We examine scattering of a family of initially parallel diagonally incident rays by a dielectric circular cylinder and show that the interior and exterior caustics that occur are qualitatively identical to those produced at normal incidence. We find, however, that (1) varying the plane-wave tilt angle has the same effect on the caustics as varying the refractive index of the cylinder at normal incidence and (2) high-order interior caustics are visible because of larger internal-reflection Fresnel coefficients at diagonal incidence than at normal incidence. We also observe noncaustic ray trajectories produced by the sharp peaking of internal-reflection Fresnel coefficients at large ray impact parameters, as well as another class of internal caustics produced by scattering from inhomogeneities in our glass cylinder.
© 1997 Optical Society of America
[Optical Society of America ]
C. L. Adler, James A. Lock, Bradley R. Stone, and Claudio J. Garcia, "High-order interior caustics produced in scattering of a diagonally incident plane wave by a circular cylinder," J. Opt. Soc. Am. A 14, 1305-1315 (1997)