Print 33 comment(s) - last by alifbaa.. on Feb 25 at 11:18 AM

The photograph shows the far-field pattern of the world's first gallium nitride (GaN) nonpolar blue-violet laser diodes. The bright spots illustrate clear lasing modes. Photo courtesy of UCSB Solid State Lighting and Display Center
The highest capacity optical storage devices and DVD recorders all use blue lasers -- and offer only poky write times in the range of 2X to 4X. New high-powered blue lasers could change that in a hurry

Nichia Corp. of Japan has broken the speed record for writing Blu-ray discs.
The company has announced a new blue-violet laser that can fill up a 54GB double-layer disc at more than 10X record speed. Currently-shipping Blu-ray and HD-DVD format disc recorders are mostly of the 2X variety, though a few can boast 4X speed.

The difference from today’s 2X record times to 10X, based on future availability of the high-speed lasers, will be remarkable, according to blue laser expert Steven DenBaars, professor of materials and co-director of the Solid-State Lighting Center at the University of California Santa Barbara. As an example, today’s 2X blue-laser-based DVD recorders require about 50 minutes to write a disc containing a full-length DVD movie, DenBaars said, while a 10X laser could accomplish the task in about 10 minutes.

The key to faster write times lies in the power of the laser, according to DenBaars. Nichia’s new blue-violet semiconductor laser diodes can reportedly operate at 320 mW (milliwatts), while the average consumer grade blue laser devices commercially available today are in the range of 20mW. “Writing speed is totally dictated by the output power,” DenBaars said. “The more power you have, the faster you can spin the disk.” Higher power lasers take less time to burn microscopic areas of the disc, creating the digital ones and zeros that are the building blocks of optical data storage. Faster burn times allow the disc to be rotated at a higher speed. A 2X device can sustain a write speed of only 8.99 Mbps, while a 10X laser disc recorder can achieve a writing velocity of 44.9 Mbps, DenBaars said.

While the new high speed lasers will eventually improve the usability of blue laser storage, making applications such as archival storage on the devices more feasible, DenBaars described the innovation as more “evolutionary” than revolutionary. DenBaars was part of the team of UCSB researchers that recently announced another breakthrough in blue laser technology that could increase power even further.

The UCSB team, led by blue laser inventor and former Nichia Corp. researcher Shuji Nakamura, recently demonstrated the world's first nonpolar blue-violet laser diodes. According to DenBaars, the technology could eventually produce blue laser diodes that operate in the range of 500 mW. However, commercial availability of the nonpolar blue lasers is still two to four years away, he said.

Comments     Threshold

This article is over a month old, voting and posting comments is disabled

10x != 5 x 2x
By Yawgm0th on 2/23/2007 10:06:48 PM , Rating: 2
As an example, today’s 2X blue-laser-based DVD recorders require about 50 minutes to write a disc containing a full-length DVD movie, DenBaars said, while a 10X laser could accomplish the task in about 10 minutes.

Burn time does not decrease linearly with burn speed increases. The disc does not burn at the fastest speed available, and will have to work up to the fastest speed. That's on top of initialization and finalization of the disc. Although with Blu-Ray and HD-DVD it will be at the top speed for a higher percentage of the burn, they're still not able to have burn times decrease linearly with burn speeds.

I think someone is exaggerating, messing with numbers to too high a degree, or is simply misinformed. I'm guessing one of the former two, given that they author of this article is paraphrasing an expert when providing that information. I'd imagine it would be more like 48 minutes burn time at 2x and 13 minutes at 10x.

RE: 10x != 5 x 2x
By ted61 on 2/23/2007 10:25:53 PM , Rating: 2
Now that a math wizard showed up, tell me how to measure velocity in Mbps!

Math is not really my thing and I can never really tell when these guys are just being salesman with a pitch or they are giving me the facts.

RE: 10x != 5 x 2x
By Garreye on 2/24/2007 12:24:59 AM , Rating: 2
Wouldn't the velocity of the disk actually change depending on where on the disk you are wiriting?...It will spin faster when reading data near the center of the disk, right?

RE: 10x != 5 x 2x
By daftrok on 2/25/2007 12:23:49 AM , Rating: 2
You are thinking in terms of tangential velocity (linear) and not angular velocity (circular). The tangential velocity will be faster but the angular velocity will remain the same. In other words, if the Earth revolves once in 24 hours, the surface of the core of the Earth will also take 24 hours to revolve once.

RE: 10x != 5 x 2x
By Suomynona on 2/25/2007 6:09:05 AM , Rating: 2
While what you say is correct (for the Earth) the CD does not have a constant angular velocity

Instead the tangential velocity for each point is alway the same in the moment the laser is writing there.
(The angular velocity must be increased so that write speed stays constant since the write density is always the same)

Since the lenth you write to is I(v dt) v must be constant to have a constant write rate (same lenth passed in the same time).
-> v = w*r must be constant
-> w must increase while r is getting smaller.

Sorry for the bad explanation but my english isn't very good.

RE: 10x != 5 x 2x
By alifbaa on 2/25/2007 11:18:19 AM , Rating: 2
Actually, I thought your explanation and your English were both excellent.

RE: 10x != 5 x 2x
By Jedi2155 on 2/24/2007 7:55:44 AM , Rating: 2
Perhaps the power of the current laser is so low that they are still using a CLV rather than CAV?

RE: 10x != 5 x 2x
By Yawgm0th on 2/24/2007 3:56:37 PM , Rating: 2
It doesn't really matter that much for the purposes of this conversation. It will not burn at a constant speed for the entirety of the burn no matter what, and 10x will never be five times 2x in terms of actual burn time.

I hope they make a version..
By PLaYaHaTeD on 2/23/2007 4:29:19 PM , Rating: 4
..that's waterproof. My pet shark is having a mid life crisis, and needs a more powerful laser strapped to his head.

RE: I hope they make a version..
By Gatt on 2/23/2007 5:34:49 PM , Rating: 2
...All I asked for was a frikken shark with a frikken Blu-Ray strapped to it's head! Is that too much to ask for?

By ted61 on 2/23/2007 5:54:29 PM , Rating: 2
Can any of math wizards tell me how reading velocity in Mbps is going to affect the chain rule.

I wonder what the derivative of a velocity of an Mbps is?

RE: Velocity
By Hyperlite on 2/23/2007 8:50:01 PM , Rating: 2
i've been doing way too much calc lately too. =(

By jay401 on 2/24/2007 12:26:29 PM , Rating: 2
It'll be nice to have faster DVD write times. 8x is still fairly slow.

RE: good!
By Sivar on 2/24/2007 5:48:05 PM , Rating: 2
If you are thinking of ordinary DVD write times (not HD DVD), I believe the current limitation has more to do with the rotational velocity of the discs than the laser. DVD-sized discs start to get wobbly and difficult to manage when they are rotated much past about 12000 RPM.
This is one reason why 15000RPM hard drives have smaller platters than your usual 7200RPM drive, and they are manufactured with much higher precision.
This will probably be a limitation of the HD-DVD and BD-ROM once everything else catches up.

Write "Times"?
By Great Googly Moogly on 2/25/2007 5:34:11 AM , Rating: 2
Umm, is it only me or shouldn't that be write speeds ? In my world, write time is inversely proportional to write speed.

RE: Write "Times"?
By Yawgm0th on 2/25/2007 6:39:41 AM , Rating: 2
Indeed, it should be write speeds. Increased write speeds decrease write times, but they are not the same thing. 10x is a measurement of speed, not time.

Wicked Lasers
By codeThug on 2/23/2007 6:06:02 PM , Rating: 2

I don't care too much about the storage potential here. I'm waiting for to offer a 500mW blue/violet hand-held.

ucsb ftw!
By EnzoFX on 2/23/2007 10:57:39 PM , Rating: 2
=p my school makes the news again, cool.

By Egglick on 2/24/2007 4:40:07 AM , Rating: 2
Pretty, I guess. I wasn't even aware they were selling blue-laser burners yet, or that people were buying them this early in the game.

If someone's upset because they can't burn 25GB+ of data in 10 minutes, they need to take a step back from life. Maybe join a yoga class or something.

By andrejfavia on 2/24/2007 5:07:26 PM , Rating: 2
When I click on the link, I get the following javascript alert message as the page loads:

"The page at says:

Cannot Display release.

Invalid record number."

I did a quick search through these comments under the text "invalid record" and came up with nothing; I suspect that this is a just recent issue. What's going on?

By Phlargo on 2/25/2007 10:07:35 AM , Rating: 2
Is the dailytech readership getting clever? Or are they just on their periods? Highest sarcasm:post ratio I've seen yet. SomethingAwful's got nothing on us!

By Scabies on 2/23/07, Rating: -1
RE: hmm...
By Hare on 2/23/2007 5:14:44 PM , Rating: 3
ReadyBoost BRD-RAM, anyone? Yeah, not likely...
Readyboost benefits from fast accesstime not actual throughput. BRD would be terrible as a ReadyBoost media.

RE: hmm...
By smitty3268 on 2/23/2007 5:31:09 PM , Rating: 2
Even throughput is only around 5.6MB/s, which is quite a bit worse than a hdd. And like you said, Readyboost exists to speed up latency which I'm sure is absolutely horrible on any kind of drive like this that was designed for long non-random reads.

RE: hmm...
By Gatt on 2/23/2007 5:33:00 PM , Rating: 2
Unfortunately, that's 44Mbs, mega-bits/sec. More like 5.5 Mega-Bytes/sec(I think, if I did my math right).

RE: hmm...
By goku on 2/23/2007 6:56:16 PM , Rating: 2
LOL, slower than current CDR speeds.... tsk tsk... (52X=7800) which is approximately 7.6MB/s...

RE: hmm...
By v3rt1g0 on 2/23/2007 7:26:41 PM , Rating: 5
It seems the author messed up and used Mb instead of MB.

HD-DVD would be ~30GB for dual layer.
359.2 Megabits/sec (44.9 MegaBYTES/sec) over 10 minutes is 26.94GB.
If the 44Mb/sec were written 44MB/sec, the numbers come out correct.

RE: hmm...
By Ringold on 2/23/2007 5:35:50 PM , Rating: 2
Heat pollution?

Could double the power of the laser and still not be anywhere near 1 watt. In typical systems that burn 200 to 300 watts continuously I'm going to take a shot and say 'no'.

But just guessing.. watch me be wrong.

RE: hmm...
By Dactyl on 2/23/2007 8:19:40 PM , Rating: 2
Could double the power of the laser and still not be anywhere near 1 watt.
Wrong. It would be somewhere near 1 watt.

ichia’s new blue-violet semiconductor laser diodes can reportedly operate at 320 mW (milliwatts)

Double the power of one of these lasers, and you have 640 mW, which is .64 watts--64% of a watt--which is somewhere in the neighborhood of 1 watt. Scientifically speaking, it's about two doors down.

RE: hmm...
By Ringold on 2/23/2007 11:03:33 PM , Rating: 2
I suppose I'm pessimistic by nature. You'd take .64 watts and (correctly) round it to one, where as I'd look at it and say it's .36 watts short, or almost half a watt short. Cup is just always half empty on a rainy day with me I suppose. I concede your point.

RE: hmm...
By Farfignewton on 2/24/2007 10:36:44 PM , Rating: 4
I think stating that I make somewhere near $1000 a week when it's actually $650 MIGHT cause people to say I have a financial reality problem. But hey, 50% more and I'm practically there. Scientifically speaking. ;)

RE: hmm...
By timmiser on 2/25/2007 6:34:39 AM , Rating: 3
Last Saturday night I took out this girl on a date. I asked a scientist friend of mine and he said she was a full blown, hot & sexy, blue eye blonde 10. However when I put her picture up on Hot or Not, she only rateed a 6.4. What gives? Should I dump her or should I go with what the scientist said and keep believing she is a 10. Of course, my scientist friend, who has never had a girlfriend before, might round any girl up to a 10. Need some assistance on this one please.

RE: hmm...
By jtesoro on 2/25/2007 8:25:33 AM , Rating: 4
Not to turn this site into a personals page, but if you post a link to her pic I'm sure you'll get more assistance than you'll need. :)

But in terms of Hot or Not, in my opinion what matters is what YOU think.

"Game reviewers fought each other to write the most glowing coverage possible for the powerhouse Sony, MS systems. Reviewers flipped coins to see who would review the Nintendo Wii. The losers got stuck with the job." -- Andy Marken

Copyright 2016 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki