Segmented Display Scan Driving Circuit for Brightness and Power Control

Solution Overview

Problem

Existing display devices face challenges in maintaining consistent display quality and reducing power consumption, particularly when operating in different modes such as video and still image display, due to variations in driving frequencies and scan signal activation states.

Innovation Solution

The display device incorporates a scan driving circuit with stages that include masking circuits, driving circuits, and auxiliary circuits, utilizing transistors and capacitors to synchronize and separate scan signal outputs, allowing for different driving frequencies in distinct display regions, thereby stabilizing scan signal voltages and reducing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single scan driving circuit outputs scan signals to all stages with the same period every frame, then the circuit structure is simple, but brightness variations occur and display quality deteriorates

Engineering Contradiction:

Improvescan driving circuit structureVSAvoiddisplay quality

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The scan driving circuit is divided into multiple independent stages (first stage, second stage, third stage), each capable of operating at different driving frequencies. Each stage has its own masking circuit and auxiliary transistor, allowing independent control of scan signal output to different display regions, thereby eliminating brightness variations while maintaining reasonable circuit complexity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent implements dynamic frequency adjustment by allowing different stages to operate at different driving frequencies based on display mode (video mode vs. still image mode). The auxiliary transistors and masking circuits dynamically control the scan signal output frequency for each stage, enabling the system to adapt to different display requirements and maintain optimal display quality

Inventive Principle:

Principle #15Dynamics

2Manufacturing precision

If the scan driving circuit operates at high driving frequency for video mode, then display quality is improved, but power consumption increases

Engineering Contradiction:

Improvedisplay qualityVSAvoidpower consumption

Core Design Contradiction:

Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The patent implements dynamic frequency adjustment by allowing different stages to operate at different driving frequencies based on display mode (video mode vs. still image mode). The auxiliary transistors and masking circuits dynamically control the scan signal output frequency for each stage, enabling the system to adapt to different display requirements and maintain optimal display quality

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

Different display regions (first display region and second display region) are allowed to operate at different driving frequencies simultaneously. The second stage can output scan signals at different frequencies to different regions, enabling local optimization where only necessary regions operate at high frequency, thereby reducing overall power consumption while maintaining display quality

Inventive Principle:

Principle #3Local quality

3Manufacturing precision

If masking circuits and auxiliary transistors are added to separate scan signal outputs, then brightness variations are reduced, but device complexity increases

Engineering Contradiction:

Improvedisplay qualityVSAvoidcircuit structure

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The scan driving circuit is divided into multiple independent stages (first stage, second stage, third stage), each capable of operating at different driving frequencies. Each stage has its own masking circuit and auxiliary transistor, allowing independent control of scan signal output to different display regions, thereby eliminating brightness variations while maintaining reasonable circuit complexity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second stage is designed with multi-functionality to output scan signals at different driving frequencies to different display regions simultaneously. The masking circuit and auxiliary transistor in each stage serve multiple purposes: frequency control, region selection, and brightness variation elimination, thereby reducing the need for additional dedicated circuits

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS12354560B2Display device with improved display quality

Publication Date: 2025.07.08 SAMSUNG DISPLAY CO LTD

AI summary

A display device may include a display panel, a data driving circuit, and a scan driving circuit which outputs first scan signals and second scan signals. The scan driving circuit includes a plurality of stages. Each of the stages may include a masking circuit outputting a first scan signal to a first output terminal, a driving circuit outputting a second scan signal to a second output terminal, and an auxiliary circuit including an auxiliary transistor which is a normally closed and connected between the masking circuit and the driving circuit.