Method of measuring the phase function of a turbid medium in the small scattering angle range

A method is described for measuring the phase scattering function of a turbid medium in the near forward direction. The method is based on the use of a transmissometer with a variable field of view and is suitable for measurements on natural media, such as water or turbid atmospheres. Some precautions to be taken to avoid the effects of multiple scattering are indicated. Results of laboratory tests on suspensions of latex spheres in water are presented. An example of the use of the instrument in natural fog is also shown.