DISPLAY SYSTEM WITH MAJOR AND MINOR RASTER SCANS

摘要

A cathode ray tube display system is provided for displaying a block comprising a plurality of alphanumeric characters arranged in a plurality of character lines having cyclic refresh means wherein each unitary or whole character is refreshed before the next succeeding character is refreshed. The system comprises means for repetitive raster scanning of the CRT tube in a raster of horizontal passes each traversing the whole one of said character; each of these horizontal passes comprises a subraster of vertical scan lines wherein each character position in said character line being traversed is scanned by a group of these vertical scan lines, and means are provided for modulating the light intensity along the vertical scan lines of each of these groups to selectively provide an alphanumeric character at the position being scanned by the group of scan lines.