Technology that slashes the time it takes to back up corporate data from 12 hours to 30 minutes could be available within two years.

Cambridge-based Polight Technologies has secured $5.4m worth of funding to develop Holodisc, a CD-sized unit that uses three-dimensional holographic data storage technologies. The discs can hold 500GB to 1TB of data and have read/write transfer speeds of over 1Gbps.

This compares with the current limit of 4.7GB for a DVD and a read/write maximum around 3MBps.

Michael Ledzion, chief executive at Polight, told vnunet.com: "Big corporations will eventually use this technology.

"It could, for instance, reduce a 12-hour back-up to half an hour, overcoming pressures on the daily archival window. Also, tape has a low archival life whereas holographic storage could last up to 50 years."

He said performance could be enhanced further by using holographic content-addressable memory techniques to achieve super-fast data searches.

Consumer products, such as streaming for high definition television feeds, photography and video archiving and retrieval, will become a reality with the technology.

Photo-polymers are light-sensitive materials whose state is changed by the action of a laser. By splitting the light beam and altering the focus, data can be written throughout the substance, achieving huge densities.

For non-moving lasers the data read speed is potentially close to the speed of light. But the difficulty has been finding a photo-polymer that is not unduly sensitive to temperature and humidity.

Polight believes that it has developed a higher specification polymer than US company InPhase Technologies, which is why it can achieve higher capacity. "We have demonstrated it internally," said Ledzion.

Polight's new funding has come from the Cambridge Gateway Fund and NIF Ventures in Japan, along with existing UK and US investors.

Other companies are working on similar products, and are also promising high-capacity products.

InPhase, which signed a deal with Hitachi earlier this year, is working on a 100GB disk and 20MBps transfer speeds. But its products could work out cheaper as it will use the low-cost red and blue lasers already developed for DVD.

A third company, Optware of Japan, whose venture capital funding includes $5m from Intel, is also aiming to reach a 1TB capacity and a similar transfer speed to the Holodisc.

But, whereas the first two use new photo-polymer materials, Optware claims to have developed a reliable way of storing in 3D format on existing CD and DVD media.

Sample shipments of a write-once disc are planned for next year, but the capacity and speed is undisclosed.