Reflective Display Panel Spacer Geometry for Dark-State Light Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Reflective display panels suffer from light leakage in the dark state due to poor alignment of liquid crystal molecules caused by spacers and residual phase retardation, leading to suboptimal dark state performance.
Innovation Solution
The display panel design includes spacers with specific geometric properties, such as a top surface width to bottom surface width ratio greater than or equal to 0.91 and an included angle between the sidewall and bottom surface greater than 75 degrees, along with an inclined angle of liquid crystal molecules exceeding 9 degrees relative to the substrate surface, to minimize poor alignment areas and residual phase retardation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If spacers are provided on the reflective surfaces of display pixels, then the display panel can maintain structural integrity and cell gap, but the placement of the spacers causes poor arrangement of the liquid crystal molecules around it, resulting in light leakage in a dark state
Solution Approach 1:
The patent changes the geometric parameters of the spacer, specifically setting the top surface width to bottom surface width ratio to be greater than or equal to 0.91 and the included angle between sidewall and bottom surface to be greater than 75 degrees. These parameter modifications reduce the poor alignment area of liquid crystal molecules around the spacer, thereby reducing light leakage while maintaining structural integrity.
2Stability of the object's composition
If the residual phase retardation of the liquid crystal layer is present, then the liquid crystal layer can maintain its optical properties, but it causes light leakage in the dark state
Solution Approach 1:
The patent adjusts the inclination angle parameter of liquid crystal molecules, specifying that when the first electrode layer and second electrode layer are disabled, the inclined angle between the molecular long axis of each liquid crystal molecule and the substrate surface should be greater than 9 degrees. This parameter change reduces residual phase retardation and eliminates light leakage while maintaining optical properties.
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 design effectively reduces light leakage in the dark state by improving the alignment of liquid crystal molecules, enhancing the display panel's dark state performance.
Implementation Method 1
an inclined angle between a molecular long axis of each of the liquid crystal molecules and a substrate surface of the first substrate is greater than 9 degrees. An orthographic projection of the molecular long axis on the first substrate or the second substrate is parallel to an alignment direction of the first alignment layer or the second alignment layer
Data Source
AI summary
A display panel including a first substrate, a second substrate, a first alignment layer, a second alignment layer, a liquid crystal layer, a first electrode layer and a second electrode layer is provided. The first alignment layer and the second alignment layer are respectively disposed on the first substrate and the second substrate. The first electrode layer and the second electrode layer are used to drive a plurality of liquid crystal molecules of the liquid crystal layer. While the first electrode layer and the second electrode layer are deactivated, a molecular long axis of each liquid crystal molecule against a substrate surface of the first substrate at an inclined angle is greater than 9 degrees. An orthographic projection of the molecular long axis on the first substrate or the second substrate is parallel to an alignment direction of the first alignment layer or the second alignment layer.