AR Waveguide Stack Sealing to Reduce Heat and Condensation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current Head-Mounted Displays (HMDs) face issues such as high cost, heating problems, and condensation around waveguides, which hinder their effectiveness in providing augmented reality experiences.

Innovation Solution

An augmented reality eyewear display system with a frame, projection display device, waveguide stack module, and hinge system, incorporating features like touchpad, microphone, and ambient light sensor to enhance user interaction and adapt to environmental conditions, while using materials like komoto and carbonfeather for light absorption and gaskets for environmental sealing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional HMDs use waveguides for optical imaging, then virtual images can be superimposed over real-world images, but heating issues and condensation around waveguides occur

Engineering Contradiction:
Improveeffectiveness of HMDVSAvoidheating around waveguides
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The patent divides the waveguide system into a stack of multiple waveguides (first waveguide, second waveguide, etc.) with distinct functions. The first waveguide receives light from the display device, while subsequent waveguides progressively redirect light toward the user's eye. This segmentation distributes thermal load across multiple components and enables better heat management through strategic placement of heat dissipation features.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces intermediate components between the display device and the user's eye, including multiple waveguides with diffractive optics, beam combiners, and heat dissipation structures. These intermediary elements facilitate light transmission while providing pathways for heat dissipation, preventing direct thermal contact between the display device and sensitive optical components.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If conventional HMDs use waveguides for optical imaging, then virtual images can be superimposed over real-world images, but condensation develops around waveguides

Engineering Contradiction:
Improveeffectiveness of HMDVSAvoidcondensation around waveguides
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The waveguide system is segmented into multiple discrete waveguides with specific functional divisions. This segmentation allows for targeted environmental control, where each waveguide can be independently managed regarding thermal and humidity conditions, preventing condensation formation through controlled micro-environments around each optical element.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent creates controlled environments around the waveguide stack, effectively establishing inert atmospheric zones that prevent moisture condensation. This is achieved through thermal management structures and sealing mechanisms that maintain stable temperature and humidity conditions around the optical paths, eliminating the harmful condensation effect.

Inventive Principle:
Principle #39Inert atmosphere (Inert environment)

3Ease of manufacture

If conventional HMDs are designed with basic components, then manufacturing cost is reduced, but user interaction capabilities and environmental adaptation are limited

Engineering Contradiction:
Improvecost of HMDVSAvoiduser interaction and environmental adaptation
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent integrates multiple functions into a unified waveguide stack architecture. The same stack of waveguides simultaneously performs optical image transmission, thermal management, and environmental sealing. Additional sensors (ambient light sensors, touch sensors) are integrated into the existing structure, allowing cost-effective multi-functionality without requiring separate dedicated components for each function.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges previously separate functions into integrated components. The waveguide stack combines light guidance, heat dissipation, and environmental protection in a single structure. Touchpad and sensor interfaces are merged into the frame structure, reducing component count and manufacturing complexity while maintaining advanced user interaction and environmental adaptation capabilities.

Inventive Principle:
Principle #5Merging (Combining)

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

The system provides cost-effective, efficient, and reliable augmented reality experiences by reducing heating and condensation issues, enhancing user interaction, and adapting to lighting conditions, thereby improving safety and efficiency.

Implementation Method 1

an in-coupling diffractive optic formed along the at least one waveguide stack module for diffracting the image-bearing light beams from the projection display device into the at least one waveguide stack module

Methodology Applied
Scientific EffectDiffraction: Diffraction

Implementation Method 2

for propagating the image-bearing light beams along the length of the at least one waveguide stack module

Methodology Applied
Scientific EffectTotal Internal Reflection: Total Internal Reflection

Implementation Method 3

an out-coupling diffractive optic spaced apart from the in-coupling diffractive optic along the length of the at least one waveguide stack module for diffracting the image-bearing light beams from the at least one waveguide stack module in an angularly decoded form

Methodology Applied
Scientific EffectDiffraction: Diffraction

Implementation Method 4

The waveguide stack module may include a blackening material to absorb excess light from the projection display device that goes past the in-coupling diffractive optic

Methodology Applied
Scientific EffectAbsorption (EM radiation): Absorption (EM radiation)

Data Source

PatentEP3701316B1Augmented reality display system
Publication Date: 2026.03.04 VUZIX CORP
  • EP3701316B1 patent drawingFigure 1
  • EP3701316B1 patent drawingFigure 2
  • EP3701316B1 patent drawingFigure 3

AI summary

A personal display device for displaying virtual images to a wearer. The personal display device includes a frame having a right temple section, a left temple section, a right rear section, a left rear section, a right eye see-through section, and a left eye see-through section; a projection display device connected to the frame for projecting an image to the wearer; at least one waveguide stack module connected to the frame for propagating image-bearing light beams along a length of the at least one waveguide stack module, the at least one waveguide stack module being configured to receive the image from the projection display device and detected touch motions of the wearer sensed by the touchpad including sensing directions of the touch motions of the wearer.