Cholesteric LCD Driving Waveform for Ghost Image Elimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The current driving method for cholesteric liquid crystal displays experiences interference between scanning time sequences, leading to ghost images that degrade image quality.
Innovation Solution
Applying a ghost elimination voltage during the Selection phase of the Nth scanning time sequence and the Selection phase of the Mth scanning time sequence, with a duration of T, to stabilize the liquid crystals before the next imaging process, thereby eliminating ghost images.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the Selection phase signal of the N+1th scanning time sequence is directly connected to the Selection phase signal of the Nth scanning time sequence, then the driving method is simple, but the Evolution phase voltage of the Nth scanning time sequence is interfered with, causing ghost images to appear
Solution Approach 1:
The patent introduces a ghost elimination voltage applied during the Selection phase to preemptively eliminate interference from the next scanning time sequence before it can affect the current image display. This preliminary action prevents the harmful effect of voltage interference on the Evolution phase, thereby eliminating ghost images while maintaining the direct connection structure of the driving method
Solution Approach 2:
The ghost elimination voltage serves as a counter-action that is applied in advance during the Selection phase to offset the harmful interference that would otherwise occur during the Evolution phase. By applying this opposing voltage signal beforehand, the patent prevents the interference from the N+1th scanning time sequence from degrading the image quality of the Nth scanning time sequence
2Manufacturing precision
If the ghost elimination voltage is applied during the Selection phase, then the liquid crystals are stabilized and ghost images are eliminated, but the driving waveform becomes more complex
Solution Approach 1:
The patent merges the ghost elimination function with the existing Selection phase driving waveform. Instead of adding a separate ghost elimination phase or modifying the overall driving structure, the ghost elimination voltage is integrated into the Selection phase time window, thereby achieving ghost image elimination while minimizing the increase in driving waveform complexity
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 method effectively stabilizes the liquid crystals in the Nth scanning time sequence, ensuring clear display of the Mth scanning time sequence images without interference, enhancing image quality.
Implementation Method 1
Cholesterol liquid crystal molecules exhibit bistable characteristics, meaning they can maintain their arrangement without needing additional external energy. When a voltage is applied, the alignment of these cholesterol liquid crystal molecules can be controlled to switch between two stable states: a focal conic alignment state and a planar alignment state.
Implementation Method 2
The three-phase driving method is designed to address the hysteresis characteristics between the focal-conic state and the vertical alignment state.
Data Source
AI summary
A driving method of cholesteric liquid crystal display is provided. A liquid crystal driving unit is used to output row driving voltage to multiple row circuit structures. Sequentially column driving voltage is outputted to multiple column circuit structures in a scanning manner. Scanning a column circuit structure takes one scanning time sequence. When starting the Nth time sequence of pixels to present the image, a ghost elimination voltage is applied to eliminate the image of the Mth time sequence and present it at the image position of the Nth time sequence, where M=N+1 and the ghost elimination voltage is applied at T. By doing so, the phenomenon of ghosts appearing on cholesteric liquid crystal displays can be improved, and the imaging quality of cholesteric liquid crystal displays can be improved.