LCD Monitors

LCD stands for liquid crystal display, and is used in television and computer monitor screens, as opposed to cathode ray or plasma for the visual output portion of a display system. The earliest liquid crystal display technology was used in an LCD panel television.

The early liquid crystal display television had some difficulties with displaying fast paced action and had very restricted viewing angles. These display problems have mostly been overcome in recent years and the market for liquid crystal display televisions is booming greater than ever before. This is especially true in Asia.

For many years it was commonly believed that LCD technology was best suited only for smaller size television screens, and could not compete with plasma technology at bigger sizes. This view has been undermined by the announcements of ever-larger liquid crystal display panels manufactured by companies such as Samsung, Sharp Corporation, and LG Philips.

For example, in November 2004, forty to forty-five inch television screens were widely available and Sharp Corporation has just announced the completed manufacture of a sixty-five inch liquid crystal display panel. Also in 2004, Sony and Samsung combined forces in order to construct a factory in South Korea that was intended to manufacture more than 6,000 LCS panels per month.

Then in March of 2005, a eighty-two inch HDTV TFT panel was produced by Samsung. Samsung created the world’s largest liquid crystal display line. With viewing angles of 180 degrees achieved by Samsung’s proprietary technology, the 12.44 million thin-film transistors achieve full HD image quality of 6.22 million pixels. The primary liquid crystal display manufacturers have each pledged billions of dollars of investment into LCD research and production over the next several years. Television is expected to be the greatest key market, with LCD computer monitors running second.

Television and computer screens based on PVA and S-PVA LCD panels offer quite good ‘angle of view’, and also deliver a decent contrast ratio for viewing brighter scenes and dark scenes in dark rooms. Alternatively, a television made from a creative electronics manufacturer will add some light on the wall behind the screen in order to help make dark screens look darker. Still, PVA and S-PVA display panels usually have trouble with ghosting when switching between different shades of dark colors.

Moving pictures on a CRT television do not show any kind of ‘ghosting’ or ‘trails’ because the CRT’s phosphor, which is charge by the striking of electrons, emits nearly all of the light in very short time, when compared to the refresh time. With liquid crystal display panels, each pixel emits light of a set intensity for a full refresh period, plus the time it takes for the unit to switch to the next state.

The second time is referred to as the response time, and can be shortened by the panel design, as well as by using a technique called overdriving, but this type of fix can go down to only as short as the refresh period. Though this is usually enough for film-based viewing material, film producers still try to make objects of interest relatively immobile in the frame so that any residual shaking will not be noticed.

Two emerging liquid crystal display technologies strive to solve the shaking and refresh problems with the use of a backlight that is fired during shorter portions of time then the refresh portion. This process enhances the dread flicker problem, because the eye is able to sense the flicker. Yet another approach is to double the refresh rate of the liquid crystal display panel and construct the frames in such a way that motion is compensated for and allows the viewer to switch them on or off when viewing film or video based materials.

Deon Melchior is the Editor and Publisher of Article Click. For more FREE articles for your ezine and websites visit ArticleClick.com. Article Click is a free content article directory. This means that as a publisher you may reprint the articles that are included in our site, as long as the article is unedited and the author box is included with it's live hyperlinks.