Optical Combiner With Tunable Tint Layer For Stray Light Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical systems that combine computer-generated and real-world images face performance issues due to stray light reflections and excessive external light, which can interfere with the merging of image light from displays with real-world light.
Innovation Solution
The use of an optical combiner with a tunable tint layer and reflective polarizer components, such as a circular polarizer and reflective polarizer, to selectively adjust light transmission and suppress stray reflections, while a concave lens-shaped reflector redirects and focuses display image light towards the viewer's eyes without distorting real-world image light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If an optical combiner is used to merge display image light with real-world image light, then both computer-generated and real-world images can be viewed simultaneously, but stray light reflections in the optical combiner can adversely affect system performance
Solution Approach 1:
The patent applies circular polarizers to convert the harmful stray light reflections into beneficial polarized light transmission. The circular polarizers are positioned to overlap the display but not overlap the real-world image light path, allowing them to filter reflected light from the display while permitting real-world light to pass through unaffected. This transforms the problematic reflections into a controlled polarized state that can be managed by the optical system.
Solution Approach 2:
The patent implements different optical properties in different regions of the optical combiner. Circular polarizers are applied selectively to specific areas where display light reflections occur, while leaving other regions transparent for real-world light transmission. This localized application ensures that stray light suppression is applied only where needed, maintaining overall system performance and avoiding unnecessary interference with the real-world image path.
2Object-affected harmful factors
If excessive light from external objects enters the optical system, then it can interfere with the merging of image light, but blocking external light can reduce the quality of real-world image transmission
Solution Approach 1:
The patent introduces circular polarizers as intermediary elements between the external environment and the optical combiner. These polarizers act as selective mediators that allow real-world light to pass through while blocking excessive external light that would otherwise interfere with the image merging process. The polarizers are positioned and oriented to maintain the integrity of real-world light transmission while filtering out problematic external light sources.
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 effectively reduces external light interference, allowing for clear viewing of both virtual and real-world images by adjusting light intensity and polarization, enhancing the overall performance of the optical system.
Implementation Method 1
The optical combiner may have a reflector with a concave lens shape that redirects and focuses light from the display towards eye boxes in which a viewer's eyes are located
Implementation Method 2
The optical combiner may have a reflector with a concave lens shape that redirects and focuses light from the display towards eye boxes
Implementation Method 3
An optical component such as a circular polarizer may overlap the front-facing camera without overlapping the display on the front face of the cellular telephone to suppress stray light reflections from the display into the front-facing camera
Implementation Method 4
The reflector may be a reflective polarizer. The reflective polarizer and additional components such as layers of electrodes, additional polarizer layers, and a liquid crystal layer may be used in implementing a tunable tint layer
Implementation Method 5
The reflective polarizer and additional components such as layers of electrodes, additional polarizer layers, and a liquid crystal layer may be used in implementing a tunable tint layer
Data Source
AI summary
An optical system may include equipment with a housing that is configured to receive external equipment such as a cellular telephone. The external equipment may have a display mounted on a front face of the external equipment and may have additional components such as a front-facing camera. Communications circuitry in the equipment may support wired and wireless communications with the external equipment. An optical combiner in the equipment may be used to combine display image light emitted from pixels in the display with real-world image light received from external objects. The optical combiner may have a reflector with a concave lens shape that focuses light from the display towards eye boxes in which a viewer's eyes are located. The reflector may be a partial mirror or a reflective polarizer. The reflective polarizer and additional components may be used in implementing a tunable tint layer.