Abstract

Phenomenologies of light scattering from liquid drops in air are well known because of meteorological manifestations (e.g. rainbows and glory) and because of practical applications.¹ Effects of diffraction, interference, and focusing in scattering from bubbles in dielectrics (e.g. air bubbles in water, ice, and glass) have been only recently explored.^2-7 A bubble, or bubble-like object, differs from a drop-like object in that the refractive index n_i of the scatterer is less than the index n_o of the surroundings. As in the case for spherical drops,¹ bubbles may have backward^2,6,7 and forward² glories enhanced by axial focusing (though the detailed descriptions differ from those for drops). There is an angular region of scattering unique to bubbles in which diffraction, interference, and dispersion are significant. This is the region near the critical scattering angle.^2-5 In this paper we summarize the first observations of a novel effect of critical-angle scattering: the appearance of colored bands in the far-field scattering of white light.

© 1983 Optical Society of America