Abstract: A projection television receiver having red, green and blue image projectors for respective images of different colors and a high gain projection screen formed by at least one hologram disposed on a substrate superimposed on at least one light transmissive panel. The high gain holographic screen provides increased horizontal viewing performance over lenticular (e.g., fresnel) screens without reliance on screens having wide horizontal half viewing angles.

Abstract: A projection television has a screen with a three dimensional hologram on a film substrate for collecting light over a range of incident angles and redirecting the light more nearly forward. Vertical and horizontal holograms can have varying gain across a horizontal viewing span of ±40° and a vertical viewing span of ±20° can be stacked. Image projection tubes project an image onto at least one mirror that reflects the image along an optical path that converges at an angle of projection, &phgr;, between about 0° and 30° relative to an axis orthogonal to the screen. Each tube can have a separate mirror. The hologram redirects the images reflected to an angle of display relative to the orthogonal axis of the screen of from 0 to 5°.

Abstract: A projection television is provided comprising at least three image projectors for projecting respective images of different colors onto a holographic projection screen. One of the projectors has a first, shortest optical path disposed in a substantially orthogonal orientation with the holographic projection screen and at least two of the projectors are disposed in adjacent, stepped-relation to one another and have respective optical paths that are (i) selectively defined by the stepped-relation of the projectors; and (ii) converge toward the first optical path in a non-orthogonal orientation so as to define angles of incidence corresponding to a lowest level chromatic aberration of the images by the holographic projection screen. The projection screen is formed by a three dimensional hologram representing a three dimensional array of lenticular elements disposed on a substrate.

Abstract: An East-West switching transistor is coupled between a flyback transformer primary winding and a horizontal deflection output transistor circuit to control retrace energy to obtain an East-West modulation of the deflection current amplitude as required for East-West pincushion raster correction. A pair of series coupled first and second capacitors forming a capacitive voltage divider are coupled to a retrace resonant circuit that includes the deflection winding via a sampling switch, during a first half of a retrace interval, to produce a first ramping capacitor voltage in the first capacitor from a portion of a retrace pulse voltage. The first capacitor is coupled to an East-West pincushion raster correction current for producing a second ramping capacitor voltage in the first capacitor that ramps in an opposite direction. A comparator is responsive to the capacitor voltage for controlling a conduction interval of the East-West switching transistor.

Abstract: In a method for controlling color temperature a projection television having green, blue and red image projectors and a projection screen, holographically improving color shift performance of the screen results in an undesirable controlled input angle characteristic that attenuates images projected thereon at horizontal viewing angles of a few degrees from an axis orthogonal to the screen. Projecting blue images along an optical axis orthogonally aligned with the projection screen and projecting green and red along respective optical axes converging toward the orthogonally aligned optical axis makes it possible to energize the blue and green image projectors at substantially equal energy levels when producing a white image on the screen.

Abstract: A screen for a projection-type video display apparatus. A linear-type Fresnel lens has a lens pattern on a first side for receiving light energy from a light source. A second side of the Fresnel lens is opposite the first side. The light energy exits the Fresnel lens from the second side. A hologram is affixed to the second side of the Fresnel lens for managing the dispersion of the light energy exiting from the second side of the Fresnel lens. The hologram is affixed to the Fresnel lens by any of various lamination processes.

Abstract: A projection television comprises a projection screen formed by a three dimensional hologram disposed on a film substrate. A projection tube has an optical path in a substantially orthogonal orientation with the screen and two other projection tubes have respective optical paths converging toward the first optical path at angles of incidence .alpha.. The hologram has a configuration effective for reducing color shift in the displayed images. The screen has a color shift less than or equal to approximately 5 for all angles .alpha., where 0.degree.<.alpha..ltoreq.30.degree., as determined by the maximum value obtained from at least one of the following expressions: ##EQU1## where .theta. is any angle within a range horizontal viewing angles, C(.theta.) is the color shift at angle .theta., red(.theta.) is the red luminance level at angle .theta., blue(.theta.) is the blue luminance level at angle .theta. and green(.theta.) is the green luminance level at angle .theta..