Abstract: A filter for reducing the glare of a viewing screen caused by ambient light and increasing the viewing area constructed of a substantially transparent sheet of material having first and second faces. The first face is substantially planar while the second face has a plurality of V-shaped grooves, each groove being formed by two walls. The geometry of the V-shaped grooves is such that ambient light enters the filter and becomes trapped therein due to internal reflection.

Abstract: A filter for reducing the glare of a viewing screen caused by ambient light is comprised of a substantially transparent sheet of material having first and second faces. The first face is substantially planar while the second face has a plurality of V-shaped grooves, each groove being formed by two walls. The geometry of the V-shaped grooves is such that ambient light enters the filter and becomes trapped therein due to internal reflection.

Abstract: An anti-glare device for a transmission screen includes a layer of transparent material having a front surface and a back surface. The front surface is provided with a saw-toothed profile, while the back surface is bonded to a circular polarizer. By mounting the anti-glare device a predetermined distance in front of a transmission screen, glare due to ambient light can be substantially eliminated without producing echo images.

Abstract: An overlay for use on a transmission screen is disclosed which reduces front face glare by providing a plurality of inclined surfaces on the front surface thereof to deflect ambient light away from the viewing area. A coating of opaque material is applied to the peaks of the inclined surfaces to substantially eliminate "echos" of the image being viewed.

Abstract: A transparent front projection screen is disclosed having a plurality of ridges on the back thereof interrupted by flat portions and a plurality of curved sawtooth shaped ridges on the front thereof. The back ridges serve as a prism like element for reflecting the light by internal reflection which is incident thereon from predetermined directions. The flat surfaces on the back of the screen pass light incident from certain undesired directions. The sawtooth shaped ridges on the front of the screen serve as elements for developing a vertical spread of light but eliminates front face reflection problems.The disclosure also teaches the proper location of a projector when used with a transparent front projection screen as described above.

Abstract: A front projection screen manufactured from transparent material is disclosed. The back side of the screen includes a plurality of prism-like elements so that light incident upon the screen from a preferred direction is totally reflected by the screen, while light incident upon the screen from other directions will pass therethrough. The parallel ridges are intermittently interrupted by repeating surfaces formed parallel to the plane of the front surface of the screen. The sides of the prism-like elements on the back surface of the screen are curved to provide dispersion in a horizontal plane, while the front surface of the screen has segments of cylindrical columns formed thereon perpendicular to the prism-like elements to form an angular light spread in a vertical plane.

Abstract: A front projection screen is disclosed which is made from a transparent material. Prism-like elements are formed on the backside thereof so that light incident upon the screen from a preferred direction will be totally reflected by the screen while light incident upon the screen from other directions will pass therethrough. Sides of the prism-like elements are curved for dispersion in the horizontal plane while the front surface of the projection screen has segments of cylindrical columns formed thereon perpendicular to the prism-like elements to provide an angular spread in the vertical plane. The thickness of the screen is between 30 percent and 70 percent of the focal length of the cylindrical columns to allow the screen to be tilted in the vertical plane.