A vector generator for producing graphic images composed of line segments, having a discrete frequency multiplier 60 which comprises initializing means, stopping means and means for punctuating the drawing of the segments; input means for the M and N components of the segment, and a writing pointer 50...http://www.google.com.tw/patents/US4311998?utm_source=gb-gplus-share專利 US4311998 - Vector generator for a graphic console
