Foldable Display Polarization Plate for Distortion-Free Hinge Areas
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Foldable displays suffer from image distortion at the folding portion due to deformation of polarizing plates over time, which is a common issue in flexible and foldable displays.
Innovation Solution
A polarizing plate for foldable displays comprising a polyester film with specific refractive indices and density, and optionally a retardation layer, which is produced by transferring or applying a polarizer and retardation layer onto the film, ensuring minimal deformation and image distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a conventional polarizing plate is used in a foldable display, then the display can be folded, but the polarizing plate deforms over time causing image distortion at the folding portion
Solution Approach 1:
The patent changes the physical parameters of the polarizing plate by controlling the refractive index of the polyester film substrate and adjusting the thickness of the polarizing layer to 12 μm or less. These parameter modifications enable the polarizing plate to withstand repeated folding without deformation, maintaining image quality while preserving foldability.
Solution Approach 2:
The patent employs a composite structure consisting of a polyester film substrate with specific refractive index properties and a thin polarizing layer. This composite material design provides both the flexibility needed for folding and the stability required to prevent image distortion over time.
2Strength
If the polarizer thickness is reduced to improve flexibility, then the foldable display can be folded more easily, but the polarization performance may be compromised
Solution Approach 1:
The patent optimizes the thickness parameter of the polarizing layer to 12 μm or less, which provides sufficient flexibility for folding while maintaining adequate polarization performance through the synergistic effect of the thin polarizing layer and the optically controlled polyester film substrate.
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 provides a polarizing plate that maintains image quality without distortion even after repeated folding, suitable for foldable displays.
Implementation Method 1
a refractive index in a bending direction is from 1.590 to 1.620; a refractive index in a folding portion direction is from 1.670 to 1.700; a refractive index in a thickness direction is 1.520 or less
Data Source
AI summary
The present invention provides a polarizing plate for a foldable display free of a risk of causing distortion in an image displayed at a folding portion thereof after being repeatedly folded. The polarizing plate for a foldable display includes: a polarizer; and a polarizer protective film formed of a polyester film laminated on at least one surface of the polarizer, wherein the polyester film satisfies the following conditions: (1) a refractive index in a bending direction is from 1.590 to 1.620; (2) a refractive index in a folding portion direction is from 1.670 to 1.700; (3) a refractive index in a thickness direction is 1.520 or less; and (4) a density is 1.380 g/cm3 or more, wherein the bending direction refers to a direction orthogonal to a folding portion of the polyester film at a time when the polyester film is folded.