LCD projectors have been widely used in business applications typically for business presentations, educational sessions, etc.
Liquid crystal display panels have a number of advantages that make them useful in optical projectors, especially projectors for displaying computer generated images and portable projectors. A LCD projector includes one or more transmissive liquid crystal displays as light valves that control light from an illumination system to form display images that are directed to the display screen by projection optics. Typically, a liquid crystal based display device may include an illumination source, a plurality of liquid crystal display panels arranged in a stack, and focusing optics for imaging a composite display generated by the panels on an image surface. Conventional liquid crystal display systems include a mosaic of color selective filters positioned over the liquid crystal display element to separate the white light into its constituent color components to render a full color display. Many color LCD projectors typically have one color LCD, such as an active matrix or passive matrix liquid crystal display, that controls red, green and blue spectral components of light to form a display image. Color liquid crystal display projectors generate display images and project them onto display screens. The display images may be formed by transmitting light from a high-intensity source of polychromatic or white light through a liquid crystal display (LCD). LCD projectors frequently are positioned on a table, cart, or other flat surface below the viewers' line-of-sight to the display screen.
