Possible to design a flawless CD writer that used the same laser system as Kenwood's TrueX?

[Howard]

I was thinking, if you can read several areas of a CD at once, wouldn't it be possible to merely strengthen the lasers and turn the drive into a writer?

I know this would require a bit more precision than status quo, but we wouldn't need to spin CDs as fast.

 

[Evadman]

I believe this was already discussed.

The problem IIRC is that the way CD's are written with the pits and high points ( along with being writeen from the center ) it would be nearly impossable to get the tracks to line up enough to be readable.

<edit>
Bah, I can't find it.

 

[glugglug]

The problem is CDs are written in a spiral, rather than a clean track/sector format.

Once you burn your initial 7 loops of the spiral, you'll have a hell of a time getting the burning for the next 7 loops to start in the exact right spot.

It could happen on DVDs though.

 

[grant2]

Originally posted by: glugglug
The problem is CDs are written in a spiral, rather than a clean track/sector format.

Once you burn your initial 7 loops of the spiral, you'll have a hell of a time getting the burning for the next 7 loops to start in the exact right spot.

It could happen on DVDs though.

It seems strange to me that you think you could multi-laser burn a DVD, but not a CD, when DVDs have a much tighter spiral...

 

[glugglug]

DVD's aren't a spiral, they are laid out in ring shaped tracks like every other form of computer disc (besides CDs)

 

[grant2]

glugglug time for you to hit whoever's been feeding you those lies 🙂

here's a beginner tutorial into how DVDs are designed

 

[grant2]

BTW, there's no TECHNICAL reason a multi-laser setup couldn't be used to write "true-x" to a CD... but the engineering required to ENSURE the integrity of the burn is so high, and current writers are so fast, that there's no economics case for it.

However, since dual-layer DVDs may require 2 lasers to burn anyways, you may see a device that uses them simultaneously (if dual-layer DVD burners are ever made)

 

[dejitaru]

My Starcraft CD shattered when I put it in my 40x drive 🙁

BTW, there's no TECHNICAL reason a multi-laser setup couldn't be used to write "true-x" to a CD... but the engineering required to ENSURE the integrity of the burn is so high, and current writers are so fast, that there's no economics case for it.

Four lasers, seperate controls. You could write "approximately" to the disc and throw extra data on it for error correction. Quick and dirty.

Aren't the spirals on CD-R media prewritten? I thought that's why they were iridescent.

Do you have a full DVD format specification?

 

[dejitaru]

Or you could have the lasers in series (right next to each other), each writing to the next spin. Four lasers writing in parallel, each to its own loop.
You should be able to roughly calculate the number of bits for the next iteration.

Reading about the Kenwood thing, it doesn't actually use multiple lasers, it uses multiple beams to catch any read errors so that it doesn't have to on the next rotation, hence the "true x." If you did use multiple lasers, each split into multiple beams, that would be real cool stuff (potentially 1500x drives).

Then again, why not do this with hard drives if it's so perfect?