Optical element housing or mounting connector

An optical assembly comprising at least two optical elements, arranged in housings or mountings, at least one part of one of said housings or mountings being magnetic, at least a second part of another one of said mountings comprising an electro-permanent magnet, said magnetic part and said electro-permanent magnet magnetically fixing said one and other of said housings or mountings relative to each other.

An optical assembly comprising at least two mountings or housings with attached optical elements, at least one spacer element arranged between two of said mountings or housings, an electro-permanent magnetic coupling being arranged between at least two of said mountings or housings and said spacer element, providing a force joint.

An optical assembly comprising a first mounting part and a second mounting part and an optical element, one of said mounting parts being fixedly attached to said optical element, one of said mounting parts being fitted with at least one electro-permanent magnet, one of said mounting parts being a flexure part, the position of said optical element being adjustable by variable flexure of said flexure part, which is varied by a variable activating current of said electro permanent magnet.

A method of connecting mountings or housings of optical elements in lens systems of microlithography projection exposure machines by providing electro-permanent magnets, adjusting relative position of mountings or housings and subsequently activating said electro-permanent magnets by an electric current to magnetically hold the mountings or housings together in their adjusted positions.