The M-Disk recent publication Millenniata is an optical disc designed to last for a thousand years (hence the name). Hitachi makes the units, using a 5 times more powerful laser of a conventional DVD recorder. The discs hold the same amount of data as a conventional DVD are designed to be read - not eliminated - by a conventional DVD drive.
How do they do?
-trade products, pre-recorded DVDs and CDs are based on a series of pits (holes) and land (no-holes) molded polycarbonate transparent lower layer of the disc. For the most is a thin reflective metallic layer. A laser shines through the bottom of the disk and the difference in reflectivity between the pits are read as data from the converter.
DVDs and CDs are both a kind optical disks, as data is read optically by a laser light.
The wells are in the top of the polycarbonate layer, which is itself surmounted by a shiny metal layer, to reflect the laser. There is a layer of lacquer to protect the polished layer, and then (sometimes) operates on top.
Recordable discs have virtually the same construction, but instead of wells molded into the polycarbonate layer, there is a layer containing a photosensitive dye, with the thin reflective layer of metal on top. The laser writes to the disk by changing the color of the dye. The drive reads the difference in reflectivity of the dye, instead of pits.
The new M-Disc uses a laser to etch pits in the recordable layer, rather than changing the color of a dye. So the laser reads the difference in reflectivity of the media in the data tier. Perhaps (as the disc is compatible with standard DVD-players) there is a reflective layer for more - or the data layer itself is reflective. As well as machine-readable media, is working much like a music CD manufactured, with the physical pits providing the difference in reflectivity when a laser shines on it.
The manufacturer claims that these discs will be readable for a thousand years, based on the forecast that the polycarbonate layer (the layer of polycarbonate shared by all CD) should last a thousand years, but that the data layer , which they say is "rock-like" (but of secret composition) is permanent until it is protected by the polycarbonate layer. Hey, is not a kind of metal "rock-like".
But no matter - that go a step further, testing their means against other recordable media and by far in the lead out. Worthy of note is the lack of evidence against manufactured CDs.
How long regular optical discs last?
Depending on the dye used, the duration of a CD or a recordable DVD is generally quoted to be 10 to 100 years.
Kodak testing says that "with 95% confidence, 95% of the population of KODAK writeable CD media will have a duration of data exceeding 217 years when stored in the dark at 25 ° C, 40% of RH after being recorded in a KODAK PCD Writer 0. "
, but said changes duration based on its exposure to heat, UV rays, humidity and possibly other environmental considerations. As a result, even if the media could be expected to take a decade (or 217) years, a part of the writable without CD after 3-5 years. Most manufacturers claim a duration of 5-10 years.
How long is a pre-recorded CD last?
The Council on Library and Information Resources (CLIR.org), an interested party in reliable data storage, says that expectations vary from 20 to 100 years for these discs. They also say that there is a consensus among the producers of CDs and DVDs ,, writable CD-R, DVD-R and DVD + R should have a life expectancy of 100 to 0 years or more, on the recommended storage conditions and rewritable (CD RW, DVD-RW, DVD + RW and DVD-RAM) the discs should have a life expectancy of 25 years or more.
M-Disc supports a life of 1,000 years.
Now, since the last data for a thousand years (like the books kept in the best conditions) is great. But what about the ability to read discs in a thousand years?
CD-ROM drives began to be popular around 1983. Although they were a bit 'expensive, which could hold about 700 MB of data. About five years later, the units were released on the market that could write to recordable CDs, and these units became popular later in 190. DVD has hit the single market around 1996 and could hold about 4.6 GB data - more than six times as much data in the same space of a CD. In 1997, the DVD-R was released, allowing users to record their own DVDs. One that I purchased in about 00 cost me about $ 00. At the time of writing this article (later 2011), this drive is listed for about $ 40. A dual layer DVD that can hold twice as much as a standard DVD it was made available in stores starting in 05 and a new dual-layer DVD burner you can have today for about $ 50 Blu-Ray was released commercially in 06, and a disc can hold 50 GB of data and a Blu burner -ray can be bought today for $ 0 or so.
The moral of this part of the story is that the formats change.
We are looking for more and more, faster and faster storage in ever-smaller, less expensive forms of media. CDs were a dominant form of optical storage media for about 15 years - more or less the practical life of the media. DVD has become the dominant form of life optical media, but the improvements is not compatible happened within ten years. The DVD is trying to have a run of 15 or 20 years - close enough to the expected duration of a disc. We had Blu-Ray and DVD dual layer only for a few years and I would say a phase-out of another ten years.
I am at the moment trying to download a cabinet full of removable drives. There are various optical, magneto-optical, tape and other units to removable magnetic media, such as Zip disks, Syquests and others. For more than a decade, I was offered a data transfer from an older format to something currently readable. Over the last five years, that part of my work has fallen away. I tried to sell these units on eBay, and other suppliers, and there is no market for them. Only a specialized market exists and sellers of these devices can not download them either. I can not give it away! Many of these are new formats of CDs and some are more recent DVD. At one time, some of these formats were quasi-standard and were ubiquitous as backup devices.
This Millenniata has created a form of media writable that they claim will last one thousand years is commendable. Their average seems to definitely be more resistant than other optical media. But what drives the technology is (as I said before) is more and more storage, faster and faster in a smaller, less expensive forms of media. Millenniata is coming out of the gate with the slowest average, more expensive with (presumably) the most expensive units. if the technology history is any guide, these drives and media will not become a standard and will have a much shorter period of 15 years. In something like ten years, these means can be just as easily visible and legible as 8 mm film today. A hundred years from now, no one will know what they are, let alone a thousand.
With their great YouTube videos, and a logo that I love, I believe that these will make a small, short but exciting splashes. It 's great that can hold up to being banged on a table or immersed in liquid nitrogen, but how many of us actually have this problem? The ExtremeTech site is certainly very excited about their "M-Disc is a DVD made of stone that lasts 1000 years", but in the end, draws a conclusion very similar to mine.
The M-Disc is a neat idea, but ultimately not much more useful than the media and technology already on the market for less faster, more capable. If this is their only product, the discs can be found intact hundreds of years from now, but I'm not so sure that the company will be.
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