frontprojection

Front projection is a display method in which a projector is placed on the same side of the screen as the viewer, projecting an image onto a screen for viewing. This contrasts with rear projection, where the projector sits behind the screen. Front projection is widely used in home theaters, classrooms, and conference rooms because it can produce very large images at relatively low cost.

A typical front-projection setup includes a projector with a light source (lamp, LED, or laser) and an imaging technology (DLP, LCD, or LCoS) and a projection screen. The distance from projector to screen, determined by the throw ratio, sets the image size. Short-throw and ultra-short-throw projectors place the unit close to the screen to minimize shadows, while standard throw models require more distance. Screen surfaces vary, with matte white screens offering neutral brightness, gray screens reducing perceived contrast in bright rooms, and ambient light rejecting (ALR) screens helping preserve image quality under ambient illumination.

Advantages of front projection include the ability to produce very large images and lower cost per diagonal inch compared with many alternatives, along with flexible room layouts and easier integration into existing spaces. Limitations include sensitivity to ambient light and potential shadows when viewers or objects pass in front of the projector beam, as well as the need for a screen that matches the projector and room conditions.

In larger installations, multiple front-projectors can be used with blending and warping to create a single large image. See also projection screen, projector, projection mapping.