Huge capacity optical memory using DWDD-MO recording

We improve the linear density and the user data-transfer rate, simultaneously. To achieve this aim, we prepared a wide-land structured domain wall displacement detection (DWDD) optical storage disk with a low dropout rate instead of using the land/groove structured disk of the previous study. In addition, we employed 8-9 modulation for the data modulation code instead of (1,7)RLL if the dropout rate rate was low.