公开(公告)号：US3810166A

公开(公告)日：1974-05-07

申请号：US35714273

申请日：1973-05-04

申请人： ASTON ELECTRONIC DEV LTD

发明人： ATKIN L

IPC分类号： G09G1/12 ,  G09G5/24 ,  G06F3/14

CPC分类号： G09G1/12 ,  G09G5/24

摘要： An electronic system for generating characters for television display by employing selected combinations of analogue waveforms. Ramp waveforms, usually of sawtooth form, are generated at line and field periods and are used to generate in turn triangular and parabolic waveforms. A memory contains data representing the shape of individual elements of characters for each quadrant of a display area and is actuated by a digital store. The memory serves to gate selected combinations of all the waveforms, together with blanking waveforms derived from the triangular waveforms, to synthesize a video character waveform. Means is provided for producing from the video character waveform a further video waveform, defining an area to outline the characters, which acts on a conventional video signal to hold the latter at the black level so that the video character waveform can be inserted thereon.

摘要翻译： 一种用于通过采用所选择的模拟波形的组合来产生用于电视显示的字符的电子系统。 斜坡波形通常是锯齿波形，在线和场周期产生，并用于产生三角波和抛物线波形。