GB281030A - Improvements in advertising and signalling devices - Google Patents

Abstract

281,030. Harris, H. K. Sept. 9, 1926. Monogrammic signs. -Relates to devices of the type in which the elements or surfaces are coated with or carry fluorescent, phosphorescent, or radio-active substances, and consists in combining such surfaces with a source of visible or invisible light so that the point of incidence of the light is movable relatively with respect to the surfaces or elements. The element or surface is preferably constructed of glass, porcelain &c. and is divided up by separating walls a into shallow cells b which hold the fluorescent substance. The element is closed with a cover d of glass, quartz, &c. A metal casing c may encircle the element and retain the parts in position by a spun over flange f. Large surfaces or plaques may be prepared and light projected on them through a slide screen or mask relatively immovable with respect to the surface during the existing action and in this manner letters, &c. may be produced. A beam of visible or invisible rays, ultra-violet or X-rays may be emitted from a projector which is movable according to a predetermined path. After the substance has been exposed and excited by light rays of a suitable wave length, and has been exhibited, its luminosity may be extinguished by exposing it to light of a different and selected wave length according to the substance used.