Fluorescence microstructure using a laser/fiber optic profiler

Field tests were conducted during Aug/Sept 1989 of the second generation of a laser/fiber optic fluororneter attached to a microstructure proffling instrurnent (Rapid Sampling Vertical Profiler - RSVP). This instrumentation is designed to provide centirneter-scale biological measurements coincident with and at the same sampling frequency as those for temperature, conductivity, and horizontal velocity microstructure. The instrument used during the summer of 1989 employed a 200m dual fiber system, SMA optical fiber connectors used underwater, and an optrode (12mm diameter) containing two fibers, GRIN lenses, and filters. Shipboard laser excitation (488nrn or 514nm) was transmitted down a 2OOtm core excitation fiber, and the fluorescence emission spectrum returned via a 400pm core detection fiber to a shipboard multichannel array detector. Fluorescence emission spectra were acquired 30 times per second at an instrument drop rate of approximately 60 cm per second.