<title>Spreading Of Light Beams In Ocean Water</title>

Abstract

Laboratory measurements of the irradiance distribution due to a laser beam and the radiance distribution due to a point source in a hydrosol have been made and the results analyzed. The analysis indicated that after proper accounting for absorption, the distri-butions may be scaled as a function of the scattering length rather than the more commonly used parameter, the attenuation length. The two distributions have also been shown to be equivalent as required by the optical reciprocity theorem. The measurements have given new insight into understanding the spreading of light underwater.