Anti-Reflective Coating for ON-CELL Touch Screen Edges

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Solution Overview

Problem

The visibility of transparent conductive patterns in ON-CELL touch screens under ambient light affects the display effect, as they cause abnormal reflection and differing reflectivity on the screen surface.

Innovation Solution

An anti-reflective pattern, made of a black material, is applied to cover the edges and/or regions between transparent conductive patterns, reducing visibility by minimizing light reflectivity and being sized to be invisible to the human eye, typically ranging from 2µm to 20µm in width.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If transparent conductive patterns are used in the touch structure layer, then the touch detection function is achieved, but the patterns become visible under ambient light causing abnormal reflection

Engineering Contradiction:
Improvetouch detection functionVSAvoidvisibility and abnormal reflection
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies different properties to different parts of the transparent conductive pattern by adding an anti-reflective coating specifically to the edge portions (first and second edges) of the transparent conductive patterns, while leaving the center regions transparent. This local differentiation reduces reflection at the edges where visibility occurs without affecting the touch detection functionality in the center regions.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent introduces an anti-reflective coating as an intermediary substance applied to the edge portions of the transparent conductive patterns. This coating layer acts as a mediator that reduces the reflection of ambient light at the edges, thereby reducing visibility without interfering with the electrical functionality of the transparent conductive patterns.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the touch structure layer is placed close to the human eyes (ON-CELL configuration), then the touch sensitivity is improved, but the transparent conductive patterns become more visible under ambient light

Engineering Contradiction:
Improvetouch sensitivityVSAvoidvisibility under ambient light
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent applies the anti-reflective coating selectively to the edge portions of the transparent conductive patterns in the ON-CELL configuration, making only the problematic edge regions less reflective while maintaining the transparency and touch sensitivity of the center regions. This local treatment allows the ON-CELL configuration to maintain its touch sensitivity advantage while reducing visibility issues.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The anti-reflective coating changes the optical properties of the edge portions of the transparent conductive patterns by reducing their reflectivity. This optical property change makes the edge portions less visible under ambient light while maintaining the overall transparency of the touch structure layer for touch detection functionality.

Inventive Principle:
Principle #32Color changes

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

Significantly reduces the visibility of transparent conductive patterns, enhancing the display effect by minimizing abnormal reflections and making the patterns imperceptible under ambient light.

Implementation Method 1

The visibility of transparent conductive patterns in ON-CELL touch screens under ambient light affects the display effect, as they cause abnormal reflection and differing reflectivity on the screen surface

Methodology Applied
Scientific EffectLight reflection: Reflection

Data Source

PatentEP2784637B1Touch screen, touch display panel and touch display device
Publication Date: 2019.04.03 SHANGHAI TIANMA MICRO ELECTRONICS CO LTD
  • EP2784637B1 patent drawingFigure 1~2
  • EP2784637B1 patent drawingFigure 3~4
  • EP2784637B1 patent drawingFigure 5~6

AI summary

According to embodiments of the present invention, it is provided a touch screen, an ON-CELL touch display panel and a touch display device. The touch screen includes: a substrate; a touch structure layer disposed on the substrate, the touch structure layer including multiple transparent conductive patterns; and an anti-reflective pattern covering at least the edges of the transparent conductive patterns. In the touch screen, the touch display panel and the touch display device provided by the embodiments of the present invention, the anti-reflective pattern is used to cover the edges of the transparent conductive patterns and/or a region between multiple transparent conductive patterns in the touch screen, thus significantly reducing the visibility of the transparent conductive pattern in the touch screen under the ambient light, and improving the display effect.