Readout signal analysis of optical disk based on an approximated vector diffraction theory

This paper proposes an approximation method of readout signal simulation for read-only optical disks based on a vector diffraction model. The boundary condition at the recorded surface is assumed to be described by a complex tensor reflectivity, which corresponds to the complex scalar reflectivity in the case of scalar diffraction model. The formulation of the readout signal is similar to the scalar model. Because the diffracted field is given by the Fourier transform, the calculation is straightforward and the calculation time is only about 80 times larger than that required in the scalar model calculation. This model is expected to provide a convenient method to study the basic readout characteristics of large NA optical disk systems.