CRT video display device with automatically adjustable scanning amplitude

摘要

A cathode ray tube video display device is adapted to display wide aspect ratio signals by reducing the vertical scanning amplitude of the scanning raster. The scan is collapsed in the vertical direction without reducing the number of lines used to display the active picture, leaving unscanned bands at the top and bottom of the display. The device can change between a normal raster scanning mode and such a collapsed wide screen mode automatically in response to an indicator in the received video signal.