A new instrument for optical forward scattering phase function surveys

Abstract

In order to predict the performance of in the water and through the surface laser communication systems, it is necessary to know the inherent optical properties of the water environment. In particular, knowledge of the absorption and scattering coefficients and the forward scattering phase function (FSPF) are required. Analytical models and photon Monte Carlo simulations can then make use of these inherent optical properties to predict system performance. In this paper the authors describe the design of a new device that can be used to conduct FSPF surveys. The device makes use of a green helium-neon laser operating at a 543.5 nanometer wavelength and thermoelectrically cooled CCD camera to make real time measurements. The system is powered from the deploying surface vessel and the data is recorded at each depth by a shipboard portable computer. In this manner vertical profiles of the FSPF can be obtained. The authors present some early results.