Adjustable reflector device

A reflector device for a luminaire, said reflector device comprising a pair of resilient sheets positioned one to either side of a spine in the manner of the pages of a book, said sheets when in an unbiased condition lying substantially in two planes intersecting at an obtuse angle and when flexed and retained against the bias of their normal resilience having a doubly arched configuration which forms a reflective surface, said sheets being retained in said doubly arched configuration by a retainer which extends between opposite sides of said doubly arched configuration and is adjustable in length.

A luminaire having an adjustable reflector and an elongate light source to emit a beam of light of adjustable beam geometry, said reflector having a doubly arched configuration formed by two resilient wings located one to either side of a central region and arched into a substantially symmetrical m-shaped configuration having a longitudinally extending axis of symmetry and two concave reflective surfaces wherein said wings have substantially parallel outer extremities, said light source is arranged adjacent said concave surfaces and is both spaced apart from, and substantially parallel to, said axis of symmetry whereby light from said light source is incident on each of said concave surfaces substantially equally, and whereby the curvature of said concave reflective surfaces is simultaneously and equally adjustable by adjusting the distance between said outer extremities and said luminaire further comprising at least one elongate retainer each of which extends between the outer extremity of one wing to the outer extremity of the other wing to retain said concave reflective surfaces at a predetermined selected one of a plurality of possible curvatures each of which results in a different geometry of the beam of light emitted from said luminaire.

A method of adjusting the radiant intensity of a luminaire having a resilient doubly-arched reflective surface formed from a pair of sheets positioned one to either side of a spine in the manner of the pages of a book, the sheets when in an unbiased condition lying substantially in two planes intersecting at an angle and extending from the spine to free edges, said method comprising the steps of flexing said sheets against the bias of their normal resilience creating said doubly-arched configuration wherein said free edges are spaced from to one another, and connecting a retainer between said free edges which is detachable from and reattachable to at least one of said free edges to adjust the spacing of said free edges and thus the degree of flexure of said sheets thereby to select the curvature of said doubly-arched reflective surface.

A method of making a reflector device for a luminaire comprising the steps of forming a pair of flat, flexible, resilient reflective sheets which extend away from a rigid central spine to free edges and which define an obtuse angle, flexing the sheets away from the spine so as to widen said angle and form a pair of arched reflective surfaces on opposite sides of the spine which extend from the spine to said free edges, and connecting the free edges together by a retainer which is detachable from and then reattachable to at least one of said free edges so as to maintain a selected one of a plurality of possible distances between them.

A method of making a reflector device for a luminaire comprising the steps of forming a pair of flat, flexible, resilient reflective sheets which extend away from a rigid central spine to free edges and which define an obtuse angle, flexing the sheets away from the spine so as to widen said angle and form a pair of arched reflective surfaces on opposite sides of the spine which extend from the spine to said free edges, connecting the free edges together and adjusting the distance between said free edges so as to change the curvature of said reflective surfaces.