A device for protecting moored spectroradiometers from biofouling

A shutter mechanism for reducing the effects of biofouling on bio-optical instruments deployed on oceanographic moorings has been designed, built, and tested. The initial development was carried out on a spectroradiometer. The optics of the spectroradiometer are protected by copper shutters that rotate out of the field of view prior to a measurement and rotate back after the measurement is completed. The shutter system can sense an obstruction and, if one is detected, attempt to rotate in the opposite direction. The controlling software stores the home position in the memory so the shutter can return to cover the optics, irrespective of direction of rotation. The system has been tested in the equatorial Pacific, where it has provided five months of data that are unaffected by biofouling.