Explain LCD MS Response

Liquid crystal display panels contain liquid crystal molecules -- rod-like molecules that behave something similar to a liquid and something like a solid -- sandwiched in between glass or plastic plates. When an electrical current is passed with the liquid crystal, the molecules twist to permit or refuse the passage of light. The time they take to do this -- measured in thousandths of a second or milliseconds -- is called the response time of the LCD panel.

Response Period

Strictly speaking, the response time of an LCD panel may be the time it takes for an individual picture element, or even pixel, to change from fully off, or black, to completely on, or white and back again. However, LCD pixels tend to be rarely fully off or fully on, but rather period among various shades of gray, or grayscale levels. The voltage applied to the liquid crystals to create a black to white transition is higher than the voltage applied to create a gray to gray transition, so a black to white transition is usually faster. In other words, to be truly meaningful, an answer time specification must include both types of transition.

Increase and Fall Time

Manufacturers measure response time in other ways, but one common method is to measure the time taken for any pixel to make the transition from 10 percent from the required brightness to 90 percent of the required brightness and again. Technically, these response times are known as “rise time” as well as “fall time. ”

Image Artifacts

Generally speaking, response time has an indication of how well an LCD panel can show moving images. The lower the response time, the faster the panel can display each successive frame in a moving image and the lower the probability of image artifacts, which are visible as blurring or “ghosting” from the image. Image artifacts can occur not only when watching moving pictures, but also when scrolling through content with an LCD computer monitor.

Typical Values

According to CNET Evaluations, a response time of 16 milliseconds is fast sufficient to play back DVD content, although some image distortion and ghosting might be evident. For watching TV broadcasting and movies and playing game titles, without distortion, an LCD TV or computer monitor will need a response time of between 12 and 15 milliseconds. Nevertheless, response times are falling all the time, such which, as of November 2011, LCD panels with a response time of three or four milliseconds are available.