Improved 625 Line Systems

Abstract

It is less than 60 year ago stated that future TV services should be “high definition” i.e. have a quality of at least 240 lines and 24 pictures per second. HDTV seems not to be an absolute indication of the picture quality but much more a relative one. The picture quality, which is of course, when television SYSTEMS are being discussed, the quality of the picture in the viewers home, has steadily increased in the past. Thereby the viewing distance remained remarkebly constant. Also the perce.ived sharpness in terms of number of cycles per viewing angle did not change a lot and although often complaints are heard from the public about the picture material offered to them, these complaints seldom concerned the picture sharpness. All improvements in camera- and display-technology that allowed more pixels on the display, were used to increase the size of the display. This trend, however, seems to have come to an unnatural end and that is because we almost have reached the point that the transmission standard has become the a limiting factor that blocks the further gradual improvement of television.