05168351 is referenced by 18 patents and cites 9 patents.

A video color image projector which includes a block of crossed dichroic mirrors for combining the light rays from image rasters on respective monochrome image display devices and a projection lens for projecting the composite color rays so as to form an enlarged color image on a display screen. Each display device has a faceplace which is convex on the interior surface thereof and having thereon an interference filter in the form of an internal angularly reflecting coating (IARC). Each faceplate is liquid - coupled to a negative power lens element, so that the faceplate, coupling liquid (or gel) and such lens element effectively constitute a single negative power field flattener lens at each entrance side of the dichroic block. The composite color rays at the exit side of the dichroic block are projected on the display screen by an assembly of lens elements which includes at least one optically positive lens element. The focal length of the complete projection lens formed by such assembly and each of the negative field flattener lenses may be from 0.5 to 0.9 times the diagonal D of the image raster on each display device, so that the projector is sufficiently compact to be included in a cabinet suitable for consumer television receivers.

Title
Short focal length video color projector employing dichroic mirror block
Application Number
7/523970
Publication Number
5168351
Application Date
May 16, 1990
Publication Date
December 1, 1992
Inventor
Jill F Goldenberg
Pelham Manor
NY, US
William F Guerinot
Knoxville
TN, US
Leendert Vriens
Eindhoven
TN, US
Ralph H Bradley
Kingsport
TN, US
Agent
Leroy Eason
Assignee
North American Philips Corporation
NY, US
IPC
H04N 9/31
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