Modulation system for cathode ray tubes

Claim 1

IN AN ELECTRON DISCHARGE DEVICE HAVING AN ELECTRON GUN OPERATIVE TO EMIT AN ELECTRON BEAM AND INCLUDING IRIS MEANS WITH THE CROSS-OVER POINT OF THE ELECTRON BEAM NORMALLY LOCATED WITHIN THE APERTURE THEREOF, AN INTENSITY MODULATING SYSTEM FOR SAID BEAM COMPRISING MEANS FOR PRODUCING AN ELECTRON BEAM WITH A PREDETERMINED CROSS SECTION INCLUDING FIRST AND SECOND DIAPHRAGM MEANS PROVIDED WITH APERTURE MEANS FOR THE PASSAGE OF THE ENTIRE PREDETERMINED CROSS SECTION OF THE UNMODULATED ELECTRON BEAM, AND MODULATING MEANS FOR INTENSITY MODULATING SAID BEAM IN SUCH A MANNER THAT THE INTENSITY OF SAID BEAM VARIES PROPORTIONALLY AND LINEARILY WITH THE AMPLITUDE OF THE APPLIED MODULATING SIGNALS INCLUDING DEFLECTION MEANS FOR DEFLECTING SAID BEAM IN SUCH A MANNER THAT THE NUMBER OF ELECTRONS PASSING THROUGH SAID APERTURE MEANS VARIES SUBSTANTIALLY LINEARLY IN ACCORDANCE WITH THE AMPLITUDE OF THE MODULATING SIGNALS APPLIED TO SAID DEFLECTING MEANS MODULATING SIGNALS APPLIED TO SAID DEFLECTING MEANS AND CORRECTING MEANS OPERATIVELY ASSOCAIATED WITH SAID DEFLECTION MEANS TO MAINTAIN SAID CROSS OVER POINT SUBSTANTIALLY COINCIDENT WITH THE AXIS OF THE TUBE AT A POINT ADJACENT SAID IRIS MEANS.