Display Touch-Driver Timing for Faster Coordinate Detection

Solution Overview

Problem

Display devices experience increased calculation time and power consumption for touch coordinate identification due to signal noise causing image flicker, particularly as the areas of the display and touch panels increase.

Innovation Solution

A display device with touch driving electrodes and a touch driver circuit that outputs driving signals sequentially in response to vertical synchronization signals, calculates elapsed time for touch input detection, and determines touch coordinates based on this time, using self-capacitive touch electrodes arranged in a matrix.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If touch coordinates are calculated using conventional methods, then touch input can be detected, but calculation time and power consumption increase

Engineering Contradiction:

Improvetouch coordinate identificationVSAvoidcalculation time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The system pre-calculates and stores timing information for driving signal output to each touch driving electrode in advance. When a touch is detected, the touch coordinates are determined by comparing the detection signal timing with the pre-stored timing data, eliminating the need for real-time calculation and reducing processing time.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent replaces complex coordinate calculation algorithms with a time-based measurement system. By measuring the time relationship between driving signal output and detection signal reception, the system determines touch coordinates through temporal measurement rather than mathematical computation, significantly reducing processing requirements.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If touch coordinates are calculated using conventional methods, then touch input can be detected, but power consumption increases

Engineering Contradiction:

Improvetouch coordinate identificationVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The system pre-calculates and stores timing information for driving signal output to each touch driving electrode in advance. When a touch is detected, the touch coordinates are determined by comparing the detection signal timing with the pre-stored timing data, eliminating the need for real-time calculation and reducing processing time.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent replaces complex coordinate calculation algorithms with a time-based measurement system. By measuring the time relationship between driving signal output and detection signal reception, the system determines touch coordinates through temporal measurement rather than mathematical computation, significantly reducing processing requirements.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Ease of operation

If touch panel driving signals are output, then touch input detection is enabled, but image flicker occurs on the display panel

Engineering Contradiction:

Improvetouch input detectionVSAvoidimage flicker

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The system outputs driving signals to touch driving electrodes in a periodic sequence synchronized with the display panel's vertical synchronization signal. This periodic timing ensures that touch detection operations are coordinated with the display refresh cycle, preventing interference that causes image flicker while maintaining touch detection functionality.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS20250271967A1Display device and method for driving the same

Publication Date: 2025.08.28 SAMSUNG DISPLAY CO LTD

AI summary

According to an embodiment, a display device may include a display panel comprising touch driving electrodes, and a touch driver circuit comprising a driving signal output unit configured to output driving signals supplied to the touch driving electrodes, and a touch control unit configured to control the driving signal output unit. The touch driver circuit is configured to sequentially output the driving signals in response to a vertical synchronization signal, receive a detection signal associated with a touch input on the display panel, calculate an elapsed time from a first time when the vertical synchronization signal is output until a second time when the detection signal is received, and determine touch coordinates of the touch input based on the elapsed time.