Radiographic systems and method

Claim 1

A SYSTEM FOR SELECTIVELY PRODUCING CONVENTIONAL RADIOGRAPHIC EXPOSURES UTILIZING RELATIVELY LARGE FOCAL SPOTS PRODUCED AT THE ANODE OF AN X-RAY TUBE AND CINERADIOGRAPHIC EXPOSURES UTILIZING RELATIVELY SMALL FOCAL SPOTS PRODUCED IN THE SAME TUBE, COMPRISING A FIRST FILAMENT AND A SECOND FILAMENT MOUNTED IN SPACED RELATION IN SAID TUBE, SWITCHING MEANS IN THE X-RAY TUBE COMPRISING A CONDUCTIVE FIELD-FORMING ELEMENT WITHIN WHICH THE FILAMENTS ARE RECESSED, POWER SUPPLY MEANS FOR THE FILAMENTS, MEANS FOR SUPPLYING A NEGATIVE BIAS POTENTIAL TO THE SWITCHING MEANS FOR CREATING A NEGATIVE FIELD AT SAID FIRST FILAMENT FOR SUPPRESSING ELECTRON FLOW THEREFROM, MEANS FOR PRODUCING A VOLTAGE PULSE HAVING A POTENTIAL SUFFICIENT TO OVERCOME THE NEGATIVE POTENTIAL ON THE SWITCHING MEANS AND FOR TRANSMITTING SUCH A SQUARE PULSE TO THE SWITCHING MEANS TO OVERCOME SAID NEGATIVE POTENTIAL WHEREBY THE FIRST FILAMENT IS PERMITTED TO GIVE OFF A STREAM OF ELECTRONS AND CONTROL MEANS CONNECTED WITH SAID POWER SUPPLY MEANS FOR THE FILAMENTS FOR SIMULTANEOUSLY DISCONNECTING SAID FIRST FILAMENT FROM THE POWER SUPPLY MEANS, REMOVING POTENTIAL FROM SAID SWITCHING MEANS, AND CONNECTING THE SECOND FILAMENT TO THE POWER SUPPLY MEANS, SAID CONTROL MEANS COMPRISING A FIRST CONDUCTOR CONNECTING ONE SIDE OF EACH OF THE FILAMENTS TO SAID POWER SUPPLY MEANS, A SECOND CONDUCTOR CONNECTING THE POWER SUPPLY MEANS TO THE OTHER SIDE OF THE FIRST FILAMENT, A THIRD CONDUCTOR CONNECTED AT ONE END TO THE POWER SUPPLY MEANS AND AT ITS OTHER END TO A CONTACT IN A FIRST RELAY WHICH IS CONNECTED ACROSS THE FIRST AND SECOND CONDUCTORS, THE ARMATURE OF SAID RELAY BEING CONNECTED BY A LEAD TO THE SWITCHING MEANS, A SECOND RELAY IN SAID SECOND CONDUCTOR AND HAVING AN ARMATURE CONNECTED TO SAID LEAD AND HAVING A CONTACT CONNECTED BY A LEAD TO THE SECOND FILAMENT, THE NEGATIVE BIAS CIRCUIT BEING CONNECTED BETWEEN A SECOND CONTACT IN SAID FIRST RELAY AND SAID FIRST CONDUCTOR, AND A SWITCH CONNECTED TO THE POWER SUPPLY MEANS FOR SELECTIVELY CONNECTING THE POWER SUPPLY MEANS TO THE FIRST AND SECOND CONDUCTORS AND TO THE FIRST AND THIRD CONDUCTORS.

Claim 2

A SYSTEM FOR SELECTIVELY PRODUCING CONVENTIONAL RADIOGRAPHIC EXPOSURES UTILIZING RELATIVELY LARGE FOCAL SPOTS PRODUCED AT THE ANODE OF AN X-RAY TUBE AND CINERADIOGRAPHIC EXPOSURES UTILIZING RELATIVELY SMALL FOCAL SPOTS PRODUCED IN THE SAME TUBE, COMPRISING A FIRST FILAMENT AND A SECOND FILAMENT MOUNTED IN SPACED RELATION IN SAID TUBE, SWITCHING MEANS IN THE X-RAY TUBE COMPRISING A CONDUCTIVE FIELD-FORMING ELEMENT WITHIN WHICH THE FILAMENTS ARE RECESSED, POWER SUPPLY MEANS FOR THE FILAMENTS, MEANS FOR SUPPLYING A NEGATIVE BIAS POTENTIAL TO THE SWITCHING MEANS FOR CREATING A NEGATIVE FIELD AT SAID FIRST FILAMENT FOR SUPPRESSING ELECTRON FLOW THEREFROM, MEANS FOR PRODUCING A VOLTAGE PULSE HAVING A POTENTIAL SUFFICIENT TO OVERCOME THE NEGATIVE POTENTIAL ON THE SWITCHING MEANS AND FOR TRANSMITTING SUCH A SQUARE PULSE TO THE SWITCHING MEANS TO OVERCOME SAID NEGATIVE POTENTIAL WHEREBY THE FIRST FILAMENT IS PERMITTED TO GIVE OFF A STREAM OF ELECTRONS AND CONTROL MEANS CONNECTED WITH SAID POWER SUPPLY MEANS FOR THE FILAMENTS FOR SIMULTANEOUSLY DISCONNECTING SAID FIRST FILAMENT FROM THE POWER SUPPLY MEANS, REMOVING POTENTIAL FROM SAID SWITCHING MEANS, AND CONNECTING THE SECOND FILAMENT TO THE POWER SUPPLY MEANS, SAID CONTROL MEANS COMPRISING A FIRST CONDUCTOR CONNECTING ONE SIDE OF EACH OF THE FILAMENTS TO SAID POWER SUPPLY MEANS, A SECOND CONDUCTOR CONNECTING THE POWER SUPPLY MEANS TO THE OTHER SIDE OF THE FIRST FILAMENT, A THIRD CONDUCTOR CONNECTED AT ONE END TO THE POWER SUPPLY MEANS AND AT ITS OTHER END TO A CONTACT IN A FIRST RELAY WHICH IS CONNECTED ACROSS THE FIRST AND SECOND CONDUCTORS, THE ARMATURE OF SAID RELAY BEING CONNECTED BY A LEAD TO THE SWITCHING MEANS, A SECOND RELAY IN SAID SECOND CONDUCTOR AND HAVING AN ARMATURE CONNECTED TO SAID LEAD AND HAVING A CONTACT CONNECTED BY A LEAD TO THE SECOND FILAMENT, THE NEGATIVE BIAS CIRCUIT BEING CONNECTED BETWEEN A SECOND CONTACT IN SAID FIRST RELAY AND SAID FIRST CONDUCTOR, AND A SWITCH CONNECTED TO THE POWER SUPPLY MEANS FOR SELECTIVELY CONNECTING THE POWER SUPPLY MEANS TO THE FIRST AND SECOND CONDUCTORS AND TO THE FIRST AND THIRD CONDUCTORS.