BINARY OPTICAL ELEMENT AND PRODUCTION OF NONSPHERICAL COMPOSITE OPTICAL ELEMENT

摘要

PROBLEM TO BE SOLVED: To obtain a binary optical element usable in a UV region as well without depending on the refractive index of the base material by supplying metallic alcoholate to the surface of an optical element base material and pressing the same to form an oxide lay of a shape having ruggedness on this optical element base material. ;SOLUTION: A lens blank 7 made of quartz glass is arranged on a transfer mold 3 into which the product of hydrolysis of the Si alcoholate 6 is injected. The lens blank 7 is fixed by a clamp ring 5. Molding is executed while the relative positions of a mold 2 and the transfer mold 3 are kept monitored by a sensor 9 in such a manner that the desired positions are attained. The transfer mold 3 is formed by precision working a sintered hard alloy essentially consisting of WC to a diffraction pattern shape of a desired saw tooth shape in section. A diamond-like carbon film is formed at a prescribed thickness on its transfer surface. The transfer mold 3 and the lens blank 7 are released, by which the SiO₂ layer having the diffraction pattern shape of the saw tooth shape in section is formed on the lens blank 7.;COPYRIGHT: (C)1998,JPO