System for compatible transmission of high-resolution tv

Abstract

A high-resolution television system is described which provides twice the vertical resolution of present television standards and is compatible therewith. A high-resolution television camera substantially simultaneously provides information from each of a pair of adjacent scan lines; the luminance information of both lines is added to provide information for amplitude modulation onto a luminance carrier, while the difference in luminance of the two adjacent scan lines is utilized to modulate a carrier phased in quadrature with the luminance carrier. The chrominance values of both lines are added to modulate a chrominance carrier. The bandwidth of the resulting luminance and chrominance signals are compatible with that of a carrier modulated by a single raster line. At a television receiver, a synchronous quadrature detector provides the sum and difference luminance signals, which are then respectively added to and subtracted from one another to obtain the adjacent line luminance signals for display upon a picture tube in a high-definition television set. A standard television set utilizes only the additive luminance signal to display a compatible picture. Increased horizontal definition, by increasing transmitted signal bandwidth or by utilization of horizontal interlace, and/or increased chroma definition, may be utilized alone or in conjunction with increased vertical resolution to provide a total high-resolution television picture.