All analysis of the beam-wave scattering from arbitrarily shaped pits at a three-layered dielectric interface by the boundary-element method

摘要

Simple models of direct-read-after-write (DRAW) type optical disks using tellurium as a recording material are analyzed. Specifically, a BEM (boundary element method) analysis of the scattering of a light beam from arbitrarily shaped pits or bosses at the interface of a three-layered dielectric medium is presented. In addition, the characteristics of the sum and the differential signal output by all assumed split detector are discussed. Numerical results indicate that the V-shaped pregroove shows a better signal-output characteristic than the rectangular one for the E-polarized case.