Character display cathode ray tube

Claim 1

IN A CATHODE-RAY DISPLAY TUBE, APPARATUS OF THE CHARACTER DESCRIBED, COMPRISING: A SOURCE OF ELECTRONS INCLUDING A CATHODE HAVING AN ELECTRON EMISSIVE SURFACE; A GRID HAVING ALTERNATE SOLID PORTIONS AND OPENINGS, SAID GRID BEING LOCATED ADJACENT SAID CATHODE SURFACE, THE RATIO OF THE WIDTH OF THE SOLID PORTIONS OF THE GRID TO THE SPACING THEREBETWEEN BEING AT LEAST 0.05 AND LESS THAN 0.5 AND THE RATIO OF THE SPACING BETWEEN THE SOLID PORTIONS OF THE GRID TO THE SPACING OF THE GRID FROM THE EMISSIVE CATHODE SURFACE BEING AT LEAST 2.1 AND LESS THAN 10, WHEREBY A VOLTAGE APPLIED BETWEEN THE GRID AND CATHODE ESTABLISHES A VARYING VOLTAGE GRADIENT ACROSS THE EMISSIVE SURFACE OF THE CATHODE TO CONTROL THE EMISSION OF ELECTRONS THEREFROM AND TO FORM SAID ELECTRONS INTO A PLURALITY OF DISCRETE BEAMS WHICH COMPRISE A BUNDLE OF ELECTRON BEAMS; AND MEANS FOR MASKING A PORTION OF SAID BUNDLE OF ELECTRON BEAMS TO GIVE THE BUNDLE A DESIRED CROSS-SECTIONAL CONFIGURATION.