DIFFRACTION GRATING STRUCTURE AND METHOD FOR MANUFACTURING SAME

摘要

A diffraction grating structure comprises a substrate having a first surface and a second surface opposite to the first surface. A first grating is defined on the first surface and a second grating is defined on the second surface. The first grating includes a plurality of first grooves and has a first grating period. The second grating includes a plurality of second grooves and has a second grating period. The first groove and the second groove are formed by a fast tool servo system.