A method and apparatus for producing a light source of required shape.

摘要

Apparatus for producing a light source of a desired shape from a light source such as a laser comprising means for directing the light source along a predetermined path 10 as a playback beam to impinge upon a hologram 12 at a predetermined angle to produce the continuous self-luminous source of the desired shape. The hologram is recorded upon a substrate 28 coated with a photosensitive material 30 by interference between recording and object beams 24, 48 derived from the same source 20 of coherent radiation. The recording beam 24 is directed toward the substrate at an orientation and angle so that the playback beam 10 is a conjugate of the recording beam. The object beam 48 is directed to the substrate 28 over a path which includes a diffuser plate 36 covered with an opaque material in all areas except for a continuous area which defines the desired shape. The part of the object beam which impinges upon the substrate is limited by a stop 17 which defines the numerical aperture.