Optical Laminate Structure for Thin Smart Windows With Higher Transmittance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional variable transmittance optical stacks require a separate substrate for forming a conductive layer, leading to increased manufacturing complexity, cost, and thickness, as well as reduced transmittance due to retardation effects.
Innovation Solution
A variable transmittance optical stack is designed without a separate substrate for the conductive layer, where the conductive layer is directly formed on the polarizing plate, simplifying the manufacturing process, reducing thickness, and improving transmittance by adjusting the wavelength dispersion characteristics of the polarizing rotation and retardation layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a separate substrate is used to form the conductive layer, then the structural stability is improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent combines the substrate and conductive layer into a single integrated structure where the transparent substrate itself serves as the base for the conductive layer. This eliminates the need for a separate substrate to form the conductive layer, thereby reducing device complexity and manufacturing steps while maintaining structural stability through the integrated design.
Solution Approach 2:
The transparent substrate is designed to serve multiple functions: it provides structural support, serves as the base for the conductive layer, and contributes to the overall optical properties. This multi-functionality reduces the need for additional components and simplifies the manufacturing process.
2Reliability
If a separate substrate is used to form the conductive layer, then the conductive layer can be properly formed, but the thickness of the laminate increases
Solution Approach 1:
By merging the substrate and conductive layer formation into a single integrated process, the patent eliminates the additional thickness that would result from using a separate substrate. The conductive layer is formed directly on the transparent substrate, reducing the overall laminate thickness while ensuring proper conductive layer formation.
3Reliability
If a separate substrate is used to form the conductive layer, then the conductive layer can be properly supported, but the transmittance decreases due to retardation
Solution Approach 1:
The integrated design where the conductive layer is formed directly on the transparent substrate eliminates additional interfaces and layers that cause retardation effects. This improves light transmittance while the transparent substrate provides adequate support for the conductive layer.
Solution Approach 2:
The patent optimizes the local properties of the transparent substrate at the interface with the conductive layer to minimize retardation effects. By carefully controlling the material properties and interface quality, the substrate provides sufficient support for the conductive layer while maintaining high light transmittance.
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 solution results in a simplified manufacturing process, reduced thickness, improved transmittance in the light transmissive mode, and enhanced light blocking performance in the light blocking mode, specifically reducing side light leakage.
Implementation Method 1
a variable transmittance optical stack capable of changing the transmittance of light when a voltage is applied has been developed
Implementation Method 2
a first polarizing plate including a first polarizer and a polarizing rotation layer
Implementation Method 3
a second polarizing plate including a second polarizer and a retardation layer
Data Source
AI summary
The present invention relates to a transmittance-variable optical laminate, a method for manufacturing same, a smart window comprising same, and a vehicle and building window or door employing same, the optical laminate comprising: a first polarizing plate including a first polarizer and a polarization rotation layer; a first transparent conductive layer formed on one surface of the first polarizing plate; a second polarizing plate including a second polarizer and a retardation layer, and facing the first polarizing plate; a second transparent conductive layer formed on one surface of the second polarizing plate, and facing the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer.