(a) Field of the Invention
The present invention relates to a liquid crystal display and a drive method thereof, in which liquid crystal molecules respond fast even at data voltages of an intermediate grayscale level. More particularly, the present invention relates to a liquid crystal display and a drive method thereof, which improves a liquid crystal response speed with respect to the application of a gate voltage of a twisted nematic liquid crystal display.
(b) Description of the Related Art
A twisted nematic liquid crystal display (TN LCD) has the advantages of enabling control at very thin profile configurations, and of consuming very little power. However, the drawbacks of TN LCDs are that they have slow response speeds with respect to applied voltages, and a limited viewing angle.
FIG. 1 shows a graph of response curves when a voltage is applied to pixels of a TN LCD.
As shown in FIG. 1, a response time of twisted nematic liquid crystals is roughly 15–17 ms from the moment a voltage is applied, and when the applied voltage is switched off, a response time of approximately 20 ms is required. Accordingly, it is difficult to realize images containing a large amount of data.
Various configurations are used to improve response speeds. These include the surface stabilized ferroelectric liquid crystal display (SSFLCD) and the anti-ferroelectric liquid crystal display (AFLCD). However, in these LCDs, alignment and the display of grayscale levels are difficult to obtain, and a high reset voltage is required such that practical applications of the LCDs are not fully feasible.
In more traditional configurations, the slow response speeds make the display of certain images (e.g., moving images) unclear since these images require the display of large amounts of grayscale levels during a short interval of time. Therefore, the TN LCD particularly needs an improvement in response speeds.