spritzgegossene photochemical lens and method for its manufacture

摘要

A lens has two or more layered sections of thermosetting material, and a substantially homogenous formation in which at least one of the layered sections has an active photochromic material present. The article is made by: forming a mould cavity from first and second mould halves; loading the mould cavity with a first thermosetting material; partially curing that material; changing the second mould half to define a subsequent mould cavity in which the partially cured material is present; loading the subsequent mould cavity with a subsequent thermosetting material; and curing the first and subsequent thermosetting materials. At least one of the thermosetting materials is loaded with an active photochromic material.