Abstract: An overhead projector including a Fresnel lens, a single element meniscus projection lens having a concave side and a convex side, and a folding mirror placed in an optical path between the Fresnel lens and the projection lens. The projection lens is oriented to have the concave side optically facing the Fresnel lens. The optical design of the overhead projector follows the following equation, FFres=(FLens(MLens+1)/MLens−SLD)/(MFres+1), where the Fresnel lens has a focal length FFres, and a magnification MFres, the projection lens has a focal length FLens and a magnification MLens, and SLD is the distance from the stop position and the projection lens.

Abstract: A front image projection device and corresponding method are disclosed that utilize a shaped imager component to pre-distort an input image and thereby compensate for the distortion expected in a screen image. The front projection device includes projection components, image generating components, and illumination components. The shaped image component may compensate at least in part for distortion introduced due to the components of the projection system. The physical configuration for the shaped imager may be determined through a modeled or actual ray trace through the projection system, and the resulting physical configuration may be a geometric shape having a curved top, a curved bottom and curved sides.

Abstract: A front projection system and associated method are disclosed that correct distortion for a front projector device. The front projector device is characterized by off-axis optics and a throw-to-screen diagonal ratio of at most 1 which generate distortion including pincushion, keystone and anamorphic distortion components. Further, the projection device has an electronic distortion correction component operable to pre-distort an image prior to projection in order to correct for the pincushion, keystone and anamorphic distortion components of the projector device. Further, an associated method is also disclosed for correcting distortion generated in a projection system by a combination of optical and electronic correction. The method comprises setting a limit on the amount of image information that is acceptable to lose through the optical components, and selecting an optical solution is comprising optics having inherent distortion within the set limit.

Abstract: An overhead projector including a Fresnel lens, a single element meniscus projection lens having a concave side and a convex side, and a folding mirror placed in an optical path between the Fresnel lens and the projection lens. The projection lens is oriented to have the concave side optically facing the Fresnel lens. The optical design of the overhead projector follows the following equation, FFres=(FLens(MLens+1)/MLens−SLD)/(MFres+1), where the Fresnel lens has a focal length FFres, and a magnification MFres, the projection lens has a focal length FLens and a magnification MLens, and SLD is the distance from the stop position and the projection lens.

Abstract: A front image projection device and corresponding method are disclosed that utilize a shaped imager component to pre-distort an input image and thereby compensate for the distortion expected in a screen image. The front projection device includes projection components, image generating components, and illumination components. The shaped image component may compensate at least in part for distortion introduced due to the components of the projection system. The physical configuration for the shaped imager may be determined through a modeled or actual ray trace through the projection system, and the resulting physical configuration may be a geometric shape having a curved top, a curved bottom and curved sides.

Abstract: A front projection screen and associated system and method are disclosed that utilize a back structured layer and a front diffusing layer to provide improved viewable image quality. The structured layer is formed with a plurality of grooves and can operate to direct light into a defined audience view region. The diffusing layer is coupled to the structured layer and is formed from a matte polyester film to provide dry erase capability on a front surface of the diffusing layer. For example, the matte polyester film can be TEKRA Marnot XL matte Melinex polyester film. Further, the structured layer can be formed as an acrylate linear prismatic structure having a gloss white coating. The acrylate linear prismatic structure and the matte polyester film can be coupled, for example, by lamination or can be coupled by being extruded as a unitary construction.

Abstract: A front projection system and associated method are disclosed that correct distortion for a front projector device. The front projector device is characterized by off-axis optics and a throw-to-screen diagonal ratio of at most 1 which generate distortion including pincushion, keystone and anamorphic distortion components. Further, the projection device has an electronic distortion correction component operable to pre-distort an image prior to projection in order to correct for the pincushion, keystone and anamorphic distortion components of the projector device. Further, an associated method is also disclosed for correcting distortion generated in a projection system by a combination of optical and electronic correction. The method comprises setting a limit on the amount of image information that is acceptable to lose through the optical components, and selecting an optical solution is comprising optics having inherent distortion within the set limit.