AR Glasses Display Assembly With Dual-Stiffness Drop Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Augmented-reality glasses are susceptible to damage from drops and external forces, particularly affecting display generation components like the display projector assembly and waveguide, which are fragile and expensive, and traditional assembly methods lead to poor optical alignment and user discomfort due to manufacturing tolerances and adhesive failure.
Innovation Solution
The optical stack is coupled to the frame via a first interface material with a specific stiffness, and the display projector assembly is coupled via a second interface material with a different stiffness, while alignment fiducials ensure precise alignment, using materials like high-density and low-density foam to absorb vibrations and maintain optical alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If traditional adhesive bonding is used to assemble components, then assembly simplicity is maintained, but alignment precision deteriorates due to adhesive weakening or failure over time
Solution Approach 1:
A mechanical alignment feature (such as a alignment pin, groove, or interlocking structure) is introduced as an intermediary element between the frame and the display generator assembly. This mechanical feature maintains precise optical alignment while allowing the adhesive to serve its original bonding function, thus resolving the contradiction between assembly simplicity and alignment precision.
2Reliability
If display generator components are made more robust to prevent damage, then durability improves, but device complexity increases due to additional protective structures
Solution Approach 1:
A flexible protective layer or cushioning element is positioned between the frame and the display generator assembly. This thin flexible structure absorbs impact forces during drops or shocks, protecting the fragile display generator components without adding significant structural complexity or bulk to the overall device.
3Ease of manufacture
If predefined compartments are made oversized to ensure component insertion, then ease of assembly improves, but alignment precision deteriorates due to manufacturing tolerances
Solution Approach 1:
The display generator assembly is pre-assembled with its optical components (waveguide, lenses, display element) precisely aligned relative to each other before being mounted in the frame. This preliminary assembly ensures optical precision is maintained during final installation, while the frame's predefined compartments can remain oversized for ease of assembly.
Data Source
AI summary
A display assembly for a pair of augmented-reality glasses is described. The display assembly includes an optical stack and a display projector assembly that is configured to present an augmented-reality experience via a portion of the optical stack at the augmented-reality glasses. The optical stack includes one or more lenses and a first interface material at a perimeter of the optical stack. The first interface material separates the optical stack from directly contacting a frame of the augmented-reality glasses. Additionally, a portion of the display projector assembly is suspended within a second interface material that is less stiff than the first interface material.