Fabry-perot etalon and assembly therefor

Abstract

The Fabry-Perot etalon includes first and second mirrors 72 spaced from one another by a spacer element 70. The spacer lement is provided with sides which provide support respectively for the mirrors. An optical cavity extends between the mirrors and is provided by a bore 18. A number of cut-out surfaces are located symmetrically about the optical axis of the cavity. The cut out surfaces 78 are concave. Support elements are positioned about the spacer and are configured to have a compressive force directed towards the centre of the cavity. Figure 9