Patent ID: 7789652

Claim:
Roller extruder for manufacturing Fresnel lens angular lens segments, each lens segment having a segment inner edge and a segment outer edge, the roller extruder comprising: a) blank roller; b) die roller having a first roller inner edge and a first roller outer edge, the die roller having two peripheral lens dies, the two peripheral lens dies comprising a first lens die and a second lens die, the first lens die and the second lens die being proximally joined proximal to the first roller inner edge and the first lens die and the second lens die having a primary angular displacement of approximately three hundred sixty degrees proximal to the first roller outer edge, and the die roller having peripheral Fresnel facet dies, the peripheral lens dies providing, as the blank roller and the die roller rotate through one complete revolution, for the extrusion of a first lens segment and a second lens segment, and the Fresnel facet dies providing, as the blank roller and the die roller rotate through one complete revolution, for the impression of curved Fresnel facet grooves in the first lens segment and the second lens segment, the Fresnel facet grooves of each lens segment having a center of curvature which is proximal to the segment inner edge; c) roller support structure; and d) roller drive mechanism.