Patent ID: 6034709
Filing Date: 2000-03-07
Classification: G06K

Abstract:
A method for bi-directionally sweeping an electron beam of a monochrome CRT, to illuminate a phosphor area on a face of said monochrome CRT, and to expose a photosensitive medium with light emitted from said face of said monochrome CRT, said method comprising:(a) positioning said electron beam at a first vertical position in said phosphor area on said face of said monochrome CRT;(b) sweeping said electron beam horizontally inside said phosphor area in a forward direction at said first vertical position;(c) modulating said electron beam, during said sweeping of step (b), with a first row of dot row data derived from an image, wherein said first row of dot row data is processed in forward order;(d) exposing a first line of said photosensitive medium during said sweeping and modulating of steps (b) and (c);(e) positioning said electron beam at a second vertical position inside said phosphor area;(f) sweeping said electron beam horizontally inside said phosphor area in a reverse direction at said second vertical position, wherein said reverse direction is opposite said forward direction;(g) modulating said electron beam, during said sweeping of step (f), with a second row of dot row data derived from said image, wherein said second row of dot row data is processed in a reverse order opposite said forward order; and(h) exposing said second line of said photosensitive medium during said sweeping and modulating of steps (f) and (g).