A feasibility study of writing compensation for tangential tilt

For achieving a higher density than that of current digital versatile discs (DVD), a high numerical aperture(NA) and blue wavelength light source is te sted to increase the areal density. In contrast to this positive effect, th e coma aberration is doubled with a NA of 0.65 and wavelength of 400 nm com pared to that of the current rewritable DVD at the same disc tilt. Addition ally, the effective power density for recording is much smaller than that i n the case of a DVD with a tilt. In this paper an efficient compensation me thod for disc tilt will be presented.