GB415111A - Improvements in and relating to electric luminous discharge tubes - Google Patents

Abstract

415,111. Discharge lamps. ROTHER, F., 6, Bozenerstrasse, Sch÷neberg, Berlin. Jan. 18, 1933, No. 1724. Convention date, Jan. 18, 1932. Drawings to Specification. [Class 39 (i).] In a discharge lamp provided with two or more gases or vapours and with electrodes which are visible and are not heated by an auxiliary source of current, the partial pressure of one component of the filling is equal to or less than 6 mms. and that of the other component is greater than 6 mms., e.g. 10 to 30 mms., and the respective pressures are adjusted so that the former component emits a brilliant radiation in one colour between the electrodes, and the latter component covers one or both of the electrodes with a brilliant glow in a different colour. The components may each consist of one or more rare or non- rare gases or metal vapours and the constituents of the former component, preferably, have the same partial pressures. The filling may consist of argon at 6 mms. and of neon at 10 to 20 mms. to which a drop of mercury may be added. The electrodes, which may form signs &c., consist of wires, plates or of sheet-iron cylinders. To facilitate starting the electrodes may be formed of radiactive metal or alloy, such as an alloy of molybdenum and thorium, or by coating a metal with another metal which is situated in the periodic table on the left of, or on the left of and in a line lower than that of, the core metal, e.g. tungsten may be coated with thorium, iron with tin or barium, and chromium with beryllium. The position of the electrodes may be adjusted so that the lamp will operate at a voltage of 110. In a modification, the electrodes consist of mercury, the vapour of which forms the component having a pressure of less than 6 mms. and the lamp may be operated by continuous or alternating current.