When last we discussed holographic storage it was over the decline of the industry as a whole and what could be done about it.
Perhaps I posted too soon. GE research just announced that they have come out with a new media formulation offering the possibility of 500GB per single disk platter and broadens the holographic storage ecosystem.
GE also mentioned that there was no need for the holographic storage to be in the form of a disk. InPhase Technologies also had talked of other form factors besides rotating media.
Do rectangular form factors make sense?
Some of these non-disk form factors remind me of the storage cards in StarTrek or memory cards for old programmable electronic calculators. But can they gain any traction?
The only reason a disk makes sense is that with rotating media the heads need only travel in one direction (in an arc with today’s magnetic disks, in an line with today’s CDs and DVD devices) to access a track of data. The rotation of the platter would move all the rest of the data on a track underneath read-write heads.
With a card or any other rectangular form factor, heads and/or media would also need to travel in at least two directions to access data. Of course magnetic tape is a rectangular form factor, and today tape heads move in a single dimension (across the tape width) while the media flows under the heads in an complementary direction, linearly.
So would some form of holographic optical tape make sense. Probably, but the multiple layers needed for holographic storage will require some amount of depth to make it dense enough. Tape’s current volumetric density may be hard to exceed substantially with this multi-layer optical media.
On the other hand, cards could be inserted into a card reader to supply one of these two directions for data access. But this may be hard to do manually at the fine grained track and/or data cell dimensions of today’s data density. Hardware to automatically move the cards down a track of data can certainly be done it just takes technology.
All that seems to show that disks probably make more sense. The fact that with GE’s new media, holographic disk drives could read/write todays CDs, DVDs, and BlueRay disks would make it much easier to gain market traction.
With GE’s entry into holographic storage they are also possibly looking to use the technology for medical imaging. At the densities being discussed, lots of x-rays, CAT scans, MRI scans, etc. could easily fit on a single piece of holographic media.
As an industry we have been talking about Holographic storage since the early 90’s. The promise of this technology has always been significant more data per square inch than currently available technologies. But it has been a difficult technology to get to work properly. There’s just a lot of technology that has to be mastered to make it happen, e.g., media, heads, page digitizers, etc.
Nevertheless, holographic storage continues onward.