In the last several years, holographic elements have been introduced into a wide array of display applications. Holographic Reflectors are incorporated with liquid crystal displays to shift optimum viewing angle away from specular glare and raise brightness by concentrating light at a convenient viewing angle. Reflectors can be produced in blue, green, gold, red, or white colors. Denso GlassVision (R) projection screens incorporate transmission holograms to efficiently direct projected light to the viewer in a screen that reverts to clear glass when the projection image is turned off. JVC has introduced a large-screen HDTV that uses a holographic color filter to separate blue, green, and red light from the illumination beam, and direct the sorted colors to the appropriate color pixel, raising brightness with a passive component. Most recently, HOE prototypes have been produced to improve the efficiency of portable liquid crystal color displays. Front diffusers are affixed to the face of reflective color LCDs and direct output light from the LCD to the viewer at a convenient viewing angle in a concentrated view cone. Reflective Color Filters are pixellated diffuse reflectors internal to the LCD structure and aligned to the LCD matrix. These reflective filters provide higher brightness, larger color gamut, and better color saturation than is possible with absorptive color filters. Finally, compensation films based on a hybrid structure including a holographic gating are under development to provide wider view angle in direct-view LCD's.
