US Patent 7704418 Manufacturing optical elements

An optical element is manufactured using a replication tool comprising a negative structural feature defined in a replication side of the replication tool, and a peripheral feature formed in the replication side of the replication tool adjacent the negative structural feature. The negative structural feature defines the shape of the optical element. A replication material is disposed between a substrate and the replication tool, which are moved toward each other. The peripheral feature confines the replication material to a predetermined area of the substrate. The replication material can be hardened to form the optical element from the replication material attached to the substrate.