Where can I find info on the ISO CD format?

An Ultra Density Optical disc or UDO is a 5.25" ISO cartridge optical disc encased in a dust-proof caddy which can store up to 30 GB of data. Utilising a design based on a Magneto-optical disc, but utilising Phase Change technology combined with a blue violet laser, a UDO disc can store substantially more data than a magneto-optical disc or MO, because of the shorter wavelength (405 nm) of the blue-violet laser employed. MOs use a 650-nm-wavelength red laser. Because its beam width is shorter when burning to a disc than a red-laser for MO, a blue-violet laser allows more information to be stored digitally in the same amount of space.