Optical Display System with Variable Focal Length Waveguides
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Long-term use of AR or VR display devices leads to eye fatigue due to the constant vergence conflict between dioptric adjustment and vergence rotation, as the viewer's eyes need to adapt to different depths in stereoscopic objects but are constrained by a fixed virtual image plane.
Innovation Solution
An optical display system comprising a light split member that splits light into first and second polarized lights with different polarization directions, guided by first and second optical waveguides, respectively, with adjustable lens assemblies and light valves to control the transmission and focal lengths for alternating near and distant view screens, allowing dioptric and convergence adjustments to align.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fixed virtual image plane is used in AR/VR display devices, then the device structure is simple, but the viewer experiences eye fatigue due to vergence conflict
Solution Approach 1:
The patent implements a variable focal length lens that can dynamically adjust its optical power to change the virtual image plane distance. This allows the display system to transition between different focusing states (near view and distant view), enabling the virtual image plane to move dynamically rather than remaining fixed, thereby resolving the vergence conflict that causes eye fatigue
Solution Approach 2:
The system employs alternating display of near view screens and distant view screens at different focal lengths. By periodically switching between these different virtual image plane distances, the system allows the viewer's eyes to alternate between different vergence and dioptric states, preventing sustained eye strain from maintaining a fixed vergence conflict
2Ease of operation
If polarized light splitting is used to guide light through waveguides, then viewing comfort is improved, but device complexity increases
Solution Approach 1:
The patent combines multiple optical functions into integrated components: the polarizing beam splitter is integrated with the waveguide input, and the variable focal length lens is incorporated within the waveguide system. This merging of functions reduces the overall system complexity despite the advanced optical mechanisms employed
Solution Approach 2:
The waveguide system serves multiple functions simultaneously: it acts as a light guide, a polarizing element, and a focal length adjustment mechanism. The single optical path handles both near view and distant view displays by varying the focal length, eliminating the need for separate optical paths for different viewing modes
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 system reduces eye fatigue by allowing the viewer to continuously receive imaging screens at varying virtual image planes, alleviating the vergence conflict and improving viewing comfort.
Implementation Method 1
a light split member configured to split light from the display screen into a first polarized light and a second polarized light with different polarization directions
Implementation Method 2
a first optical waveguide configured to guide the first polarized light to a light exit side of the optical display system
Implementation Method 3
a second optical waveguide located at a light exit side of the first optical waveguide, spaced apart from the first optical waveguide, and configured to at least partially transmit the first polarized light and guide the second polarized light to the light exit side of the optical display system
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present disclosure provides an optical display system and method, and a display device. The optical display system includes: a display screen; a light split member configured to split light from the display screen into a first polarized light and a second polarized light with different polarization directions; a first optical waveguide configured to guide the first polarized light to a light exit side of the optical display system; and a second optical waveguide located at a light exit side of the first optical waveguide, spaced apart from the first optical waveguide, and configured to at least partially transmit the first polarized light and guide the second polarized light to the light exit side of the optical display system.