Haifeng Wang Data Storage Institute (Singapore) Gaoqiang Yuan National Univ. of Singapore (Singapore) Weilian Tan Data Storage Institute (Singapore) Luping Shi,Chong Tow Chong National Univ. of Singapore (Singapore)
Different definitions of spot size and depth of focus in optical data storage systems are analyzed and compared numerically. It appears that the differences between the definitions become more significant as the numerical aperture of the optical system increases. The relationship between spherical aberration and axial intensity is studied, and a general definition of the depth of focus based on this analysis is proposed.