GB712625A - Improvements in or relating to lighting fittings - Google Patents

Abstract

712,625. Lighting fittings. GENERAL ELECTRIC CO., Ltd., and BEGGS, S. S. May 9, 1952 [May 10, 1951], No. 11071/51. Class 75 (2) A lighting fitting for uniformly illuminating an area, e.g. for use in irradiating plants, comprises a concave reflector or pair of concave reflectors arranged to reflect light from a source over an angle of 45 to 120 degrees in a plane, and an auxiliary reflector or reflectors positioned closer to the light source than the outer edge or edges of the concave reflector or reflectors so as to intercept, and re-direct within the desired angle, at least part of the light from the source outside the desired angle and not directed towards the concave reflector or reflectors. A concave reflector 12 is provided at each side of a tubular lamp 10 and is so shaped that rays 20, 22 from the lamp axis 11 are reflected as rays 20<SP>1</SP>, 221 which cross each other at the desired angle of lighting, e.g. 60 degrees. The lower edges of the reflectors 12 extend slightly below the horizontal plane through the axis 11, and for redirecting the rays such as 23 to 26, which are directed below the edges of the reflectors 12 outside the desired angle, two pairs of auxiliary reflectors 15, 16 are provided which produce reflected rays 23<SP>1</SP> to 26<SP>1</SP> within the desired angle. A flat or shallow V-shaped reflecting plate 14 may be provided across the aperture between the upper edges of the reflectors 12 and spaced from the latter to provide passages for the heated air. The visible light source may be replaced by a source of ultra-violet or infra-red radiation. The fitting may, alternatively, comprise a compact light source, and an annular concave reflector.