Surface-Stabilized IPS LCD Polymer Fibrils Decay Time
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current in-plane switching (IPS) LCDs suffer from slow decay times, limiting their ability to display moving images with high quality due to the lack of a polymer network to stabilize liquid crystal reorientation and improve switching speed.
Innovation Solution
A surface-stabilized IPS LCD is developed by incorporating polymer fibrils formed from a photopolymerizable liquid mixture between alignment layers on substrates with interdigitated electrodes, which align liquid crystals in a specific orientation, enhancing anchoring strength and response times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If conventional IPS LCD structure is used, then wide viewing angles and high optical contrast are achieved, but slow decay time limits dynamic response quality
Solution Approach 1:
The patent combines liquid crystal material with polymer material to form a composite system. The polymer network is formed in-situ within the liquid crystal layer through photopolymerization of monomers, creating a hybrid structure that provides both the optical properties of liquid crystals and the anchoring stability of polymers, thereby reducing decay time while maintaining viewing angle and contrast performance
Solution Approach 2:
The polymer network is not uniformly distributed but localized at specific regions where it provides enhanced anchoring strength for liquid crystal molecules. This local polymerization approach allows the liquid crystal molecules to be more firmly anchored at critical interfaces, accelerating their return to the initial state and reducing decay time without affecting the overall optical performance
2Speed
If polymer network is added to stabilize liquid crystal reorientation, then switching speed improves, but device complexity increases
Solution Approach 1:
The patent merges the liquid crystal layer and polymer network into a single integrated structure. The polymer monomers are mixed with the liquid crystal material before cell assembly, and photopolymerization occurs in-situ within the sealed cell, combining what would otherwise be separate manufacturing steps into one unified process, thereby avoiding additional device complexity
Solution Approach 2:
The liquid crystal mixture itself contains the polymer monomers and photoinitiators needed for network formation. Upon UV irradiation, the system self-organizes to form the polymer network structure autonomously without requiring external intervention or additional processing steps, simplifying the overall device fabrication process
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 introduction of surface-localized polymer fibrils significantly reduces rise and decay times, enabling IPS LCDs to display moving images with improved dynamic response and maintaining high light transmittance with and without an applied electric field.
Implementation Method 1
incorporating polymer fibrils formed from a photopolymerizable liquid mixture between alignment layers
Implementation Method 2
a voltage is applied across the electrodes of the IPS cell to form an electric field, referred to as a lateral electric field, which is applied between each end of the liquid crystal molecules
Data Source
AI summary
A surface-stabilized in-plane switching (SS-IPS) liquid crystal (LCD) cell includes a pair of spaced substrates that include alignment layers disposed thereon. The alignment layers are treated to define a first director orientation. Disposed between the alignment layers is a liquid crystal material that contains polymer fibrils that are disposed upon each of the alignment layers. The polymer fibrils serve to maintain the alignment of the liquid crystal molecules in the first director orientation when no voltage is applied to the LCD cell via interdigitated electrodes disposed upon the alignment layers, thus improving the dynamic response of the SS-IPS LCD cell.