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FrozenGate by Avery

have 405 nm diodes hit a wall?

I

ixfd64

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About two years ago, we saw Blu-Ray burners steadily increase in power. However, this trend seems to have stopped ever since they hit 12x in late 2009. So my question is: have 405 nm diodes hit their reached their current limit?

I do believe this is the case for DVD burners as they haven't increased in speed ever since they reached 24x several years ago. This is probably because 650 nm diodes can't go much beyond 300 mW or so without being multi-mode, whereas optical drives require single-mode operation.

Does the same go for Blu-Ray lasers?
 
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ixfd64 said:
About two years ago, we saw Blu-Ray burners steadily increase in power. However, this trend seems to have stopped ever since they hit 12x in late 2009. So my question is: have 405 nm diodes hit their reached their current limit?

I do believe this is the case for DVD burners as they haven't increased in speed ever since they reached 24x several years ago. This is probably because 650 nm diodes can't go much beyond 300 mW or so without being multi-mode, whereas optical drives require single-mode operation.

Does the same go for Blu-Ray lasers?
Click to expand...

Hoping daguin will chime in here.

I asked the same question a while back and his answer was something along these lines.

12x is the physically fastest the discs can spin inside of the drive without them shattering due to g-forces. However, as more layers are added to discs, their diodes power may have to increase to compensate, so we're not screwed yet :)
 
From Wiki

There are mechanical limits to how quickly a disc can be spun. Beyond a certain rate of rotation, around 10000 RPM, centrifugal stress can cause the disc plastic to creep and possibly shatter. On the outer edge of the CD disc, 10000 RPM limitation roughly equals to 52× speed, but on the inner edge only to 20×. Some drives further lower their maximum read speed to around 40× on the reasoning that blank discs will be clear of structural damage, but that discs inserted for reading may not be. Without higher rotational speeds, increased read performance may be attainable by simultaneously reading more than one point of a data groove, but drives with such mechanisms are more expensive, less compatible, and very uncommon.
Click to expand...

So we'll either start seeing multi-diode burners (as in 2x BR diodes combined in a burner) or higher powered single diodes.

Lase
 
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405s on a technological basis are still advancing. They now exceed the 1W range in terms of power.

However, I believe its the whole "internet TV" craze that has severely slowed the blu-ray market since it can be had cheaper, and with more convenience. There is simply no more "drive" to make faster disc writers.
 
I'd say it seems like bluray has hit its limit. Technically there could be advances in more layers on a disc and such, but those would only be marginal increases in storage space and not keep up with requirements.

Writeable bluray has been problematic for the consumer market from its start, due to high prices for media. This continues to be the case, and it looks like flash memory cards will be cheaper by the gigabyte than bluray discs soon enough.. and they dont require an optical drive either.

In the long term this will be a problem for laser builders as both dvd-rw and bluray come to their end of life and drives and sleds will not be available forever. Lets hope the projector industry will fill the gap.
 
Benm said:
I'd say it seems like bluray has hit its limit. Technically there could be advances in more layers on a disc and such, but those would only be marginal increases in storage space and not keep up with requirements.

Writeable bluray has been problematic for the consumer market from its start, due to high prices for media. This continues to be the case, and it looks like flash memory cards will be cheaper by the gigabyte than bluray discs soon enough.. and they dont require an optical drive either.

In the long term this will be a problem for laser builders as both dvd-rw and bluray come to their end of life and drives and sleds will not be available forever. Lets hope the projector industry will fill the gap.
Click to expand...

Stock up now :)
 
Benm said:
Writeable bluray has been problematic for the consumer market from its start, due to high prices for media. This continues to be the case, and it looks like flash memory cards will be cheaper by the gigabyte than bluray discs soon enough.. and they dont require an optical drive either.
Click to expand...

Good riddance to optical drives! Though I'll miss having a good source of laser diodes. Hopefully pico projectors pick up the slack.
 
Meatball said:
405s on a technological basis are still advancing. They now exceed the 1W range in terms of power.
Click to expand...

While 405 nm diodes have been driven to that power, they weren't designed for it. A diode lasing at that level won't have a very long life expectancy!

Or am I missing some new type of diode on the market?
 
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