The supplier of ultra-high precision Etalon plates for use in Fabry-Perot interferometers is Optical Surfaces, which provide the etalons as standard in materials including UV grade Silica and Germanium. Etalons are available in two basic forms, air-spaced or solid.
Designed for use at customer-defined wavelengths within the range 190nm to about 2µ, Optical Surfaces etalons are supplied with wedge angles of 5min of arc for smaller diameters, rising in steps to a wedge angle of 40min of arc for diameters greater than 70mm. Dr Aris Kouris of Optical Surfaces commented: "Drawing upon our unique stabilised manufacturing environment and team of skilled optical craftsmen we regularly supply etalons in a range of shapes and sizes with matching accuracies to lambda/300".
Dr Kouris added; "Optical Surfaces has built up a worldwide reputation for producing these super-flat components, supplying many customers in scientific institutes, observatories and industry. For example the set of 165mm diameter Fabry-Perot Etalons that we supplied to the Massachusetts Institute of Technology (MIT), are a key component lying at the heart of the Millstone Hill Atmospheric science facility operated in cooperation with the University of Pittsburgh (USA). The purpose of this instrument is to measure Doppler shifts in the atmosphere.”