The Hyper CD-ROM is a claimed optical data storage device similar to the CD-ROM with a multilayer 3D structure, invented by Romanian scientist Eugen Pavel.
The bit of data being held as a change in fluorescence characteristics once irradiated with one or two lasers.
The Hyper CD-ROM technology is patented in 21 countries: the US, Canada, Japan, Israel and 17 European states.
[2] Despite its bold claims the technology has not been shown as a working prototype in the over twenty years since its announcement and there has been no commercial production.
In an interview about his work on the Hyper CD-ROM, Pavel stated that "the research for this project is 100% personal, [and] so is the support for experiments.