A new approach to measure the volume scattering function.
We present a novel optical approach to measure the volume scattering function (VSF) by image detection. The instrument design, based upon a combination of two reflectors, uses a unique measurement principle and allows the rapid simultaneous determination of scattering at a wide range of angles. The advantages of the newly developed scattering meter are that: 1) it can determine the scattering function from 8° to 172° at 1° intervals without changing the sensitivity of the detector, without moving any optical parts, and can do so within a few seconds, 2) the unique optical design facilitates determination of the spectral VSF over the full visible spectrum, i.e. it can obtain the VSF at a specific wavelength with an optional wavelength-resolution. Measurements under controlled conditions for the assessment of the instrument agreed well with theoretically predicted scattering functions. Measurements with cultured phytoplankton of different species revealed a significant variety of the VSF together with spectral variation. The observed results will stimulate and improve radiative transfer and/or two-flow models of light in the ocean, which is an important role for ocean color remote sensing algorithm development, particularly for coastal regions.
Institute for Coastal Research, Helmholtz-Zentrum Geesthacht, Center for Materials and Coastal Research, Max-Planck Strasse 1, D-21502 Geesthacht, Germany. Hiroyuki.Tan@hzg.de
Hiroyuki
H
Tan
Roland
R
Doerffer
Tomohiko
T
Oishi
Akihiko
A
Tanaka