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Turner Testing Holographic Storage
Izmunuti writes "An article in ComputerWorld describes tests by Turner Entertainment of a holographic storage system from InPhase Technologies as a possible replacement for magnetic tape for storing their movies and other programs for playback and broadcast. The article states that each holographic disk holds 300 GBytes." Even more impressive is the cost per terabyte estimated for just a few years down the road.
but this and this is. Why did the summary only link to the press release and not the info? I had to browse the site a little get some interesting stuff.
And for my fellow PDF viewing overlords, read this this and this.
This might not be a typo, if they are talking about writing speed. Most holographic storage technologies depend on chemical reactions for recording. These reactions are a very serious limiting factor to writing speed.
On the other hand, reading speed can be tremendous. You get a full page of data for each reading operation. Some people will say you can read "at the speed of light", because all it takes to extract a page of data is to let diffract a laser beam through the holographic media. This is not completely true, as you still have to convert the data from its original optical form to an electronic form suitable for computer. This is usually done using arrays of CCD or CMOS detectors, and their speed is the limiting factor when reading data.
If I can get a hand on several documents that I know to be hiding somewhere on my computer, I will post actual speed figures which might give you a better idea of the typical transfer rates.
A bit of followup : this might not be the bleeding-edge figures, as I suppose there have been further advances in the meantime.
I know that a CMOS detector integration speed of 1ms has been reached several years ago on holographic RAM (I am not talking here about holographic disks). As the integration speed is the limiting factor during the readout, that means you roughly read 1000 pages of data per second.
Usually, these pages of data are arrays of 1024x1024 values, coded on 256 different brighness levels (therefore equivalent to 8 bits, or one byte). That means you can get a reading speed of 1GB/s on that technology.
However, I think most of the research nowadays is turned towards holographic disks, because they are more suited to the "write once slowly, read many times quickly" behaviour of holographic memory. The main problem here is to find (or create) an holographic material suitable for this usage. So far, data density has been much lower in holographic disks than in holographic RAM because of this issue.
People once said the same thing about blue laser hd-dvd's. And, before that, they were saying it about DVD too.
-Eric
SJW: Someone who has run out of real oppression, and has to fake it.