![]() Titanium dioxide is a bright white colour, but greater gains can be accomplished with materials that reflect more of the light parallel to projection axis and less off-axis.įrequently quoted gain levels of various materials range from 0.8 of light grey matte screens to 2.5 of the more highly reflective glass bead screens. This is a measure of reflectivity of light compared to a screen coated with magnesium carbonate, titanium dioxide, orīarium sulfate when the measurement is taken for light targeted and reflected perpendicular to the screen. One of the most often quoted properties in a home theater screen is the gain. See the respective articles for more information. These include non-solid screens, inflatable screens and others, and can be inexpensively made at home. Specialty screens may not fall into any of these categories. In the latter screens, the fabric can rarely stay immobile if there are currents of air in the room, giving imperfections to the projected image. Tensioned models attempt to keep the fabric flat and immobile, whereas the not tensioned models have the fabric of the screen hanging freely from their support structures. These can be used when it is impossible or impractical to mount the screen to a wall or a ceiling.īoth mobile and permanently installed pull-down screens may be of tensioned or not tensioned variety. Mobile screens usually use either a pull-down screen on a free stand, or pull up from a weighted base. ![]() It is very good for advertising on store windows. In the opaque state, projected image on the screen can be viewed from both sides. Switchable projection screens can be switched between opaque and clear. Electric screens are usually raised or lowered using either a remote control or wall-mounted switch, although some projectors are equipped with an interface that connects to the screen and automatically lowers the screen when the projector is switched on and raises it when the projector is switched off. Electric screens are similar to pull-down screens, but instead of the screen being pulled down manually, an electric motor raises and lowers the screen. These are often larger screens, though electric screens are available for home theater use as well. They are often used in home theater and professional environments where the screen does not need to be recessed into the case.Įlectric screens can be wall-mounted, ceiling-mounted or ceiling recessed. These commonly use painted fabric that is rolled in the screen case when not used, making them less obtrusive when the screen is not in use.įixed-frame screens provide the greatest level of uniform tension on the screens surface, resulting in the optimal image quality. Pull-down screens (also known as manual wall screens) are often used in spaces where a permanently installed screen would require too much space. Screens can be further designed for front or back projection, the more common being front projection systems, which have the image source situated on the same side of the screen as the audience.ĭifferent markets exist for screens targeted for use with digital projectors, movie projectors, overhead projectors and slide projectors, although the basic idea for each of them is very much the same: front projection screens work on diffusely reflecting the light projected on to them, whereas back-projection screens work by diffusely transmitting the light through them.Īn overhead projector projecting onto a pull-down screen Flat or curved screens may be used depending on the optics used to project the image and the desired geometrical accuracy of the image production, flat screens being the more common of the two. Uniformly white or grey screens are used almost exclusively as to avoid any discoloration to the image, while the most desired brightness of the screen depends on a number of variables, such as the ambient light level and the luminous power of the image source. ![]() Another popular type of portable screens are inflatable screens for outdoor movie screening ( open-air cinema). ![]() Projection screens may be permanently installed, as in a movie theater painted on the wall or portable with tripod or floor rising models as in a conference room or other non-dedicated viewing space. Home theater projection screen displaying a high-definition television imageĪ projection screen is an installation consisting of a surface and a support structure used for displaying a projected image for the view of an audience. ![]()
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