Light distributor for proximity printer - is raster of prisms of polyhedrons selected to scatter light and eliminate shadows

摘要

In a proximity printer, the light source is made multiple, to eliminate shadows and interference patterns. This is done by putting a screen (preferably of polyhedra, prisms or truncated prisms) in the path of a concentrated source of light, so as to split the beam into rays shining in all directions. The spacing and angles of the polyhedra, etc. are chosen to this end. The assembly comprises a light source (1), concentrating lenses (2, 3), screen of polyhedra etc. (4), original assembly for copying (5) and sub-layer onto which the copy is being made (6). The lenses are both convergent types and typically each plano-convex with the outer surfaces being the plane ones in each case.