A rear projection screen is a type of screen which is designed to be used with rear projection presentations. In rear projection, the image passes through the screen to the eyes of the viewer, rather than being reflected against the front of the screen. There are some definite advantages and disadvantages to using rear projection for image displays. Many stores which carry projection suppliers carry rear projection screens along with other equipment options.
When a rear projection screen is used, the projector is mounted behind the screen. As with other types of projection, it is necessary to adjust the intensity of the light and focus to get the best image. In rear projection, the light intensity generally needs to be quite high, as the light must pass clearly through the screen.
There are a variety of situations in which rear projection can be appropriate. A rear projection screen for home use can be used to set up a home theater system, and these screens can also be used in offices, schools, and other presentation environments. Some movie theaters utilize rear projection, and stage productions may have a rear projection screen to create backdrops and scenery effects.
One of the big advantages to rear projection is that the lights in the room can be on when images are projected, and viewers will still be able to see clearly. This can be useful in presentations, where people may want to take notes or engage with the speaker, which can be hard to do when the lights are off. A major disadvantage is the tendency to develop a hot spot, a bright point in the screen created by the high intensity light from the projector. A rear projection screen also has a more limited viewing cone; if people sit in the wrong place, the image will be distorted or of poor quality.
It is also necessary to have ample space behind a rear projection screen for the projector. The projector cannot be butted directly up against the screen, especially in the case of a large screen, and this can cause space problems in a venue with limited working room. The necessary extra space must also be kept clear to avoid projecting shadows onto the screen, which means that it cannot be utilized for storage or the installation of a sound system. By contrast, with front projection, the projector can be mounted up high in the back of a room, taking up minimal space.
