Hitachi Maxell Ltd. said Wednesday it has developed an ultrathin DVD, just one-13th the thickness of a conventional DVD, that can be stacked to create a compact storage device capable of accommodating nearly one terabyte of data. The new DVD is only 92 micrometers in thickness, compared with 1.2 millimeters for conventional DVDs, and has a data storage capacity of 4.7 gigabytes, the same as an ordinary DVD. When the disc is mounted on a special 100-layer cartridge, the cartridge boasts a data storage capacity of 940 GB.