
The patent replaces complex mechanical adjustment mechanisms with a switchable waveplate-based optical system. Instead of using mechanical means to adjust lens power continuously, the invention uses electro-optic or photo-optic switching of waveplates to change optical power between discrete states, thereby improving user comfort through better accommodation-vergence matching while keeping the control mechanism relatively simple and avoiding complex mechanical structures.
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 simplifies driving mechanisms, reduces computational power, and enhances user comfort by providing physiologically correct accommodation-vergence matching, resulting in a more realistic and comfortable three-dimensional imagery experience.
Implementation Method 1
a liquid crystal layer comprising molecules that are tilted with increasing outward radial distance from a central axis
Implementation Method 2
increases the angle at which light is incident on the liquid crystal layer
Data Source
Figure 1
Figure 2
Figure 3A~3C
AI summary
A switchable optical assembly comprises a switchable waveplate configured to be electrically activated and deactivated to selectively alter the polarization state of light incident thereon. The switchable waveplate comprises first and second surfaces and a liquid crystal layer disposed between the first and second surfaces. The first liquid crystal layer comprises a plurality of liquid crystal molecules. Said first and second surfaces may be curved. Said plurality of liquid crystal molecules may vary in tilt with respect to said first and second surfaces with outward radial distance from an axis through said first and second surfaces and said liquid crystal layer in a plurality of radial directions. The switchable waveplate additionally comprises a first plurality of electrodes to apply an electrical signal across said first liquid crystal layer.