公开(公告)号：US3597533A

公开(公告)日：1971-08-03

申请号：US3597533D

申请日：1968-08-21

Applicant: INT COMPUTERS LTD

Inventor： HUGHES GORDON

IPC: G09G1/22 ,  H04N3/32 ,  H04N5/14 ,  H04N5/38

CPC classification number: H04N3/32 ,  G09G1/22

Abstract: A system for high-speed scanning of graphical symbols in which a line is scanned by a first waveform at a first speed and upon the scan passing over the leading or trailing edge of a symbol, an output is developed and applied to a pulse generator. The pulse generator produces a substantially rectangular pulse whenever the scan passes a leading or trailing edge of a symbol portion, while the pulses are integrated by an appropriate amplifier. The integrated pulses form a second triangular-shaped waveform which is combined with the first scanning waveform such that the scan speed of the first waveform is temporarily reduced below normal scan speed and is temporarily increased above normal scan speed before reaching and remaining at a normal speed. The combined scanning waveform is then transmitted to a display device along with the first waveform and appropriate control signals such that the symbol scanned may be remotely displayed.