Patent ID: 7125131
Filing Date: 2006-10-24
Classification: G02B

Abstract:
1. An optical substrate comprising: a surface comprising a prism structure characterized by a cross section having a curved facet described by the equation wherein z is the perpendicular deviation of the surface of the facet of the prism from a straight line originating at a first reference point and terminating at a second reference point and the coefficients of the polynomial lie within the following approximate ranges: −20 <c <20; −10 <d <10; −10 <e <10; −10 <f <10 and −1 <k is less than or equal to zero and where r the distance along the straight line from the first reference point, wherein the prism structure comprises a plurality of prisms having a prescribed peak angle, α, a height, h, a length, l , and a pitch, p, and the plurality of prisms include at least a pseudorandom peak angle, α, height, h, length, l , or pitch, p.