Holographic Storage Overview at CNET

encebollado writes: "CNET has an article about how holography is being used to create next generation storage devices. The researchers promise they'll beat out DVD by an order of magnitude." Actually, it's an overview with four separate articles -- no bets on when the technology covered will really be available though.

Comments

You do have a hard limit.

[Christopher Thomas]

Also, there are no fixed limits on how much information you can store on hologram - you can always store something more, which will lower the quality of the rest of stored information, but you won't hit any fixed maximum number of bits, like with standard types of memory. Saying that it "[beats] out DVD by an order of magnitude" is totally ignoring the most fundamental features of holographic memory.

The problem is, if I don't care about the quality of the data retrieved, I could use /dev/null to store data and /dev/random to retrieve it and claim as much space as I want.

If you need to get your data back intact - i.e. with enough fidelity for you to rebuild the original data without loss - there turns out to be a hard limit to how much you can store with a holographic storage medium. The exact limit varies based on the geometry of the setup and of the holographic medium, but can be calculated. You can also measure it directly for any real system, which is presumably what the company involved did when citing storage densities for its prototype.

So, while the accessing method is very different, the storage limit for holograms scales in the same way as storage limits for other types of device (in this case, with the volume of the holographic film IIRC).