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InPhase Presents Holographic Rival to HD-DVD and Blu-ray

Ron Tarasoff: “This is an ideal way to store high-quality, high-definition movies”

InPhase Technologies could start producing a disk the size of a DVD, which can store up to 60 times more data than a normal DVD, as soon as next year.

The disks will be capable of storing up to 300GB each using the "Tapestry" a holographic memory technology which stores data using the interference of light fascicles. Due to its technology, devices that use this disk will be able to read and write data up to 10 times faster than a normal DVD.

InPhase Technologies is not a new player on the market - it was formed by the alliance of Hitachi and Maxell. A public demonstration of the new disk was held at the International Broadcast Equipment Exhibition in Tokyo last week.

"This was done to investigate the feasibility of using holographic storage for broadcasting television content," Ron Tarasoff, vice president of broadcast technology and engineering at Turner Entertainment Networks.

"This is an ideal way to store high-quality, high-definition movies because the extremely large capacity of holographic disks enables us to store TV programming as files, and the data rate allows us to migrate files on and off the disks quickly."

"Our role in the commercialization of holographic storage is critical to Maxell's overall strategy of technology leadership in recording media," said Tom Tanaguchi, VP and Executive Officer of R&D at Hitachi Maxell.

Today's DVDs read data by measuring the microscopic ridges on the surface of the disk. The same technology is used by the next-generation Blu-ray and HD-DVD formats, but they take advantage of shorter wavelengths of light.

Light from a single laser beam is split into two beams, the signal beam (which carries the data) and the reference beam. The hologram is formed where these two beams intersect in the recording medium.

The process for encoding data onto the signal beam is accomplished by a device called a spatial light modulator (SLM). The SLM translates the electronic data of 0's and 1's into an optical "checkerboard" pattern of light and dark pixels. The data is arranged in an array or page of around a million bits. The exact number of bits is determined by the pixel count of the SLM.

At the point of intersection of the reference beam and the data carrying signal beam, the hologram is recorded in the light sensitive storage medium. A chemical reaction occurs in the medium when the bright elements of the signal beam intersect the reference beam, causing the hologram stored. By varying the reference beam angle, wavelength, or media position many different holograms can be recorded in the same volume of material.

In order to read the data, the reference beam deflects off the hologram thus reconstructing the stored information. This hologram is then projected onto a detector that reads the data in parallel. This parallel read out of data provides holography with its fast transfer rates.