Pixel Circuit Light Sensor Integration for Touch and Display

Solution Overview

Problem

The integration of touch sensor and light sensing circuits in display panels increases the panel error rate and reduces the opening ratio and resolution, posing a challenge in achieving effective touch recognition and image display.

Innovation Solution

A pixel design incorporating a light sensor circuit with a switching transistor and a light sensing element that controls current supply to the organic light-emitting diode based on incident light, allowing for touch location and fingerprint sensing while maintaining the display's performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If touch sensor circuit and light sensing circuit are integrated into display panel, then touch recognition function is achieved, but panel error rate increases and opening ratio is reduced

Engineering Contradiction:

Improvetouch recognition functionVSAvoidpanel error rate

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent merges the touch sensor circuit and light sensing circuit into the pixel circuit by sharing common elements (transistors, signal lines, electrodes). The light sensing element uses the same pixel electrode structure, and the touch sensing shares the same transistor network, achieving functional integration without adding separate circuit blocks that would increase error rates.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements multi-functionality where the same circuit components serve multiple purposes: the pixel circuit handles both display driving and light sensing, the same transistor network is used for both touch sensing and pixel control, and the sensing electrode serves both touch detection and light intensity measurement functions.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If touch sensor circuit and light sensing circuit are integrated into display panel, then touch recognition function is achieved, but opening ratio is reduced

Engineering Contradiction:

Improvetouch recognition functionVSAvoidopening ratio

Core Design Contradiction:

Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The patent merges the touch sensor circuit and light sensing circuit into the pixel circuit by sharing common elements (transistors, signal lines, electrodes). The light sensing element uses the same pixel electrode structure, and the touch sensing shares the same transistor network, achieving functional integration without adding separate circuit blocks that would increase error rates.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements multi-functionality where the same circuit components serve multiple purposes: the pixel circuit handles both display driving and light sensing, the same transistor network is used for both touch sensing and pixel control, and the sensing electrode serves both touch detection and light intensity measurement functions.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If touch sensor circuit and light sensing circuit are integrated into display panel, then touch recognition function is achieved, but resolution is reduced

Engineering Contradiction:

Improvetouch recognition functionVSAvoidresolution

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent merges the touch sensor circuit and light sensing circuit into the pixel circuit by sharing common elements (transistors, signal lines, electrodes). The light sensing element uses the same pixel electrode structure, and the touch sensing shares the same transistor network, achieving functional integration without adding separate circuit blocks that would increase error rates.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements multi-functionality where the same circuit components serve multiple purposes: the pixel circuit handles both display driving and light sensing, the same transistor network is used for both touch sensing and pixel control, and the sensing electrode serves both touch detection and light intensity measurement functions.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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

This solution enhances touch recognition precision and maintains the display's resolution and opening ratio by integrating touch and light sensing functions within the pixel circuit, reducing the need for additional processes and manufacturing costs.

Implementation Method 1

a light sensing element coupled between the light sensor circuit switching transistor and a gate electrode of a driving transistor included in the pixel circuit... configured to provide a current output to the pixel circuit that is dependent on the light level incident on a light sensor element

Methodology Applied

Scientific EffectPhotoelectric Effect: Photoelectric Effect

Data Source

PatentEP3627295B1Pixel and display device including the same

Publication Date: 2023.04.26 SAMSUNG DISPLAY CO LTD

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AI summary

A pixel and a display device including the same. The pixel includes: a pixel circuit configured to control the amount of current to be supplied to an organic light-emitting diode in response to a data signal provided from a data line; and a light sensor circuit coupled between the data line and the pixel circuit and configured to control the amount of current to be supplied to the pixel circuit in response to incident light.