TIR Display Particle Segmentation for Uniform Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Beaded outward sheet TIR displays face issues with non-uniform distribution of TIR-frustrating particles, settling of particles over time, and non-uniformity of the electric field, leading to deterioration in image quality and performance.
Innovation Solution
The use of tethered particles, varying electrophoretic mobilities, and micro-cells or microcapsules to ensure uniform distribution and prevent settling, along with conforming backplane electrodes to maintain a uniform electric field, addresses these challenges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If particles are suspended in the electro-active medium to frustrate TIR, then the display can achieve high brightness and wide viewing angle, but the particles become non-uniformly distributed and settle over time, deteriorating image quality
Solution Approach 1:
The display is divided into multiple micro-cells that are physically separated by walls. Each micro-cell contains a subset of the electrophoretic particles, confining them to smaller regions. This segmentation prevents particles from migrating laterally across the entire display area and settling uniformly, thereby maintaining consistent particle distribution and image quality over time while preserving the TIR-frustration mechanism for high brightness.
Solution Approach 2:
The patent modifies the electrophoretic properties of the particles by adjusting their charge, size, or composition to change their mobility characteristics. This parameter change ensures that particles respond appropriately to the electric field for TIR frustration while having reduced tendency to settle under gravity, thus maintaining both brightness performance and distribution stability.
2Ease of manufacture
If particles are allowed to migrate laterally in the electro-active medium, then the display can be manufactured with simpler structures, but the particle migration causes non-uniformity in the electric field and image deterioration
Solution Approach 1:
The display structure is segmented into micro-cells using walls that divide the electro-active medium into smaller compartments. This segmentation is relatively simple to manufacture and effectively prevents lateral particle migration, maintaining electric field uniformity across each micro-cell while avoiding complex overall structures.
Solution Approach 2:
The walls are strategically positioned at specific locations within the display to create micro-cells. This local modification approach maintains simplicity in the overall structure while locally addressing the particle migration issue, ensuring electric field uniformity where it matters most for image quality without requiring complex global restructuring.
3Speed
If the electric field is made non-uniform to allow particle movement, then the display can achieve faster switching speeds, but the non-uniformity leads to inconsistent TIR frustration and reduced image quality
Solution Approach 1:
The display is segmented into micro-cells, and each micro-cell is independently controlled by its own electrode configuration. This allows the electric field to be optimized for fast switching within each small region while the segmentation prevents field non-uniformity from affecting the entire display, maintaining consistent TIR frustration across all regions.
Solution Approach 2:
The patent employs dynamic electric field control within each micro-cell, allowing the field strength and distribution to change rapidly for fast switching. The confined geometry of micro-cells ensures that these dynamic changes remain localized and do not create problematic non-uniformities across the full display area, preserving image quality.
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
These solutions enhance the uniformity of particle distribution, prevent lateral migration, and maintain a consistent electric field, thereby improving the contrast ratio and long-term performance of the display.
Implementation Method 1
Suspended in the liquid medium are a plurality of electrophoretically mobile particles
Implementation Method 2
a high refractive index (e.g. η1> ∼1.90) transparent spherical or approximately spherical beads
Implementation Method 3
frustrated total internal reflection (TIR) modulated display
Data Source
AI summary
The disclosed embodiments relate to lateral migration of particles in a totally internally reflective displays. In certain embodiments, the reflective image displays include partial and full walls to form partitions within the display. The walls mitigate diffusion and lateral migration or drift of electrophoretically mobile particles due to lateral electric fields at adjacent pixels. This improves image quality, bistability and long-term display performance.