Angular Dependence of The Intensity Temporal Profiles of Scattered Pulses in Diffusive Regime

In this paper, the angular dependence of intensity temporal profiles for three sample media of different scatterer size are described. Detection angles around a fixed point are varied. Similar detection points in each media have been chosen along two directions: forward - along the light source launching direction, x-axis; and lateral or perpendicular direction, y-axis, for comparison. Measurements show the existence of a strong angular dependence of light traveling in a highly scattering media even for distances as large as 20 transport mean free path. More light is observed in the forward direction than in the lateral direction. The strong angular and spatial dependence indicates the existence of an anisotropic behavior of photons from the source directionality. To describe the high degree of anisotropy of photon migration in the medium, two new anisotropy parameters are introduced.