Rectangular Waveguide Aperture Multipliers With Partial-Reflection Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical devices for two-dimensional optical aperture expansion face challenges in simplifying fabrication processes and reducing manufacturing costs while maintaining effective optical coupling and aperture expansion.
Innovation Solution
The use of a rectangular optical waveguide optically coupled with a thin slab-type optical waveguide, where the optical coupling-in configuration involves a partially reflective surface associated with the waveguide's lower face, and the waveguide regions have different optical characteristics, simplifying fabrication and reducing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a rectangular optical waveguide with internal partially reflective surfaces is used for optical coupling, then effective optical coupling and aperture expansion are achieved, but fabrication complexity and manufacturing costs increase
Solution Approach 1:
The patent extracts the partially reflective surface from the internal structure of the rectangular waveguide and relocates it to the interface between the rectangular waveguide and the thin slab waveguide. This extraction simplifies the rectangular waveguide structure by eliminating the need for internal partially reflective surfaces, thereby reducing fabrication complexity while maintaining optical coupling effectiveness through the interface-based reflective surface.
2Area of stationary object
If multiple waveguide structures with internal reflective surfaces are integrated, then aperture expansion is achieved, but device complexity and manufacturing costs increase
Solution Approach 1:
The patent merges the optical coupling function with the aperture expansion function by integrating the thin slab waveguide with the rectangular waveguide at their interface. The partially reflective surface at the interface serves dual purposes: enabling optical coupling between waveguides and facilitating aperture expansion through internal reflections in the thin slab waveguide, thereby reducing overall device complexity.
Solution Approach 2:
The patent applies different optical characteristics to different regions of the waveguide interface. The first region of the interface has a reflective coating to enable optical coupling, while the second region has different optical characteristics to facilitate aperture expansion. This local differentiation allows the system to achieve both functions with a relatively simple overall structure.
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 simplifies the manufacturing process and reduces costs while maintaining effective optical coupling and aperture expansion, enhancing image quality and efficiency.
Implementation Method 1
The rectangular waveguide has two pairs of parallel faces (that form a rectangular cross-section) and is configured to guide light by four-fold internal reflection at the two pairs of parallel faces
Implementation Method 2
a proportion of intensity of the image is reflected at the first set of internal surfaces so as to be coupled into the second waveguide
Implementation Method 3
The image light then advances by internal reflection at the major external faces of the second waveguide
Data Source
AI summary
An optical device includes a first waveguide, having parallel first and second faces and parallel third and fourth faces forming a rectangular cross-section, that guides light by four-fold internal reflection and is associated with a coupling-out configuration that couples light out of the first waveguide into a second waveguide. The first or second face is subdivided into first and second regions having different optical characteristics. The optical device also includes a coupling-in configuration having a surface that transmits light into the first waveguide. The surface is deployed in association with a portion of the third or fourth face adjoining the second region such that an edge associated with the surface trims an input collimated image in a first dimension, and a boundary between the first and second regions trims the input collimated image in a second dimension to produce a trimmed collimated image that advances by four-fold internal reflection.