Television that conveys real-time information has become an indispensable part of our lives. Its technology has advanced from the days of black-and-white sets to color models and to high-definition television (HDTV). HDTV has been contrived to provide the audience with greater immediate appeal such as sensation of reality and power than the current TV system does and its worldwide applications are expected to continue to grow. Real world information which we obtain with our eyes is three-dimensional. It is reasonable therefore, that we humans want an imaging system that produces pictures that are as natural and real as things we see and experience every day. Three-dimensional television (3DTV) is a very promising approach expected to satisfy such wishes. As television technology matures and HDTV produces pictures as clear as movies, 3DTV is now capable of providing real-time stereoscopic pictures with high resolution. This paper outlines the studies that have been carried out about 3DTV as a post-HDTV system. The themes of the paper are focused to such topics as human factors in relation to binocular parallax, camera and display systems, and bandwidth reduction technology.>

A laser communication system, which has an automatic acquisition and tracking capability without the aid of any other communication link, has been constructed and experimented. It consists of two terminals that can transmit one TV signal and error signals for tracking each other. The heart of this system is a combination of a laser, a position sensor, an angle detector, and an optical deflector that can send back a laser beam parallel to an incident beam as if it were a retroreflector. The availability of this system was proved from a transmission experiment at the distance of 500 m. The maximum propagation distance of this system is estimated to be 1 km if a 200-mm diameter receiving aperture is used, even though there are spot dancing and beam spreads.