Mold for diffractive aspheric lenses and method for making the mold

摘要

A mold ( 1 ) for diffractive aspheric lenses includes a substrate portion ( 10 ), and a pattern layer portion ( 12 ) formed integrally with the substrate. The pattern layer portion has a plurality of diffraction strias ( 120 ). A method for making the mold includes: 1) providing a substrate having an aspheric surface; 2) coating a photoresist layer on the aspheric surface; 3) lithographing a pattern on the photoresist layer, thereby creating two kinds of portions in the photoresist layer; 4) exposing one of the two kinds of portions of the photoresist layer; 5) developing the mold to dissolve unexposed portions of the photoresist layer; 6) etching the substrate between remaining portions of the photoresist layer; 7) removing the remaining portions of the photoresist layer and cleaning the substrate, thereby providing the mold.