Touch Sensor Corner Sensitivity via Single-Layer Sensing Lines

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Touch sensors experience reduced sensing sensitivity due to short defects in specific areas, particularly at corners, caused by differences in electrode pattern density between sensing and non-sensing areas.

Innovation Solution

The touch sensor is designed with at least one sensing line adjacent to a bridge pattern at the corner portion of the sensing area, formed as a single metal layer different from the bridge pattern, to maintain similar electrode pattern density across the sensing area.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If sensing lines are formed in the non-sensing area with standard multilayer structure, then electrical connectivity is achieved, but electrode pattern density becomes uneven causing short defects in bridge patterns

Engineering Contradiction:
Improvesensing sensitivityVSAvoidbridge pattern width uniformity
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by forming at least one sensing line adjacent to the bridge pattern using a single metal layer instead of the standard multilayer structure. This local modification equalizes the electrode pattern density between the sensing area and non-sensing area, preventing short defects in the bridge pattern while maintaining electrical connectivity of the sensing lines

Inventive Principle:
Principle #3Local quality

2Reliability

If electrode pattern density is increased in the non-sensing area to match the sensing area, then sensing sensitivity is improved, but the complexity of the sensing line structure increases

Engineering Contradiction:
Improvesensing sensitivityVSAvoidsensing line structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Rather than uniformly increasing electrode density throughout the non-sensing area, the patent applies local quality by modifying only the specific sensing line adjacent to the bridge pattern. This sensing line is formed with a single metal layer while other sensing lines can maintain the standard multilayer structure, thus improving sensing sensitivity without unnecessarily increasing overall device complexity

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3764205B1Touch sensor and display device having the same
Publication Date: 2025.02.12 SAMSUNG DISPLAY CO LTD
  • EP3764205B1 patent drawingFigure 1A~1B
  • EP3764205B1 patent drawingFigure 2
  • EP3764205B1 patent drawingFigure 3A

AI summary

A touch sensor including a base layer including a sensing area and a non-sensing area, first and second sensor patterns disposed in the sensing area and arranged along first and second directions, respectively, first bridge patterns arranged along the first direction, second bridge patterns arranged along the second direction, and sensing lines disposed in the non-sensing area and connected to each of the first and second sensor patterns, in which each of the sensing lines includes a first metal layer and a second metal layer with an insulating layer interposed therebetween, each of the sensing lines has a first portion and a second portion, the second portion corresponding to at least one of the first bridge patterns disposed at a corner portion of the sensing area, and the second portion of at least one of the sensing lines has a single layer structure including only the second metal layer.