Optical Surfaces Ltd. reports on the development of a new polishing technique that has been shown to reproducibly improve the spectral filtering capability (finesse) of Fabry Perot etalons.

For over two decades – Optical Surfaces has supplied precisely matched Fabry-Perot etalon pairs to Table Stable Ltd. (Mettmenstetten, Switzerland) for use as a key component in their ultra-high-resolution JRS Series interferometers.

Operating in a uniquely stable manufacturing environment, Optical Surfaces is able to produce the required 50-mm diameter fused silica Fabry Perot Etalons pairs with matching accuracies of better than lambda/200.

Fabry Perot Etalons for ultra-high resolution interferometry

Dr Aris Kouris, Sales Director of Optical Surfaces said “Many parameters including material quality, optical figure, plate parallelism and coating quality are all critical to the overall performance of a Fabry Perot etalon. To maintain the competitive edge of the Table Stable Interferometer we are continuously investigating ways of further improving the quality of the matched Etalon pairs we supply to them. Our latest development project focused on how to improve the spectral filtering capability of the Fabry Perot etalon pairs by reducing surface ripples and microroughness. Our initial investigation using chemical polishing techniques brought some improvement, but degraded the matching accuracy of the etalon pairs. As a consequence, we refocused our efforts into developing new polishing techniques using conventional compounds. The results have been excellent – the new polishing technique has allowed us to almost eliminate surface ripples thereby improving the finesse of the Fabry Perot Etalons whilst maintaining all the other high-performance characteristics”.

For further information on ultra-high precision etalons for use in applications in interferometry, lasers and high-resolution spectroscopy please visit https://optisurf.com/etalons/ or contact Optical Surfaces Ltd. on +44-208-668-6126 / sales@optisurf.com.