Display and projection devices for HDTV

A 50 in rear projection display for consumer use and a 180 in front projection display for video theatres and other extra-large display applications are discussed. The 50 in display uses an optical coupling system. The contrast ratio has been more than doubled to a level approximately equivalent to that of a CRT, and resolution has been increased, owing to improvements in the screen, to 1000 TV lines. The TV set depth is 65 cm as a result of a reduced projection distance, and peak luminance is 120 ft-L, double that of conventional designs. For the 180 in display the development of a 12 in liquid-cooled projection tube allows high beam current loading, providing a light output approximately twice that of conventional designs and realizing a peak luminance of 15 ft-L, equivalent to that of a movie screen. Its contrast ratio has also been greatly improved with the optical coupling system. The projection lens is also newly developed and is compatible for use with 150 in to 250 in screens.<
>