High intensity short arc lamp having an annular cathode shield

Claim 1

IN AN ELECTRIC DISCHARGE LAMP COMPRISING A LIGHT TRANSMISSIVE CENTRAL GAS CHAMBER DISPOSED BETWEEN END ELECTRODE SECTIONS ONE CONTAINING ANODE COMPONENTS INCLUDING A CONDUCTOR HAVING AN ANODE ELECTRODE DISPOSED WITHIN THE CENTRAL CHAMBER AND THE OTHER CONTAINING CATHODE COMPONENTS INCLUDING A CONDUCTOR HAVING A CATHODE ELECTRODE DISPOSED WITHIN THE CENTRAL CHAMBER AND WHEREIN THE ANODE ELECTRODE AND THE CATHODE ELECTRODE ARE SPACED TO PROVIDE AN ARCING GAP THEREBETWEEN, THE IMPROVEMENT WHICH COMPRISES AN ANNULAR SHIELD WITHIN THE CENTRAL CHAMBER AND EXTENDING FROM THE CENTRAL CHAMBER WALL ADJACENT ONE OF THE ELECTRODE SECTIONS TOWARD THE OTHER ELECTRODE SECTION, SAID SHIELD BEING OF SUFFICIENT LENGTH TO EMBRACE THE ELECTRODE OF THE ONE SECTION AND THE ARCING GAP AND TO POSITION ITS OTHER END IN ALIGNMENT WITH THE TIP END OF THE ELECTRODE OF THE OTHER SECTION AND SAID SHIELD HAVING A DIAMETER TO PROVIDE AN INNER SPACE WITH THE ELECTRODES FOR GAS FLOW AND AN OUTER SPACE WITH THE WALL OF THE CENTRAL CHAMBER FOR SOUND VIBRATIONS.