Dummy Pixel TFT Layout for Uniform LCD Display Edges

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In liquid crystal display panels, the process environment differences between the display area and the peripheral area lead to uneven display, necessitating the use of dummy pixels, which can cause power consumption and affect display uniformity.

Innovation Solution

A display substrate design with dummy pixel units and dummy data lines in the peripheral area, featuring a thin film transistor with a disconnected source or drain electrode through an opening, maintaining a similar process environment and reducing load on gate lines, and incorporating electrode extension layers for improved signal stability and uniformity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If dummy pixels are designed around the display area to compensate for process environment differences, then display uniformity is improved, but power consumption increases and device complexity increases

Engineering Contradiction:
Improvedisplay uniformityVSAvoidpower consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The patent extracts the harmful electrical connection from the dummy pixel unit by introducing a first opening that disconnects the second electrode from the first electrode. This allows the dummy pixel unit to maintain the process environment benefit without consuming power through unnecessary electrical operations

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies different structural characteristics to different regions: the dummy pixel unit has a disconnected electrode structure (first opening) while effective pixel units maintain continuous electrodes. This local differentiation allows dummy pixels to serve their environmental compensation function without the power consumption of full operational structures

Inventive Principle:
Principle #3Local quality

2Manufacturing precision

If dummy pixels are designed around the display area to compensate for process environment differences, then display uniformity is improved, but device complexity increases

Engineering Contradiction:
Improvedisplay uniformityVSAvoiddevice complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The dummy pixel unit serves multiple functions: it maintains process environment consistency for surrounding effective pixels, provides structural symmetry for layout optimization, and eliminates power consumption through electrode disconnection. This multi-functionality reduces the need for separate compensation structures

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The second electrode is segmented into separate portions by the first opening, creating a disconnected structure. This segmentation allows the dummy pixel unit to be structurally similar to effective pixels while functionally distinct, simplifying the overall design by using a unified template approach

Inventive Principle:
Principle #1Segmentation

3Use of energy by moving object

If the second electrode is disconnected through an opening in the dummy pixel unit, then power consumption is reduced, but electrical connectivity is affected

Engineering Contradiction:
Improvepower consumptionVSAvoidelectrical connectivity
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The disconnection is applied locally only to dummy pixel units through the first opening, while effective pixel units maintain continuous electrode connections. This localized application ensures that electrical connectivity is preserved where needed (effective pixels) while eliminating power consumption where not needed (dummy pixels)

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The electrode structure is segmented into continuous portions (effective pixels) and disconnected portions (dummy pixels). The first opening creates a deliberate segmentation in dummy pixel units that separates the electrical connectivity function from the structural/environmental function

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP4067988B1Display substrate, display panel and electronic device
Publication Date: 2025.11.19 BOE TECHNOLOGY GROUP CO LTD
  • EP4067988B1 patent drawingFigure 1A
  • EP4067988B1 patent drawingFigure 1B~2
  • EP4067988B1 patent drawingFigure 3~4

AI summary

A display substrate is provided, including: a base substrate (10); a display area (20) and a peripheral area (30) surrounding the display area (20) on the base substrate, where a dummy pixel unit (31) and a dummy data line (32) are located in the peripheral area (30), the dummy pixel unit (31) includes a thin film transistor (40) including a first electrode (41) and a second electrode (42), the first electrode (41) is one of a source electrode and a drain electrode and is electrically connected to the dummy data line (32), and the second electrode (42) is another of the source electrode and the drain electrode and includes a first portion (421) and a second portion (422) separated by a first opening (43). A display panel including the display substrate and an electronic device including the display substrate or the display panel are further provided.