Read-Out Signal Simulation of an Optical Disk Having an Oxide Super-Resolution Film

The read-out signal simulation of an optical disk having a cobalt-oxide super-resolution film was performed to find the optimum condition for a higher recording density of the super-resolution disk. A simple model of the complex refractive index change in a super-resolution film due to its temperature was applied, which can explain experimental data. It was found that this type of super-resolution disk must increase its reflectivity as the incident laser-beam intensity rises. To confirm this experimentally, a new super-resolution disk with an added Ge–N layer was prepared, and its read-out signals were measured, which agreed well with the calculated results.