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Microholography Could Lead to 500 GB Discs
angrykeyboarder writes "Scientists have discovered a way to fit 500 GB of data onto DVD-sized discs. These discs would be created with a process called 'microholography, which combines multilayer storage of data with holographic imagery. From the article: 'Microholography allows data to be stored in three dimensions. The technology works by replacing the two-dimensional pit-land structures currently found on CDs and DVDs with microgratings, which are holographically induced using two laser beams. In other words, instead of recording to a series of bumps and pits like standard CDs, the new technology creates three-dimensional holographic grids that can be used for reading and writing data throughout the physical structure of the disc.'"
I blows me away how Sony missed out on the opportunity to use the MD format for data storage. It could have been the perfect 3 1/2 floppy drive replacement. How aggravating that they wasted the chance!
Life is not for the lazy.
A company called Constellation 3D developed "Fluorescent Multilayer" disks about 6 or 7 years ago. They even had a working prototype if I recall correctly. Followed the story for a while and then the company went bankrupt due to an investor pulling out (mugs!) Even back then they said they would produce first gen products of 120GB. There's even a WIKI history...... http://en.wikipedia.org/wiki/Constellation_3D Surely we should have moved away from a spinning disk by now!
Interesting....NOT
a qoute from wiki is that it will improve piracy protecion
"HD-DMD enables dramatic improvements in piracy protection, by taking advantage of the multiple layers of information."
They still never learn, what was made by man shall be cracked by man.
Holographic Memories; Scientific American, November 1995, by Psaltis & Mok
It does make some sense to spin a disk rather than reorient the beam. But a solid crystal holographic storage device not only has lots of locations within itself to store collections of data, but can also be turned on a turntable and have the beam attack it from different directions, storing more data in the same place but at a different angle.
3D holographic storage design has another benefit -- it is self-searching via "reverse" holography. You shine a laser off a target and let it reflect to the memory, and out comes as many copies of the reference beam as their are stored data sets (with a realistic situation of most dissimilar results being buried in noise). Each beam is proportional to the strength of the reference beam according to the similarity of the dataset it came from. You can pick the strongest if you want to find the closest match, or you can statistically test the range of beam strengths to check for uniqueness of the target, or any number of things. The search process is virtually instantaneous, the speed of getting the result limited only by the speed of the measuring and calculating processes.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
The MD failed for the same reason the Iomega Zip and similar devices did: companies want to profit in every possible way from their inventions to the point that their patents prevent others from doing anything useful with the technology. This reduces the market until the technology dies and nobody can revive it due to those patents.
I have no data handy about it, but I'm pretty sure the same practice was not applied to hard disks and floppies, otherwise we'd be still saving data to punchcards.
On the other hand, at the rate available bandwidth is increasing, there is a much smaller need for portability. With a 4G mobile data network you may as well leave most of your data in a RAID array (where 'D' stands for whatever the densest cheap storage mechanism is) and stream what you need, with a few GBs of local cache. Latency is still going to be a problem, but WAN latency is still lower than optical disk latency in a lot of cases.
I am TheRaven on Soylent News
I don't know if I need a single DVD-sized disc to store 500GB of data. What I think would be cooler is if that space was made redundant and strewn all over the disc, so I could store maybe 100GB or so (still way lots) and have the peace of mind of knowing that an accidental scratch isn't likely to lose me anything.
I personally don't own a desktop anymore and just hook my laptop up to a keyboard, monitor, and mouse when at home or work. I foresee the desktop dying except for hardcore gamers and servers. If I'm correct then spinning media doesn't make sense. Motors drain battery life and increase latency while throwing in a mechanical cog that can fail. -Portable CD players can last 30 hours on just two batteries. The motors aren't a big deal.
-My Discman 2 from 10 years ago is still spinning and reading discs prefectly despite numerous drops on pavement.
-As usual, minor latency isn't a big deal when we're talking about data backup. If this takes the place of the DVD, then it will not become your next harddrive that you install anything on. It would just take the place of the DVD and be a backup solution. When was the last time you got frustrated at a DVD's access times? Or when was the last time a DVD drive failed on you? Neither of these has happened for me. So I welcome any major improvement to the DVD-- I want to get rid of that 100-disc spindle full of data DVD's, and everyone keeps claiming to have a solution but nobody has actually brought one to market.
Seen the Dvdisaster project? It uses some of the space (15 percent by default) as parity data at the image level to make a disc a lot more secure from scratching or other forms of what would otherwise cause data loss. Hell set it to 50 percent and you can pretty much guarantee the disc will be recoverable however badly you scratch it.
Something you might find interesting anyway.
It's easier to fight for one's principles than to live up to them.
Nothing. The data does not have to be sequential. You could simply ignore the section that is damaged and retrieve the undamaged portion. What if they weren't disks? Maybe cubes or boxes? That would give you much more volume vs surface area, also if something happened to one side, you could always read it from another angle. Also, if you don't use the layers a few millimeters from the surface you could protect all you data from damage