Editing LCD projector (section)

{{short description|Type of video projector}}
[[File:LCDprojLiesegang3.jpg|thumb|Liesegang LCD Projector]]
An '''LCD projector''' is a type of [[video projector]] for displaying video, images or computer data on a screen or other flat surface. It is a modern equivalent of the [[slide projector]] or [[overhead projector]]. To display images, LCD ([[liquid crystal display|liquid-crystal display]]) projectors typically send light from a [[metal-halide lamp]] through a [[Prism (optics)|prism]] or series of [[dichroic filter]]s that separates light to three [[Polycrystalline silicon|polysilicon]] panels{{spaced ndash}}one each for the red, green and blue components of the video signal. As polarized light passes through the panels (combination of polarizer, polysilicon LCD panel and analyzer), individual pixels can be opened (made transparent controlled by electricity) to allow light to pass or closed (made opaque controlled by electricity) to block the light. The combination of open and closed pixels can produce a wide range of colors and shades in the projected image. 

[[Metal-halide lamp]]s are used because they output an ideal color temperature and a broad spectrum of color. These lamps also have the ability to produce an extremely large amount of light within a small area; current projectors average about 2,000 to 15,000 American National Standards Institute (ANSI) lumens. 

Other technologies, such as [[digital light processing]] (DLP) and [[liquid crystal on silicon]] (LCOS) are also becoming more popular in modestly priced video projection.