Interferometer Modified for Orbit

An improved mount for a Fabry-Perot interferometer promises to reduce distortion in the etalon and eliminate finesse degradation from launch vibration. The mount, which will be incorporated into a satellite-based instrument to perform daylight measurements of atmospheric aerosols, was designed by Jack A. McKay of Remote Sensor Concepts LLC in Washington and David Rees of Hovemere Ltd. in Bromley, UK.

McKay and Rees clamped the etalon between cantilevered steel beam springs, with pivot pads at the contact points to isolate the plates from transverse and rotational forces.

A test etalon, described in the January issue of Optical Engineering, showed no damage and a defect finesse of 46 after vibration tests at 14.1 g.