Method for making u-v responsive photoemissive tubes

Claim 1

A METHOD FOR MAKING A U-V RESPONSIVE, SEMI-TRANSPARENT CATHODE IN A PHOTOEMISSIVE TUBE HAVING A U-V TRANSMITTING SECTION OF MATERIAL, AT LEAST ONE SIDE OF SAID SECTION BEING INTERNAL TO SAID TUBE, COMPRISING THE STEPS OF: EVACUATING SAID TUBE; SUBJECTING SAID TUBE TO A DEGASSING BAKE OF APPROXIMATELY 350-400 DEGRES CENTRIGRADE; DEPOSITING A LAYER OF CONDUCTIVE MATERIAL ON THE INTERNAL SIDE OF SAID U-V TRNASMISTING SECTION: HALTING SAID DEPOSITION WHEN THE VISIBLE LIGHT TRANSMITTED THROUGH SAID LAYER OF CONDUCTIVE MATERIAL AND SAID U-V TRANSMITTING SECTION IS APPROXIMATELY 85-90% OF THE VISIBLE LIGHT TRANSMITTED THROUGH SAID U-V TRANSMITTING SECTION ALONE; DEPOSITING A LAYER OF TELLURIUM UPON SAID LAYER OF CONDUCTIVE MATERIAL BY HEATING A COMPOUND CONSISTING OF TELLURIUM AND AN ELEMENT, SUCH AS INDICUM, HAVING A LOWER VAPOR PRESSURE, THE DECOMPOSITION TEMPERATURE OF SAID COMPOUND BEING HIGHER THAN THAT OF SAID DEGASSING BRAKE; HALTING DEPOSITION OF SAID LAYER OF TELLURIUM WHEN THE VISIBLE LIGHT TRANSMITTED BY SAID U-V TRANSMITTING SECTION AND SAID LAYERS OF CONDUCTIVE MATERIAL AND TELLURIUM IS APPROXIMATELY 3% LOWER THAN THAT OF ONY SAID U-V TRANSMITTING SECTION AND SAID LAYER OF CONDUCTIVE MATERIAL; EVAPORATING AN ALKALI METAL SO THAT ITS VAPOR COMBINES WITH SAID TELLURIUM LAYER TO FORM AN ALKALI TELLURIDE COMPOUND; AND HALTING SAID EVAPORATION OF SAID ALKALI METAL WHEN THE EMISSION CURRENT OF SAID PHOTOEMISSIVE TUBE, AS GENERATED BY U-V LIGHT PASSED THROUGH SAID TRANSMITTING SECTION AND INCIDENT UPON SAID ALKALI TELLURIDE LAYER, IS APPROXIMATELY AT ITS MAXIMUM VALVE.

Claim 2

A METHOD FOR MAKING A U-V RESPONSIVE, SEMI-TRANSPARENT CATHODE IN A PHOTOEMISSIVE TUBE HAVING A U-V TRANSMITTING SECTION OF MATERIAL, AT LEAST ONE SIDE OF SAID SECTION BEING INTERNAL TO SAID TUBE, COMPRISING THE STEPS OF: EVACUATING SAID TUBE; SUBJECTING SAID TUBE TO A DEGASSING BAKE OF APPROXIMATELY 350-400 DEGRES CENTRIGRADE; DEPOSITING A LAYER OF CONDUCTIVE MATERIAL ON THE INTERNAL SIDE OF SAID U-V TRNASMISTING SECTION: HALTING SAID DEPOSITION WHEN THE VISIBLE LIGHT TRANSMITTED THROUGH SAID LAYER OF CONDUCTIVE MATERIAL AND SAID U-V TRANSMITTING SECTION IS APPROXIMATELY 85-90% OF THE VISIBLE LIGHT TRANSMITTED THROUGH SAID U-V TRANSMITTING SECTION ALONE; DEPOSITING A LAYER OF TELLURIUM UPON SAID LAYER OF CONDUCTIVE MATERIAL BY HEATING A COMPOUND CONSISTING OF TELLURIUM AND AN ELEMENT, SUCH AS INDICUM, HAVING A LOWER VAPOR PRESSURE, THE DECOMPOSITION TEMPERATURE OF SAID COMPOUND BEING HIGHER THAN THAT OF SAID DEGASSING BRAKE; HALTING DEPOSITION OF SAID LAYER OF TELLURIUM WHEN THE VISIBLE LIGHT TRANSMITTED BY SAID U-V TRANSMITTING SECTION AND SAID LAYERS OF CONDUCTIVE MATERIAL AND TELLURIUM IS APPROXIMATELY 3% LOWER THAN THAT OF ONY SAID U-V TRANSMITTING SECTION AND SAID LAYER OF CONDUCTIVE MATERIAL; EVAPORATING AN ALKALI METAL SO THAT ITS VAPOR COMBINES WITH SAID TELLURIUM LAYER TO FORM AN ALKALI TELLURIDE COMPOUND; AND HALTING SAID EVAPORATION OF SAID ALKALI METAL WHEN THE EMISSION CURRENT OF SAID PHOTOEMISSIVE TUBE, AS GENERATED BY U-V LIGHT PASSED THROUGH SAID TRANSMITTING SECTION AND INCIDENT UPON SAID ALKALI TELLURIDE LAYER, IS APPROXIMATELY AT ITS MAXIMUM VALVE.