Diver-operated instrument for in situ measurement of spectral fluorescence and reflectance of benthic marine organisms and substrates

A sell-contained diver-operated underwater instrument is developed to make in situ measurements of spectral fluorescence and reflectance of benthic marine organisms and substrates. The instrument, designated the benthic spectrofluorometer (BSF), is built around a single-board spectrometer with a 1024-element CCD array. Light input to the spectrometer is via a fiber optic cable, In fluorescence mode, the unit provides manual user-selectable excitation wavelength and measures fluorescence emission over the full visible spectrum. The BSF can also measure the spectrum of downwelling ambient light or of light reflected from surfaces of interest, enabling calculation of spectral reflectance. The instrument has been used successfully at several field locations, primarily for investigation of optical properties of coral reef organisms and in collecting baseline data in support of remote sensing systems. The instrument is described and representative data are presented. (C) 1997 Society or Photo-Optical Instrumentation Engineers.