Wire Grid Polarizer Non-Planar Middle Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing wire grid polarizers in liquid crystal displays face challenges with reduced light efficiency due to the absorption type polarizing plates and high manufacturing costs for large-area polarizers, as well as deterioration in polarization efficiency caused by thick planarization layers.
Innovation Solution
A wire grid polarizer structure is developed with a non-planar middle layer that reduces thickness, comprising multiple wire grid layers with alternating thicknesses and materials, including inorganic and organic components, to minimize polarization efficiency loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a thick planarization layer is used between wire grid layers, then the surface flatness is improved, but the polarization efficiency deteriorates
Solution Approach 1:
The middle layer is designed with non-uniform thickness, being thinner in regions where wire grid lines are present and thicker in regions where wire grid lines are absent. This local variation in thickness allows the layer to provide surface flatness where needed while minimizing polarization efficiency loss in critical regions.
Solution Approach 2:
Instead of using a uniformly thick planarization layer, the patent introduces a dimensional variation in the middle layer thickness, creating a profile that transitions between different thickness regions. This allows optimization of both surface flatness and polarization efficiency by distributing the flatness function spatially.
2Area of stationary object
If a large area wire grid polarizer is manufactured, then the display size is increased, but the manufacturing cost increases due to difficulty in making large area nano-imprint molds
Solution Approach 1:
The wire grid polarizer is divided into multiple wire grid layers separated by middle layers. This segmentation allows the use of smaller, more manageable nano-imprint molds for each layer rather than requiring a single large-area mold, thereby reducing manufacturing difficulty and cost while achieving the desired large display area.
Solution Approach 2:
The patent transitions from a single-layer wire grid structure to a multi-layer structure with intermediate middle layers. This dimensional change in structure enables the use of smaller molds for each layer, making large-area polarizer manufacturing more feasible and cost-effective.
3Reliability
If absorption type polarizing plates are used, then the polarization control is achieved, but the light efficiency is reduced
Solution Approach 1:
The patent replaces the absorption-type polarizing plate mechanism with a wire grid polarizer that uses constructive and destructive interference of light waves. This substitution eliminates the need for light absorption, thereby maintaining polarization control while significantly improving light efficiency.
Solution Approach 2:
The wire grid polarizer utilizes optical interference effects to selectively transmit and block polarized light, similar to how color filters work. By controlling the interference patterns through the wire grid structure, the polarizer achieves polarization control without absorbing light, thus maintaining high light efficiency.
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
This configuration enhances light efficiency and reduces manufacturing costs by maintaining high polarization efficiency even in large-area displays, preventing deterioration associated with thick planarization layers.
Implementation Method 1
a wire grid polarizer has been proposed... to control polarization of incident light
Implementation Method 2
the polarization efficiency may deteriorate or decrease due to the thickness of the planarization layer
Data Source
AI summary
A display device includes a substrate and a wire grid polarizer disposed on the substrate. The wire grid polarizer includes a first wire grid layer, a first middle layer, and a second wire grid layer. The first wire grid layer includes a plurality of first wire grid lines separated from each other. The first middle layer is disposed on the first wire grid layer. The first middle layer includes a first portion having a first middle layer thickness and a second portion having a second middle layer thickness thinner than the first middle layer thickness. The second middle layer thickness is thinner than a thickness of each first wire grid line. The second wire grid layer is disposed on the first middle layer and includes a plurality of second wire grid lines separated from each other. The second wire grid lines overlap the second portion of the first middle layer.