Liquid hollow cathode lamp

Claim 1

IN A HOLLOW CATHODE LAMP OF THE TYPE IN WHICH THE HOLLOW CATHODE COMPRISES AT LEAST ONE PARTICULAR METAL FOR WHICH SPECTRAL LINES ARE DESIRED, SUCH LAMPS BEING ESPECIALLY ADAPTED FOR USE IN ATOMIC ADSORPTION SPECTROSCOPY, THE IMPROVEMENT COMPRISING: SAID HOLLOW CATHODE BEING OF GENERALLY CUP SHAPE, WITH THE WALLS DEFINING ITS INTERIOR HAVING GENERALLY INTURNED WALL PORTIONS ADJACENT TO THE OPEN END THEREOF; A THIN COATING OF SAID PARTICULAR DESIRED METAL SUBSTANTIALLY COVERING THE ENTIRE INTERIOR SURFACE OF SAID WALLS AT LEAST UP TO SAID-IN-TURNED END PORTIONS, SAID PARTICULAR DESIRED METAL HAVING A MELTING POINT BELOW THE NORMAL OPERATING TEMPERATURE OF SAID LAMP, BUT HAVING A BOILING POINT SUBSTANTIALLY ABOVE SAID TEMPERATURE AND A RELATIVELY LOW VAPOR PRESSURE THEREAT; SAID IN-TURNED END PORTIONS OF SAID WALL THEREBY INHIBITINH LOSS OF LIQUID METAL COATING DURING OPERATION OF SAID LAMP; WHEREBY RELATIVELY HIGH INTENSNITY RADIATION AT THE SPECTRAL EMISSION-ABSORPTION LINES OF SAID PARTICULAR DESIRED METAL IS OBTAINED.