Scanning Mirror Display Devices for Mixed Reality
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electronic devices designed for virtual and mixed reality, such as head-mounted devices, often become overly complex and uncomfortable due to their bulkiness, which can be mitigated by optimizing the display system to provide clear, unobstructed views of both virtual and real-world objects.
Innovation Solution
The display system incorporates a light source, a waveguide, a phase grating that diffracts light, and a scanning mirror system, with control circuitry adjusting light intensity and color dynamically, allowing the user to view virtual images overlaid on real-world objects through an output coupler while maintaining transparency for real-world visibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a traditional display system is used in head-mounted devices, then virtual reality content can be displayed, but the device becomes bulky and uncomfortable to wear
Solution Approach 1:
The patent embeds the scanning mirror system within the waveguide structure itself, nesting multiple functional components (light source, phase grating, mirror, output coupler) in a compact integrated arrangement that fits within the constraints of head-mounted device form factors
Solution Approach 2:
The patent uses a two-dimensional scanning mirror system that deflects light in both horizontal and vertical dimensions, enabling compact folding of the optical path within the waveguide, thereby reducing the overall device volume while maintaining display functionality
2Volume of stationary object
If a waveguide with phase grating and scanning mirror is used, then device bulkiness is reduced, but the system becomes overly complex
Solution Approach 1:
The waveguide structure serves multiple functions simultaneously: it acts as the light guide, contains the phase grating for diffraction, houses the scanning mirror system, and functions as the output interface through the transparent waveguide face, thereby reducing the number of separate components needed
Solution Approach 2:
The patent combines the light source, phase grating, scanning mirror, and output coupler into an integrated waveguide-based display system where components are merged into a single compact unit, simplifying the overall structure while maintaining functionality
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 enhances user comfort by providing a clear, mixed reality experience without obstructing real-world views, improving the usability and effectiveness of virtual and mixed reality devices.
Implementation Method 1
A phase grating may diffract the light. Diffracted light may pass through an angled edge of the waveguide to a mirror element
Implementation Method 2
The diffracted light may be incident on a scanning mirror. The scanning mirror may reflect the light back toward the waveguide. The waveguide may guide the light to an output coupler
Implementation Method 3
The output coupler may extract the light from the waveguide and direct the light toward an eye of a user
Implementation Method 4
A wave plate may be used to change the polarization state of light reflected from the mirror element relative to incoming diffracted light from the phase grating
Data Source
AI summary
An electronic device may have a light source such as a laser light source. The light source may emit light into a waveguide. A phase grating may diffract the light that is emitted into the waveguide to produce diffracted light. The diffracted light may be oriented parallel to a surface normal of an angled edge of the waveguide and parallel to a surface normal of a microelectromechanical systems mirror element in a two-dimensional scanning microelectromechanical systems mirror that is coupled to the edge of the waveguide. A wave plate may be interposed between the mirror and the edge of the waveguide to change the polarization state of light reflected from the mirror element relative to incoming diffracted light from the phase grating. The phase grating may be configured so that the reflected light is not diffracted by the phase grating.