GB474141A - Improvements in and relating to luminairs - Google Patents

Abstract

474,141. Street &c. lamps. HOLOPHANE, Ltd. (Rolph, T. W.) April 5, 1937, No. 9623. [Class 75 (ii)] In a street or like lamp in which a symmetrical or asymmetrical reflector 13 above the light source 12 redistributes the light in vertical planes and directs it downwardly into an opentopped bowl or band refractor 14 which surrounds the light source and redistributes the light in horizontal planes, the refractor is supplemented by an internal deflector which intercepts some of the direct and reflected light and diverts it away from the eclipsed portion of the refractor to augment the asymmetrical distribution of the light. The deflector may be prismatic and formed on one or both surfaces with refracting prisms arranged vertically and/or horizontally, diagonally, or in concentric arcs, or it may be made reflecting by using reflecting prisms or specular or diffuse reflecting surfaces such as polished metal, silvered glass, porcelain enamel, opal glass, or plastic material. When the deflector is opaque it may be spaced away from the refractor so that some direct or reflected light may pass behind the deflector to illuminate the eclipsed portion of the refractor. The deflector may be flat or curved, and it may be disposed vertically or inclined. A pair of similar or dissimilar deflectors may be arranged one on each side of the light source. Fig. 2 shows a deflector 17 with vertical refracting prisms fitted into a slot 27 in the refractor 14 so as to augment the lateral deviation of the light. Fig. 4 shows a deflector 32 with horizontal refracting prisms to augment the downward deviation of the light. Fig. 8 shows a cylindrical deflector 40 formed with reflecting prisms for directing the light towards the opposite side of the refractor. Fig. 10 shows a pair of deflectors 49, 50 fitted into an elliptical refractor 14.