A US firm says it has set a commercial data storage record by achieving 515 gigabits (Gb) per square inch.
Magnetic disks have a storage density of about 37.5Gb per square inch
InPhase Technologies says it reached the level using a holographic drive, which has a higher capacity than conventional magnetic storage media.
It said the technology could eventually lead to a holographic disc that could hold more than 100 DVD-quality movies.
InPhase expects to unveil its first holographic drive later this year, with products of up to 1.6 terabyte coming.
Holograms use a three-dimensional image generated by lasers to store information.
The concept has been around for several decades but the optical storage technology has only become feasible in the last few years.
Chief technology officer Kevin Curtis said previous tests carried out in April 2005 had only achieved 200Gb per square inch.
By comparison, magnetic disks, such as those used in the hard drives, can manage a storage density of about 37.5Gb per square inch.
"We are particularly pleased at the rate of improvement," he said. "The latest results from our ongoing tests on holographic data density have surpassed expectations."
InPhase says the benefits of holographic data storage will include allowing technology managers to archive data in less space.
The first generation of InPhase drives will have a capacity of 300Gb on a single disk.
"The technology represents a potential alternative to incumbent technologies for archival storage requirements," said Wolfgang Schlichting at analysts IDC.