Multi-material lamination for variable transmission optical uniformity

Solution Overview

Problem

Existing variable transmission elements with electro-optic devices face challenges in achieving optimal optical performance and durability due to limitations in materials and assembly processes, leading to potential optical distortions and reduced lifespan.

Innovation Solution

A variable transmission element is designed with a multi-material lamination structure, comprising substrates, lamination layers made from materials like TPU, PVB, and EVA, and an electro-optic device. The lamination layers are strategically positioned between the substrates and the electro-optic device, with a sealing material that does not include thermoplastic polyurethane (TPU), polyvinyl butyral (PVB), or ethylene vinyl acetate (EVA), to enhance optical uniformity and durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional single-material lamination is used, then manufacturing process is simple, but optical uniformity and durability are insufficient

Engineering Contradiction:

ImprovedurabilityVSAvoidlamination structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs a multi-material lamination structure comprising a first lamination layer (e.g., TPU) coupled to the second surface of the first substrate, a second lamination layer (e.g., PVB or EVA) coupled to the second substrate, and a seal formed of a sealing material extending along the perimeter of the substrates. This composite lamination approach enhances optical uniformity and durability by combining materials with complementary properties, resolving the contradiction between reliability improvement and structural complexity.

Inventive Principle:

Principle #40Composite materials

2Manufacturing precision

If traditional lamination materials are used, then manufacturing cost is low, but optical distortions occur

Engineering Contradiction:

Improveoptical uniformityVSAvoidlamination material complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies different lamination materials to different regions and functions within the assembly. The first lamination layer (e.g., TPU) provides specific optical and adhesive properties at the first substrate interface, while the second lamination layer (e.g., PVB or EVA) provides different properties at the second substrate interface. The seal material provides edge sealing and additional optical uniformity. This localized material differentiation achieves superior optical uniformity and eliminates distortions.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs a multi-material lamination structure comprising a first lamination layer (e.g., TPU) coupled to the second surface of the first substrate, a second lamination layer (e.g., PVB or EVA) coupled to the second substrate, and a seal formed of a sealing material extending along the perimeter of the substrates. This composite lamination approach enhances optical uniformity and durability by combining materials with complementary properties, resolving the contradiction between reliability improvement and structural complexity.

Inventive Principle:

Principle #40Composite materials

3Duration of action of stationary object

If simple sealing is used, then assembly process is simple, but durability and longevity are reduced

Engineering Contradiction:

ImprovelifespanVSAvoidassembly process complexity

Core Design Contradiction:

Duration of action of stationary objectVSEase of manufacture

Solution Approach 1:

The patent employs a multi-material lamination structure comprising a first lamination layer (e.g., TPU) coupled to the second surface of the first substrate, a second lamination layer (e.g., PVB or EVA) coupled to the second substrate, and a seal formed of a sealing material extending along the perimeter of the substrates. This composite lamination approach enhances optical uniformity and durability by combining materials with complementary properties, resolving the contradiction between reliability improvement and structural complexity.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS20250042136A1Multi-material lamination

Publication Date: 2025.02.06 GENTEX CORP

AI summary

A variable transmission element includes a first substrate that has a first surface and a second surface opposite the first surface. A second substrate includes a third surface and a fourth surface opposite the third surface. The first and second surfaces face each other and are disposed in a spaced apart relationship so as to define a space therebetween. A seal formed of a sealing material extends along a perimeter of the first and second substrates. A first lamination layer comprises a first lamination material that is different from the sealing material and the first lamination layer is coupled to the second surface. A second lamination layer comprises a second lamination material that is different from the sealing material and the second lamination layer is coupled to the second substrate. An electro-optic device is disposed between the first lamination layer and the second lamination layer.