Blu-ray Discs to Last 100 Years?

First there were CD-ROM discs, then DVD discs. Now a new technology hit the stores this year: Blu-ray discs. These discs are the same size as CD and DVD discs but store more data. A lot more. The Blu-ray discs for sale in computer stores now will store about 25 gigabytes of data. Several manufacturers claim they will soon be shipping Blu-ray disc drives capable of storing 100 gigabytes. That's approximately the same storage capacity as 167 CD-ROM discs or 71,428 floppy disks.

The Blu-ray Disc Association that developed this new format is a group of the world's leading consumer electronics, personal computer, and media manufacturers. Its membership includes Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson. It already has the support of leading computer and gaming manufacturers, as well as seven of the eight major movie studios, so its succession to the storage media crown is fairly guaranteed.

You may ask, "How can a disc hold so much data?" Basically, the new format carries CD/DVD formats to the next level. Both DVD discs and the new Blu-ray, or "BD", discs employ optical technology, which uses a laser to read and write the data. While DVDs use a red laser, BDs use a blue-violet laser - hence the name. The blue violet laser's shorter wavelength focuses the laser spot with much more precision than a red laser. This packs the data more tightly, fitting much more data on discs that are no bigger than their CD/DVD predecessors. These disks look like CD-ROM disks but are different internally. The Blu-ray disks also cost significantly more money today than do CD-ROM or DVD-ROM disks, but the price should drop once the Blu-ray discs move to mass production.

What's more, CD-ROM and DVD discs are believed to reliably store data for only a few years. Panasonic says that its new 4-layer, 100-gigabyte Blu-ray discs are so durable that you'll be able to retrieve the data in 100 years' time. Of course, this assumes that someone will still own a Blu-ray drive 100 years from now.

Genealogists, historians, archivists, and others often worry about the life expectancy of storage media. Panasonic claims its new discs will last longer than today's acid-based paper.

Panasonic's 100-gigabyte Blu-Ray disc uses Te-O-Pd, a tellurium suboxide, palladium-doped, phase-change recording film. The film is said to have a high transmittance and crystallization rate, which allows the disc to last a long time without losing data quality. I am not sure what all those words mean, but they sure sound impressive!

Panasonic has tested the new discs by using "artificial aging acceleration tests." This testing process tests the effects of humidity and temperature on discs over time. I wonder what will happen when people start handling, storing, and possibly scratching the discs. Even though their hard-coating protection is supposed to be much better than today's DVDs, the claimed "100-year durability" of the discs may seem a bit far-fetched.

I'll believe it when I see it, 100 years from now.

Comments

[Karen]

The significant sentences:

1. "Of course, this assumes that someone will still own a Blu-ray drive 100 years from now." [Not likely, since it is in the manufacturers' financial interest to keep coming out with new products/formats for us to buy.]

2. "Genealogists, historians, archivists, and others often worry about the life expectancy of storage media." [Maybe, but it's a far less significant worry than, say, obsolete, unsupported and/or proprietary file formats.]

3. "Panasonic claims its new discs will last longer than today's acid-based paper." [But most of today's paper is acid-free. Check the label next time you buy computer paper!]

4. "I'll believe it when I see it, 100 years from now." [As usual, wise words from Dick.]

[Robert Shaw]

Karen quotes and comments:
' "... worry about the life expectancy of storage media."
[Maybe, but it's a far less significant worry than, say, obsolete, unsupported and/or proprietary file formats.] '

but I disagree - availability of the bits is the biggest problem. The most important information is in language, and that can be stored in a plain text file with near-complete assurance that it will be interpretable in 100 years. Images are more questionable, but saving redundantly in several widely known formats (say jpeg, tiff, png) should be adequate. But just getting the digital data to the various possible unknown readers of the future, _that_ is difficult. Just throwing a disc into the box with the old photos isn't likely to be successful.

[Sally Jacobs]

I share your skepticism, Dick.

The first CDRs were predicted to last hundreds of years, and plenty of them failed before their 5th anniversary.

It's perfectly reasonable for consumers to want a CD that holds more information per disc. But what irks me is that so few people know that higher data density = higher probability for failure and/or data corruption over time.

Below is a download link for the PDF version of an excellent article by Tim Vitale called "Digital Imaging in Conservation: File Storage." This article was printed in the Jan '06 newsletter of The American Institute for Conservation of Historic and Artistic Works (AIC).

http://tinyurl.com/ygdldx

- Sally J.

[Margaret]

Sally said,

It's perfectly reasonable for consumers to want a CD that holds more information per disc. But what irks me is that so few people know that higher data density = higher probability for failure and/or data corruption over time.

This is what concerns me about using the DVD format for saving my voluminous family files. One scratch or surface failure could mean the inability to open or retrieve all the material on the DVD (or Blu-Ray, eventually).

The convenience of giving a repository your data on digital modes (to facilitate sharing with it's users) is made void if the repository doesn't periodically back it up to more secure and modern methods in the future.

[Robert Juch]

Higher density does NOT mean there's a higher probability failure or data corruption. I've been using computers for over 40 years and every year the density has increased while the failure rate has decreased. If you've been using PCs for any amount of time, I'm sure you remember when your floppy disks had unrecoverable read errors and when your hard disks lost files due to errors as well. What was the last time you have had an error?