Liquid Crystal Display Signal Processing Frequency Adaptation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Liquid crystal panels fail to display normally when the vertical synchronization frequency of the television signal exceeds 60 Hz due to increased response time, which is not addressed by existing over-driving methods.

Innovation Solution

A device and method for selecting an image processing function that enables either over-driving or frame buffering based on the frequency of the image signal, using a combination of an analog-to-digital converting unit, frame buffer unit, and over-driving unit to adjust the image processing according to the frequency, allowing for resolution adjustments and memory management to optimize display performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If over-driving voltage is applied to reduce liquid crystal response time, then response time is reduced from 3*TF to TF, but the liquid crystal panel cannot display normally when the vertical synchronization frequency exceeds 60 Hz

Engineering Contradiction:
Improveliquid crystal response timeVSAvoiddisplay normal operation at high frequency
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The patent implements dynamic selection between frame buffering mode and over-driving mode based on the vertical synchronization frequency of the input signal. When the frequency exceeds 60Hz, the system automatically switches to frame buffering mode; when it is 60Hz or below, it uses over-driving mode. This dynamic adaptation resolves the contradiction by allowing the system to optimize for speed when appropriate while ensuring reliability when needed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the operating parameters of the liquid crystal display system based on the input signal frequency. By detecting the vertical synchronization frequency and adjusting the driving mode accordingly, the system can maintain proper display operation across different frequency conditions while still achieving fast response times when the signal frequency allows.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If frame buffering function is enabled to support high frequency signals, then display normal operation is achieved, but memory capacity requirements increase

Engineering Contradiction:
Improvedisplay normal operation at high frequencyVSAvoidmemory capacity
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The patent segments the operating conditions into two distinct modes: frame buffering mode for high frequency signals and over-driving mode for lower frequency signals. This segmentation allows the system to use memory-intensive frame buffering only when necessary, rather than always requiring large memory capacity. The conditional activation based on frequency detection reduces the average memory capacity requirements while maintaining reliability when needed.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2320409B8Device and method of selecting one of two video signal processing functions for a liquid crystal display
Publication Date: 2016.05.25 HANNSTAR DISPLAY CORP

AI summary

A device for selecting an image processing function (22) is provided. The device (22) comprises an analog-to-digital converting unit (222) outputting a first image (223) in response to an image signal (221) having a first frequency (f1); a frame buffer unit (2246) having a frame buffering function; and an over-driving unit (2241) having an over-driving function, wherein the device for selecting the image processing function (22) enables one of the frame buffering function and the over-driving function according to the first frequency (f1).