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Pioneer Ultraviolet Laser Promises 500GB Discs
No Fortune writes "Here's an article indicating that Pioneer is developing an ultraviolet laser for data storage. Since the wavelength of ultraviolet lasers is shorter than the wavelength of blue lasers, the beams are finer and they can pack more data into per square inch. This gives a data rate 20 times more than the blue laser Blue-ray disk."
People more versed in physics than I am can answer this:
:)
The lasers used for optical media keep on progressing to higher frequency light, which is better able to resolve things. Where is the likely end for optical media?
Past ultraviolet light is x-rays and gamma rays I think... Will they be used for optical media? They are known as "dangerous", but perhaps in low power situations they aren't too bad? Or, you could just have the optical drive shielded in lead
Microscopes haved moved past light, into "electron microscopes", which used streams of electrons to resolve things that light cannot. Will that be possible with our optical media techniques?
I see nothing about who developed the UV laser, all I see is that Pioneer is using them to write (and read) optical storage. The innovation is that they had to use a carbon mask to reduce scattering.
Of course, I can't read Japanese, so perhaps the original article is more informative and/or accurate.
Other companies already have UV diode lasers in production, like Nichia since 2002. However, I see nothing here indicating that Pioneer has developed the UV laser that they're using for this new disc format.
Anyone who reads Japanese care to track back and get more details?
Ce n'est pas un vrai mouvement de robot!
Just so I trust that my precious video of that birthday party is conserved...
I am willing to only get 100 GB per disc, if the redundant copies in the 500GB space give me a good chance of seeing the 100GB I want...
Super-redundant error-tolerant copy software anyone? I sure want it to tbe open-source, so that I can trust it will survive for a few years.
This issue is a bit more complicated than you think.
I'm sure that Pioneer has considered the fact that UV light gradually destroys most plastics.
So what type of material will these UV laser disks be made of?
All that we see or seem is but a dream within a dream.
It's been what? 20 years now that we've been using CDs and their cousins. I wonder when we'll make the jump to a new medium and what that medium will be.
And what happened to FDs? they were supposed to be the next big thing (tm).
The article only discusses write techniques. I'd like to hear if there are any peculiarities involved in reading it before I make guesses as to the delay before production. I'd also like to know if they only have a tube or if they have a diode already.
You need a laser with comparable or finer wavelength to the writing laser in order to read an optical disc.
This is almost certainly a frequency-doubled or even frequency-tripled laser, which means it's very power-inefficient (I believe there were old green laser pointers that were frequency-doubled IR; they got awfully warm, as most of the pump beam stayed as IR, and was wasted).
Source laser isn't mentioned in the short blurb (and the full blurb is subscribers-only), but I'd guess it's an excimer laser similar to the kind used for EUV photolithography, if it can make 70 nm holes. In fact, it wouldn't surprise me to learn that it's _exactly_ that type of laser, and that this experiment was done in a photolithography clean room. Excimer lasers are gas lasers that produce output in the near-UV. The 193 nm light used for photolithography a generation or so ago was from frequency-doubled argon fluoride excimer lasers.
We have UV LEDs, and so presumably low-power UV laser diodes are available in research labs, but getting something that can reliably make holes 70 nm wide would probably take frequency _tripling_ at this point. So I'd put money on a gas laser at the moment, with a tripled blue or violet diode or a doubled intermediate UV diode laser "some time really soon now, honest".
Producing light of the needed wavelength without frequency doubling would take a pretty exotic material with a bandgap that puts it well into the "insulator with extreme prejudice" range (lots of doping required).
Most plastics lose clarity and become brittle under UV exposure. Focusing a UV beam, even if only at a miniscule power, at such a small track width seems to introduce a whole slew of new problems. I've heard that Blu-ray will be the last generation of plastic-substrate optical disks unless better UV resistant materials can be developed.
There have been many comments about using gamma/X-rays in order to write to discs and getting even better storage and people saying it's not possible because it would go right through any disc.
Last year in nuclear physics lab we did an experiment where we had a gamma ray source and a detector and took various measurements of how far they could go through various compounds (aluminum, copper, and lead). Let me say that 30 cm of aluminum blocked less than 10 cm of copper which blocked less than a cm of lead. I bet if they made the discs with gold* instead of whatever they use now they might reflect enough of low-frequency gamma or x-rays to read the discs, despite them being really expensive.
*I think too many people microwave discs to let people use lead.
**Techically gamma rays are produced from nuclear transition and X-rays are produced from high energy electronic transitions. I am pretty sure they would not use radioactive materials to obtain gamma rays and that they would use electricty to obtain X-rays but since this convention has been ignored so far, I didn't bother with correcting it in the actual interesting part of my post.
I think I've tried every DVD repair kit on the market. Even those that I figured probably were a hoax. Just because I have so many damaged DVD's that it was worth the risk I thought.
I have tried my damaged DVDs on many different players so I don't think that the laser is the problem.
I honestly think that DVDs are much more fragile than CDs.
Another thing which is weird with DVDs is that once it does find a bad spot it tends to lock up the system. I can't even skip forward or backwards.
The Internet is full. Go Away!!!
Actually, thinking about the physical packaging of the media, one thing I've been wondering since DVDs came along is - why the hell do all new media have to follow the exact same 12cm form factor of CDs?
It seems crazy, to me, that we have all these 12cm discs with identically sized holes in the centre, that could contain completely different kinds of data.
If I pick up a shiny 12cm disc, what should I play it on? my TV? My Hi Fi? Or maybe it's a data disc and only makes sense to my computer. In the future, I won't be able to tell by glancing at it whether a disc will be readable in my blue-laser DVD player, because it may be a UV disc.
Admittedly, my DVD player can play CDs, and I only need one optical drive on my PC - these are advantages, yes. And we're probably stuck with the 13cm shiny disc format for the forseeable future now. But shouldn't somebody have realised, back when DVDs were created, that maybe there ought to be a standard way of telling them apart from CDs?
And don't even think about getting me started on packaging design. I mean, it maybe makes sense to put movie DVDs into packages the smae height as VHS tapes, because people may have an existing investment in VHS storage in their living rooms. But in god's name, why would you package DVD-ROMs in the same sized boxes as VHS tapes? In an environment where people have storage space for CD-ROM-sized boxes, introduce a stupid, oversized box.
What sort of box are they going to use for blue DVDs? And what can we do to stop them?