Adjustable luminaire

Claim 1

An improved luminaire for use with high intensity discharge lamps, the luminaire being of the type having a housing, a mounting bracket coupled to said housing, lamp mounting means on said housing for receiving a lamp with the central axis of the lamp in a predetermined relationship to said mounting means and housing and an open-ended reflector attached to said housing, said housing being angularly adjustable relative to said mounting bracket to thereby adjust the inclination of the axis of said lamp, the improvement wherein said reflector has a wall formed such that the interior reflective surface thereof defines first and second distinct surfaces of revolution which are different from each other, each surface occupying about one-half of the internal circumference of the reflector, the two surfaces being separated by transition regions extending from said means for attaching to said open end, said first of said surfaces comprising a parabola having a central axis at an angle of about 54° relative to the longitudinal axis of said lamp; and said second of said suraces following an elliptical surface of revolution having one focus at the center of said lamp, said second of said surfaces being fluted; and wherein said reflector further comprises means defining an opening in said reflector through which a lamp can extend from said lamp mounting means into said reflector; and means around said opening for attaching said reflector to said lamp mounting means.