MVA Liquid Crystal Display Driving Circuit for Two-Step Response
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liquid crystal display devices in the MVA mode suffer from a two-step response issue, leading to prolonged response times and inadequate performance in dynamic picture display, due to the alignment regulating structure and dielectric anisotropy of the liquid crystals, which impairs high-speed response characteristics.
Innovation Solution
A liquid crystal display device with an alignment regulating structure on the substrates and a control circuit that adjusts the voltage difference between frames to account for changes in liquid crystal capacitance, ensuring a greater voltage change in the first frame and a lower voltage in subsequent frames to maintain brightness, thereby preventing the two-step response and enhancing response speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If an alignment regulating structure is used to regulate liquid crystal alignment in MVA mode, then high contrast and wide viewing angle are achieved, but response time is prolonged due to two-step response
Solution Approach 1:
The patent applies dynamic voltage adjustment across different frames to compensate for liquid crystal capacitance changes. The driving circuit dynamically modifies the voltage applied to the liquid crystal in subsequent frames based on the alignment state, enabling the system to adapt to the two-step response characteristic and maintain high-speed response while preserving the high contrast and wide viewing angle benefits of MVA mode
Solution Approach 2:
The patent changes the voltage parameter dynamically frame-by-frame. By adjusting the voltage applied to the liquid crystal in subsequent frames based on the capacitance change caused by alignment regulation, the system compensates for the two-step response effect and achieves improved response time while maintaining the alignment benefits of the MVA mode
2Stability of the object's composition
If conventional MVA mode is used with alignment regulating structure, then vertical alignment is achieved, but response characteristics are insufficient for dynamic picture display
Solution Approach 1:
The patent introduces dynamic voltage control in the driving circuit that adjusts parameters frame-by-frame. This dynamic adjustment compensates for the slow response of vertically aligned liquid crystal in MVA mode, enabling the system to maintain stable vertical alignment while achieving response characteristics suitable for dynamic picture display
Solution Approach 2:
The patent implements a feedback mechanism where the driving circuit monitors the liquid crystal capacitance changes and adjusts the applied voltage in subsequent frames accordingly. This feedback loop compensates for the delayed response of vertically aligned liquid crystal, improving dynamic picture display performance while preserving the vertical alignment stability
3Illumination intensity
If voltage is applied to change liquid crystal alignment, then brightness changes occur, but two-step response causes prolonged time to reach target brightness
Solution Approach 1:
The patent applies a preliminary voltage adjustment in the first frame that anticipates the capacitance change. By pre-compensating for the expected capacitance increase in subsequent frames, the system reduces the time to reach target brightness and eliminates the two-step response delay, achieving faster brightness transitions
Solution Approach 2:
The patent changes the voltage parameter in a frame-dependent manner. The driving circuit applies different voltage levels in the first frame versus subsequent frames, adjusting the electrical parameters to compensate for capacitance changes and achieve faster, more direct brightness transitions without the two-step response delay
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
The solution effectively suppresses the two-step response, allowing for faster brightness changes and improved response characteristics, enabling the liquid crystal display device to handle dynamic images effectively by maintaining maximum brightness after the first frame without additional frames.
Implementation Method 1
the vertically aligned type liquid crystal having a negative dielectric anisotropy is regulated for the alignment
Implementation Method 2
the electric charge is stored in the liquid crystal capacitance Clc and in the storage capacitor Cs
Data Source
AI summary
In driving a liquid crystal display device having an alignment regulating structure for regulating liquid crystal, when the display state of the pixel is to be changed from a dark display to a bright display, a difference between the magnitude of a voltage Vd4 applied to the liquid crystal of the pixel at the beginning of the first frame and the magnitude of a voltage Vd3 applied to the liquid crystal of the pixel in the second frame or a subsequent frame, is set to be greater than a voltage Vod that decreases in the first frame due to an increase in the liquid crystal capacitance of the pixel.