Nested Subpixel Structure for Electronic Paper Leakage Reduction

Solution Overview

Problem

Conventional electronic paper displays (EPDs) suffer from poor display quality due to pixel electrical leakage, especially under high temperature environments and when neighboring pixels have different polarities.

Innovation Solution

The display device incorporates a selection line, data line, and pixel units with subpixels, where each subpixel includes transistors and capacitors, with the second subpixel surrounding the first to improve electrical leakage, and increasing the number of transistors reduces leakage current.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional pixel structures are used, then device complexity is low, but electrical leakage occurs under high temperature and different polarity conditions

Engineering Contradiction:

Improveelectrical leakage resistanceVSAvoidpixel structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The pixel is divided into multiple subpixels (first subpixel and second subpixel), each with its own transistor and capacitor. This segmentation allows independent control and reduces electrical leakage by isolating the charge storage functions, thereby improving reliability without significantly increasing overall device complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second subpixel is disposed around the first subpixel, creating a nested structure where the first subpixel is surrounded by the second subpixel. This nested arrangement improves electrical leakage resistance by providing an additional protective layer while maintaining a compact pixel footprint.

Inventive Principle:

Principle #7Nested doll (Nesting)

2Reliability

If more transistors are added to reduce leakage current, then electrical leakage resistance improves, but device complexity increases

Engineering Contradiction:

Improveleakage current reductionVSAvoidtransistor count

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The pixel is divided into multiple subpixels (first subpixel and second subpixel), each with its own transistor and capacitor. This segmentation allows independent control and reduces electrical leakage by isolating the charge storage functions, thereby improving reliability without significantly increasing overall device complexity.

Inventive Principle:

Principle #1Segmentation

3Reliability

If second subpixel surrounds first subpixel, then electrical leakage resistance improves, but manufacturing precision requirements increase

Engineering Contradiction:

Improveelectrical leakage resistanceVSAvoidsubpixel alignment precision

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The second subpixel is disposed around the first subpixel, creating a nested structure where the first subpixel is surrounded by the second subpixel. This nested arrangement improves electrical leakage resistance by providing an additional protective layer while maintaining a compact pixel footprint.

Inventive Principle:

Principle #7Nested doll (Nesting)

Data Source

PatentUS10672323B2Display device having a plurality of subpixels having shared data line and gate line

Publication Date: 2020.06.02 E INK HLDG INC

AI summary

A display device includes a selection line, a data line and plural pixel units. Each of the pixel units includes a first subpixel and a second subpixel. The second subpixel is disposed around the first subpixel and surrounds the first subpixel. The first subpixel includes a first capacitor, and the second subpixel includes a second capacitor. The selection line is configured to provide a selection signal. The data line is configured to provide a data signal. The first subpixel is configured to transmit the data signal to the first capacitor according to the selection signal, and the second subpixel is configured to transmit the data signal to the second capacitor according to the selection signal.