Rca Inc.

The Mead Corporation

Bertram VanBreemen

John L Dressler

Biswa N Ganguly

Tom W Branton

James R Young

Duane L Roberts

William L Wilson

A rear projection television receiver has an image source, first and second mirrors, and a screen. Light travels from the image source to the screen along a first light path via the first and second mirrors and along a second path that bypasses the mirrors. A light baffle assembly comprising a plurality of elongated baffle elements is located in both the first and second light paths. The angle of the individual baffle elements is adjusted so that light rays are unaffected along the first light path and substantially completely blocked along the second light path.

Apparatus for preventing virtual images in projection television

A rear projection television receiver incorporates red, green and blue-image producing kinescopes and a screen which includes a prism lens arrangement. The prism lens comprises a number of prism lens elements made up of a plurality of lens surfaces or facets. The prism lens forms the vertical audience envelope of the screen, which results from a combination of the vertical audience envelope contributed by the differently angled facets. Planes normal to the horizontal centerline of the faceplates of the red and blue image-producing kinescopes are displaced with respect to a plane normal to the horizontal centerline of the faceplate of the green image-producing kinescope in order to correct vertical color shift.

Vertical color shift correction in a rear projection television screen

A rear projection television receiver incorporates a screen which includes a prism lens arrangement. The prism lens comprises a number of prism lens elements made up of a plurality of lens surfaces or facets. The individual facets of a given prism lens element form different angles with respect to a vertical plane. The prism lens forms the vertical audience envelope of the screen, which results from a combination of the vertical audience envelope contributed by the differently angled facets, thereby giving a great deal of control over the shape of the envelope.

Rear projection television screen incorporating a prism lens

A mounting frame for optical components of a projection television receiver comprises tubular members interconnected to form a skeletal structure. The mounting frame incorporates sub-frames to which the projection tubes, mirror assemblies and screen are mounted. The frame forms a rigid structure which maintains the positional relationship between the optical components in spite of environmental or other changes, thereby facilitating assembly and adjustment of the projection television receiver.

Projection television receiver with unitary optics frame

A rear projection television receiver comprising a rear projection screen that incorporates a compound Fresnel field lens. The field lens comprises two circular Fresnel lenses that together provide the total refraction for the light impinging on the screen. The angle of incidence of the light striking the individual Fresnel elements is reduced, thereby reducing the amount of light reflected from the Fresnel surfaces. The screen efficiency, especially near the edges of the screen, is thereby increased.

Rear projection television screen having a multi-surface Fresnel lens

A screen for a rear projection television receiver comprises a circular Fresnel lens element and a lenticular lens array. In order to adjust the location of the vertical audience envelope to optimize screen brightness for different viewing positions, the center of the Fresnel lens is displaced with respect to the center of the viewing screen. The principal light rays passing through the Fresnel lens are bent with respect to the lenticular array, thereby angling the vertical audience envelope with respect to the screen.

Projection television screen having a selected audience envelope

Glass fibers having an etchable or leachable core are used to fabricate glass nozzle arrays. A plurality of fibers are aligned in spaced parallel relationship with one another, and their major longitudinal portions are encapsulated with either a resin material or solder glass to form a block of material. This block is sliced orthogonally to the longitudinal axes of the fibers to form thin sections of nozzle arrays. After lapping and polishing, the inner cores of the glass fibers are etched out to form orifices. The use of solid core glass fibers prevents the nozzles from filling or becoming clogged with debris and dust from preceding forming operations.

Growing community of inventors

Indianapolis, IN, United States of America

Bertram VanBreemen