Electrophoretic Display Sheet with Low-Resistance Grid Electrode
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrophoretic displays face a trade-off between achieving high white light reflectance and maintaining stable display properties due to the limitations in light transmittance and electrical resistance of the light-transmissive electrodes, leading to uneven voltages and reduced image quality.
Innovation Solution
Incorporating a conductive portion with lower electrical resistance, formed by wires arranged in a grid or honeycomb pattern, which overlaps with the display layer, to reduce voltage drops and prevent bubbles, while maintaining a thin electrode structure for higher light transmittance and brighter images.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the thickness of the light-transmissive electrode is reduced to increase light transmittance, then the light transmittance is improved, but the electrical resistance increases causing voltage drops and deteriorated display properties
Solution Approach 1:
The electrode layer is constructed as a composite structure combining a light-transmissive membrane electrode with a conductive portion made of lower-resistance material (such as metal wires or conductive traces). This composite design allows the thin electrode to maintain both high light transmittance and low electrical resistance, resolving the contradiction between optical performance and electrical stability.
2Illumination intensity
If the thickness of the light-transmissive electrode is reduced to increase light transmittance, then the light transmittance is improved, but voltage drops occur due to increased electrical resistance
Solution Approach 1:
The conductive portion acts as an intermediary element between the power supply and the light-transmissive electrode. It provides a low-resistance current path that compensates for the high resistance of the thin electrode, ensuring stable voltage delivery without requiring increased power consumption.
3Illumination intensity
If the light-transmissive electrode is made thinner to achieve higher light transmittance, then image brightness is improved, but the electrode cannot maintain desired electric field intensity
Solution Approach 1:
The composite electrode structure combines the optical advantages of a thin light-transmissive membrane with the electrical advantages of a low-resistance conductive portion, enabling the system to achieve both high image brightness and sufficient electric field intensity for stable microcapsule operation.
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 enables the display of more luminous images while maintaining stable display properties by reducing voltage drops and preventing bubbles, thus enhancing the overall image quality and durability of the display.
Implementation Method 1
the conductive portion has a plurality of wires that are provided so as to overlap with the display layer in plan view of the display layer, the conductive portion being formed of a material with a lower electrical resistance than that of a material forming the electrode
Implementation Method 2
Electrophoretic displays utilizing the electrophoresis of particles are known as components that have been employed for the image display section of electronic paper
Data Source
AI summary
A display sheet includes a light-transmissive substrate, an electrode layer formed on a surface of the substrate, and a display layer that is provided on a surface of the electrode layer opposite the substrate and has a plurality of reservoirs containing at least one kind of electrophoretic particles. The electrode layer has a light-transmissive membrane electrode and a conductive portion electrically connected with the electrode. The conductive portion has a plurality of wires that are provided so as to overlap with the display layer in plan view of the display layer. The conductive portion is formed of a material with a lower electrical resistance than that of a material forming the electrode.