New Color Video Projection System with Glass Optics and Three Primary Color Tubes for Consumer Use

Approximately forty years ago, the first commercial video projection system was introduced. Until quite recently all projection systems were designed for institutional use only. In 1972, however, the Sony Corporation unveiled a projection system1) for consumer use at the International Convention and Exposition sponsored by IEEE. Since that time, as the quality of large-screen pictures improved, and their price fell, the many advantages of a large-screen picture over a conventional color TV picture have created a new consumer electronics market. The development of a projection system for consumer use has been made possible by recent advances in cathode-ray tube and electronic circuit technology. In addition to these essential advances, many new techniques have been developed in, for instarnce, projection optics and screen fabrication.