Patent ID: 6167646
Filing Date: 2001-01-02
Classification: A61B,G02B

Abstract:
Apparatus for illuminating medical diagnostic imaging film comprising: means for supporting said imaging film in a specified plane; means for projecting light having a first solid angle and comprising first and second light portions toward said film support means, said first and second light portions including light rays directed at angles relative to said specified plane which are respectively greater than, and less than, a critical angle; light directing film means positioned between said light projecting means and said film support means for converging said first light portion to lie within a second solid angle which is substantially less than said first solid angle, said converged light directed toward said specified plane to illuminate said imaging film, said light directing film means further comprising means for selectively directing said second light portion away from said specified plane, said light directing film means comprising a plurality of layers of microprism film; and each of said microprism film layers comprises a number of rows of microscopic prism elements, the rows of one of said layers being oriented in non-parallel relationship with the rows of another one of said layers.