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A Terabyte of Data on a Regular DVD?
Roland Piquepaille writes "This is the promise of the 3-D Optical Data Storage system developed at the University of Central Florida (UCF). This technology allows to record and store at least 1,000 GB of data on multiple layers of a single disc. The system uses lasers to compact large amounts of information onto a DVD and the process involves shooting two different wavelengths of light onto the recording surface. By using several layers, this technique will increase the storage capacity of a standard DVD to more than a terabyte. Read more for additional references and a diagram showing how this two-photon 3D optical system reads data."
Glad I didn't buy blue-ray or HD-DVD, I knew they were both scams!
Soon someone will announce that by using blue laser they get blu-Terabit-DVD and another will announce blu+terabit-DVD and one more blu-terabit+DVD and finally a blu+terabit+DVD. By the this time users would have been fed up and gone on a nice fishing trip in the Owen's river in California.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Can't help wondering how durable the resulting storage solution will prove to be. Maybe it's just me, but I'm always wary of solutions that use things for purposes they weren't designed for.
something big enough to hold my pr0n collection!
By the definition of a DVD (yes, just like the various "color" Book standards that defined CDs, there are standards that define DVDs), this new technology will not result in a standard DVD by any means.
More proper terminology might be "in a standard form factor 12cm optical disc".
retrorocket.o not found, launch anyway?
Both articles repeat the phrase "uses lasers to compact large amounts of information onto a DVD" and then state that several layers would then be utilized. First of all, what the hell does using lasers to compact information mean? As far as I can tell, the articles explain how they are able to cause a state change in recording media with two wavelengths of light, and read it using a single wavelength, and that this media layer is particularly thin, allowing for multiple layers to be stacked up on the disc.
In my opinion, if you're going to the trouble of utilizing a multiple beam system in your drive, holographic storage makes a lot more sense, as both beams are the same wavelength (meaning only a single laser and a beam splitter are needed), your read times are going to be tremendously faster, due to the data all being stored in the same layer, obviating the need to refocus or switch beams, and finally, due to the nature of holography (in that small sections of a hologram contain the information needed to reconstruct the entire hologram), a disc with holographic storage should be much more resistant to read errors resulting from scratches, whereas with one of these, a scratch could render data on several layers unreadable.
I have enough trouble with my regular DVDs getting hosed. I imagine this would only make the process of data retreival even more delicate. Can the data be stored more robustly if some storage capacity is given up?
Oo! Oo! Could this be done with software, even if the manufacturer decides to go with one nonrobust terabyte?
Step into a huge movement. Don't Tread In Me.
If this is using essentially the same technology as DVD i think the read/write speeds would be awfully slow to handle 1 TB of data. If the bits are squeezed into a smaller surface area (instead of just layerd on top of eachother) if should read faster but if the space the bits take up is the same I think it would have simial I/O performance. After all, you can only spin a disc so fast (10-15K RPM).
Unless they find a way to read/write to multiple layers simultaneously and very efficiently, I think it would be really slow. At round normal DVD I/O speeds, burning one of those suckers would take like 60 hours!
Universities like to announce stuff like they are a big breakthroughs when in reality they have little to no impact. Get's their names in paper...
I hear and I forget. I see and I remember. I do and I understand. -Confucius
But is that really true? Is there significant degradation? VHS causes degradation during every play cycle not because you use the same device to read and write, but for two reasons: One, your VCR creates EM fields and VHS uses analog magnetic recording. So any time you put a tape in your VCR you're erasing it a little, whether you play it or not, just because there's a transformer in the same metal box as your tape. Two, the head in your VCR does helical scanning. Since the head therefore has to be round, so that 1) it can spin and 2) as it spins the distance from the axis of rotation to the tape has to remain constant, the tape also must describe a round path. The only way it can do this is if it rubs something so it might as well rub on the head. It pretty much has to anyway, because at the time it was outside our technical ability to use a much stronger signal - which probably wouldn't have been a good idea with analog recording anyway. The result is that the head physically wears away some of the coating as the tape passes the head. This is true of any system in which the recording medium contacts the read head, but it's especially true of VHS because you have a rapidly rotating head to deal with.
As an aside, this is why you should never pause VHS unless you're actually trying to see something paused, and then you should unpause it as rapidly as possible, because otherwise you're stopping the tape but not the head, and the head will sit in one place rubbing away the magnetic coating on the plastic tape. This is why you should never rent porn on VHS, all the good parts will be missing :D
Anyway, back to the topic at hand. I know this is not directly comparable for some obvious reasons, but I want to bring up Minidisc. While Minidisc is a MO drive and thus uses a substantially different technology, it might be worth discussing. MO works by using a laser to heat a very small region of the disk to the Curie Point, and then you write it with an electromagnet as it cools. Nothing happens below the curie point. Now, I know far less about CDR or DVDR than I do about this, unfortunately, but AFAIK it's based on the intensity of the laser, right? So here's my question, is there actually any significant degradation when you use the laser to read, or is the power level so much lower that there's really just not enough energy to cause it?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"