Liquid Crystal Display Pixel Cell Three-Period Charging Method
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Low frequency driving schemes for static images in liquid crystal displays result in visible flicker and light intensity loss, particularly at low to middle gray levels, due to inefficient voltage charging periods.
Innovation Solution
A three-period charging method for pixel cells, where the pixel cell is charged with a target voltage, then a post voltage, and finally a base voltage, with the post voltage falling between the target and base voltages, to reduce flicker and improve light intensity symmetry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If a low frequency driving scheme is applied to refresh static images, then power consumption is reduced, but visible flicker is generated and light intensity is lost
Solution Approach 1:
The refresh period is segmented into three distinct periods: a first period for charging to target voltage, a second period for charging to post voltage, and a third period for charging to base voltage. This segmentation allows the pixel cell to be charged in stages rather than all at once, reducing the harmful flicker effect while maintaining low power consumption characteristics of low frequency driving
Solution Approach 2:
The pixel cell is pre-charged to a post voltage (intermediate voltage between base and target voltages) before final charging to the target voltage. This preliminary action smooths the voltage transition and reduces the abrupt changes that cause visible flicker during low frequency driving
2Use of energy by stationary object
If a low frequency driving scheme is applied to refresh static images, then power consumption is reduced, but light intensity loss occurs
Solution Approach 1:
The voltage charging parameters are changed by introducing a post voltage intermediate between the base voltage and target voltage. This parameter change in the charging process ensures that the pixel cell voltage transitions smoothly through intermediate states, maintaining consistent light intensity output during low frequency driving and preventing light intensity loss
Data Source
AI summary
A display including a pixel cell is provided. When the liquid crystal display is displaying a static image, the pixel cell is refreshed through a first period, a second period, and a third period in sequence. In the first period, the pixel cell is charged by a target voltage. In the second period, the pixel cell is charged by a post voltage. In the third period, the pixel cell is charged by a base voltage until next of the first period. The post voltage is between the target voltage and the base voltage. In addition, a driving method for a display is also provided.