GB463853A - Improvements in cathode glow lamps - Google Patents

Abstract

463,853. Discharge lamps ; television. GENERAL ELECTRIC CO., Ltd. Aug. 14, 1936, No. 22416. Convention date, Aug. 31, 1935. [Classes 39 (i) and 40 (iii)] A cathode glow lamp, in or for a television receiver adapted to receive a carrier modulated at a frequency exceeding 100 kcs., has a filling of which the main constituents are neon and helium, the proportion of helium exceeding 50 per cent. A mixture of 70 per cent helium and 30 per cent neon may be employed, with optional addition of argon, nitrogen or water vapour. Water vapour may be obtained from copper sulphate within the envelope. Better response to high frequency modulation is obtained compared with the more usual mixtures containing 75 per cent neon. In the lamp shown the cathode 6 is a metal sheet bent at an angle of 20‹-50‹ and the anode 9 has a central slot 13 and flanged edges 10. The glow at the apex of the cathode proceeding through the slot 13 produces a line of light suitable for use with a mirror screw. A sheet of mica. 14 covers the outside of the cathode. The electrodes are spaced by wires and glass beads and are supported at one end by a pinch and at the other by a wire engaging a depression in the envelope. British Specification 145,400, [Class 39 (i)], and U.S.A. Specification 1,832,009 are referred to.