Holographic Optical Element Manufacturing via Preliminary Shaping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for manufacturing holographic optical elements (HOEs) with complex shapes, such as spherical, toric, or freeform designs, are not straightforward and lack efficient production processes, limiting their application in head-worn displays (HWDs).
Innovation Solution
A method involving the impingement of wavefronts on a material to cause a first structure change, followed by shaping to a modified shape, resulting in a second structure change, which combines to form an HOE with a structural attribute that redirects light based on the combined changes, allowing for the creation of HOEs with complex shapes suitable for HWDs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional HOE manufacturing methods are used, then flat or cylindrical HOEs can be manufactured using standard production processes, but complex shaped HOEs (spherical, toric, freeform) cannot be manufactured straightforwardly
Solution Approach 1:
The patent applies preliminary action by recording the holographic interference pattern on a flat substrate before shaping. The HOE is recorded in its unshaped state and then deformed into the final complex shape (spherical, toric, or freeform). This sequence allows standard manufacturing processes to create the holographic pattern, followed by a separate shaping step that achieves the complex geometry without compromising the recorded interference pattern.
Solution Approach 2:
The manufacturing process is segmented into distinct stages: (1) recording the holographic interference pattern on a flat substrate using standard processes, and (2) subsequently shaping the substrate into the complex final form. This segmentation allows each stage to be optimized independently, with standard processes handling the holographic recording and specialized processes handling the complex shaping.
2Adaptability or versatility
If HOE material is shaped to complex forms, then the HOE can be used with various HWD lens designs, but the manufacturing process becomes more difficult
Solution Approach 1:
The holographic pattern is recorded on the material while it remains in a simple, easily manufactured flat or cylindrical form. Only after the holographic recording is complete is the material shaped into the complex form required for specific HWD lens applications. This preliminary recording approach enables the same recorded HOE to be adapted to multiple lens designs through subsequent shaping.
Solution Approach 2:
By recording the holographic pattern on a universally compatible flat substrate that can subsequently be shaped into various forms (spherical, toric, freeform), the manufacturing process creates a universal HOE component that can serve multiple HWD lens applications. The single recorded pattern can be adapted to different optical requirements through geometric transformation.
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
Enables the efficient manufacturing of HOEs with complex shapes, enhancing their optical performance and versatility in HWDs by effectively redirecting light and combining virtual and real-world views.
Implementation Method 1
impinging at least one wavefront on a material having a first shape, the at least one wavefront to cause a first structure change in the material
Implementation Method 2
shaping the material to a second shape to cause a second structure change in the material
Implementation Method 3
HOE recording may be achieved, in one example, by recording an interference pattern of an wavefront object beam and a wavefront reference beam
Data Source
AI summary
Disclosed herein are devices and methods to provide a holographic optical element (HOE) having a modified shape and a structural attribute. At least one wavefront may be used to cause a first structure change in a material, used for the HOE, in a first shape. The material used for the HOE may be changed from the first shape to the modified shape to cause a second structure change in the material. The structural attribute in the material may be provided from a combination of the first structure change and the second structure change.