GB450513A - Means for observing the image produced by x-rays on a fluorescent screen - Google Patents

Abstract

450,513. Coloured glass. SOC. ANON. DES MANUFACTURES DES GLACES ET PRODUITS CHIMIQUES DE ST.-GOBAIN, CHAUNY, & CIREY, 1<bis>, Place des Saussaies, Paris. Jan. 15, 1935, No. 1384. Convention date, Jan. 16, 1934. [Class 56] [See also Group XX] Means for facilitating the observation of images produced by X-rays on a fluorescent screen in a room lighted by a sodium vapour lamp comprises the combination with the fluorescent screen of a neodymium oxide glass filter arranged so that the filter is between the observer and the screen, whereby while radiation from the lamp is absorbed by the filter, the major part of the radiation from the fluorescent image is transmitted by the filter. The proportion of neodymium oxide in the glass of the filter may vary between 2 and 12 per cent when fluorescent screens of barium platino cyanide or tungstate of cadmium or calcium are used. With the filter screen may be used a screen, as of glass containing oxides of lead and barium, which prevents harmful X-rays transmitted by the fluorescent screen from reaching the eye of the observer ; and such screen may be combined with the filter screen, as by using a single glass screen containing all the oxides mentioned, e.g. 45 per cent lead oxide, 15 per cent barium oxide and 5 per cent neodymium oxide.