Reflector for use in an artificial lighting device

DETAILED DESCRIPTION I claim: 1.
An artifical lighting assembly comprising: an artifical source of illumination having spherical geometry; a concave, open-ended reflector that is rotationally symmetric about a given axis and has a cross-sectional shape in the form of a 7th order polynomial curve given by the equation: ##EQU4## where Y and X are, respectively, the dependent and independent variables in a Cartesian coordinate system and the terms, A.
sub.
n, represent the coefficients of said polynomial and are nonzero for the first through seventh order terms, said polynomial curve having a radius of curvature, and hence optical power, which progressively changes in a gradual manner without discontinuities with distance along said curve, said curve being shaped so that the radius of curvature thereof increases with increasing distance from the apex thereof so as to reduce the optical power of said reflector in accordance with increasing distance along said curve; and means for positioning said source within said reflector in a predetermined manner to project a beam of illumination of predetermined solid angle that is rotationally symmetric about said reflector axis of symmetry to illuminate any plane normal to said reflector axis of symmetry, spaced ahead of said assembly and within said beam angle of divergence and effective range, in a substantially uniform manner over another solid angle that is smaller than said solid angle of said beam of illumination, said reflector operating to reflect light from said source in a manner whereby the intensity of the light reflected from said reflector progressively increases in a gradual manner, without discontinuities, in accordance with increasing angular divergence of light rays within said beam as measured away from said reflector axis of symmetry such that the intensity of illumination of points on any normal plane, which points are spaced away from said reflector axis of symmetry, is increased to compensate substantially exactly for natural losses in direct illumination from said source which would otherwise be present at those same points absent said reflector and to abruptly cause a reduction in the intensity of the illumination of light traveling at angles, as measured with respect to said axis of symmetry, which are greater than said other smaller solid angle