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I was thinking about the fact that in the last years I have never seen CDs and DVDs supporting writing/reading speeds higher than 52X and 16X, respectively.
Is this a commercial choice (i.e. manufacturers don't care about optical discs anymore and focus more on flash memories and SSD drives) or a technical limitation (i.e. optical drives cannot support higher writing and reading speeds)?
user1301428
Posted 2013-02-20T09:39:15.677
Reputation: 2 985
62
It's mostly a technical limitation. Put simply, if you spin the disk too fast it starts to become unstable and wobble around or even start to come apart under the sheer stress. At best this means read/write errors - and at worse means the possibility of it coming loose and causing damage.
At 52x speed, the disk is spinning at around 24000 RPM - at around 27000 RPM the disk would start to crack.
PhonicUK
Posted 2013-02-20T09:39:15.677
Reputation: 2 921
16
KenWood has played with CD-ROMs that use multiple lasers to read several places on the disc at once and then re-compose them into a single stream in firmware. They call this technology TrueX. You're able to read data faster at the same spin rate, but you need to use a more powerful laser (since it's being split), which requires more power and results in more heat.
Plutor
Posted 2013-02-20T09:39:15.677
Reputation: 541
The World's Fastest CD-ROM: Kenwood True-X – phuclv – 2020-02-13T14:17:33.570
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About a decade ago there were CD drives that used multiple laser beams to read 7 tracks at once for higher performance without having to spin the disk extremely fast. However they were expensive and apparently had reliability problems as well.
It's also worth noting that it isn't just a question of structural integrity of the disk at high RPMs, but also of noise.
Dan is Fiddling by Firelight
Posted 2013-02-20T09:39:15.677
Reputation: 2 677
6
15 years back...
"Will there ever be floppy disk with capacity more than 1.44 M?"
"Will there ever be floppy disk with higher read/write speeds?"
(For those who incase don't know, what floppy is: http://en.wikipedia.org/wiki/Floppy_disk)
Today, we don't care for an answer to above questions, simply for the fact that 'flop'pies have flopped.
Now, even CD-DVDs are approaching a similar state & have been replaced by Flash drives & Memory Cards. And in years to come, mechanical Hard Disks will follow the suite & will be completely replaced by SSDs.
The root lies in storage technologies involving mechanical movement/rotation are slow, error prone, require more power, make more noise, generate more heat & will be replaced by their non-mechanical counterparts & technology by next decade.
Viral Jain
Posted 2013-02-20T09:39:15.677
Reputation: 545
3
I personally doubt there will be a lot of work done in making the spin rate or RPMs faster on CDs or DVDs because the main reason to make them faster would be to be able to read or write the data to the disc then store it somewhere or perhaps send it to someone. However with the internet and network speeds getting faster, along with other technologies that allow us to share files to people of our choice, there is little need to make the discs spin faster as other technologies are already much faster than CD's or DVDs in terms of read and write speed.
If you look at the cost of a 2TB WD passport drive they cost around $100 and they fit in the palm of your hand, that beats discs any day for storage and speed, along with durability and portability.
I do think that having a CD or DVD available has its merits, like when you need an OS CD to fix an installation of an operating system, but for sending data there are faster and cheaper ways of doing that these days.
I just thought I would put my two cents in, hope I didn't upset anyone with this comment Cheers
Frank R
Posted 2013-02-20T09:39:15.677
Reputation: 306
3
Say, at 52x speed, the disk is spinning at around 24000 RPM The diameter of a cd is 11.5 cm Then the perimeter of a cd is 11.5 x pi = 36.13 cm
The edge of the cd rotates at 24000 rotations per minute, so the speed of the edge of the cd is 36.13 x 24000 x 60 = 52024763 cm/hr
This is 520247.63 m/hr = 520 km/hr = 323 mph
So how much faster do you want it to go?
patrick
Posted 2013-02-20T09:39:15.677
Reputation: 31
but cars are made of metals. CDs are made from plastic which are much more fragile. * A DVD's stronger tensile properties mean it can spin at up to 32,000rpm before serious problems arise, compared to 23,000rpm for a CD-ROM*
– phuclv – 2018-07-25T09:18:19.1701"How much faster do you want it to go?" Probably the same thing they were saying about cars 50 years ago when they reached 100 km/h :) – user1301428 – 2013-02-27T11:03:47.173
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I'm not enough of a technical expert to say this with extreme conviction, but I'm convinced that it's purely an economic issue. Yes, there are technical issues (several previous answers mention some really nasty ones) but technical issues have a way of disappearing when somebody has an economic incentive to make them go away.
And there's simply no economic incentive to develop faster optical drives. Optical media is no longer a primary means of getting data into computers. I can't remember the last time I used a CD or DVD to install software. It's easier to download it. On the rare occasions I need removable media (transferring network drivers to a system with a fresh OS install; using bootable media to install an OS) thumb drives usually make more sense.
My main laptop has a DVD drive that I've only ever used to watch movies — and it's plenty fast for that.
Isaac Rabinovitch
Posted 2013-02-20T09:39:15.677
Reputation: 2 645
Sure, technical limitations do tend to go away when there is enough money at stake. In this case I don't think that's the case, though--there's not that much advantage to faster transfer speeds. That would normally only be much of an issue to the sort of people that post here--and we have better options for throwing around big piles of data anyway. – Loren Pechtel – 2013-02-27T02:57:58.977
1@LorenPechtel How is that different from what I said? – Isaac Rabinovitch – 2013-02-27T06:33:19.890
There is SOME economic incentive--the casual user. It's just there's not ENOUGH. – Loren Pechtel – 2013-02-27T21:12:45.993
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I've seen many CD drives reading at 56x. So for the 52x speed, the answer is yes. But no more higher speed would be available
That's the theoretical speed and it's not easy to reach that value. Speed is highest at the edge of the disc, so you'll only see that maximum speed when reading a full disc at the end
phuclv
Posted 2013-02-20T09:39:15.677
Reputation: 14 930
This isn't much of an answer. If the links go dead, is your answer worth much more than a comment? – studiohack – 2013-09-27T01:09:59.280
2@studiohack: What I said is that 56x CD drives exist. Just provide the links for some example. If they go dead, there are still hundreds of them on google – phuclv – 2013-09-27T01:16:50.973
So the 72x CD models were never available in your universe? Interesting... ;) see: Kenwood 72X CD-ROM Review from year 2000
– David Balažic – 2016-03-21T15:17:56.567Your rpm numbers seem based on the 480 rpm of an audio CD. However, that is the speed when reading the inner edge, on the outer edge it's only 210 rpm. A 52x CD-rom drive only reaches its specified maximum transfer rate at the outer edge, so the maximum rpm is 52*210=10920 rpm. – Previous – 2016-10-01T13:48:41.790
4They could modify the disk in theory to suppor higher RPMs the problem of course is that they would create a new standard for a media that is slowly being discontinued. The simple fact is Blu-ray is the future, and most of the manufactures know that, so why waste money making a CD or DVD support faster burn times. You can already burn a double layer DVD in a few minutes. – Ramhound – 2013-02-20T12:08:24.657
3Yup, infact DVDs can spin faster than CDs before breaking for this very reason. Blu-rays however spin slower because the data density is much higher. If the data is more tightly packed, you don't need to spin the disk as fast to read data at the same rate. – PhonicUK – 2013-02-20T12:19:50.300
15The speeds of Blu-ray media will only get faster as the data density is increased. Eventually there will be a question on this website in 2023 that asks "Will there ever be faster Blu-ray disks and writers?" :-) – Ramhound – 2013-02-20T12:21:52.057
16@Ramhound Nah in 2023 it will be "Why does it still take 10 minutes to transfer a new language via BrainLink?" – PhonicUK – 2013-02-20T13:43:13.113
7Forget about
BrainLinkits all aboutBrainLink 2.0– Ramhound – 2013-02-20T13:49:07.8201@PhonicUK You're wrong about bluerays spinning slower than DVDs, just as a DVD's spin 3x faster than CDs at 1x, Bluerays base spin speed is 2x that of a DVD. A BR at 12x (fastest I see on Newegg) is spinning as fast as a 24x DVD (fastest at Newegg) or 72x CD. – Dan is Fiddling by Firelight – 2013-02-20T16:12:35.667
So I am. Although in either case the required rotational speed for a given data rate is slower than DVDs and CDs due to the increased density. – PhonicUK – 2013-02-20T16:15:54.280
You can see the effect of wobbling of CD spinning extremely fast in this video: Mythbusters - Exploding CD.
– MiKy – 2013-02-21T11:40:15.913@Ramhound: Blu-Ray may be the future, but that future may be short-lived, as streaming media take over. By 2023 we may look back on Blu-Ray as an interesting experiment that represented the last gasp of media consumption in physical form. – Robusto – 2013-02-21T13:34:49.543
@Robusto - Until the every person ( who has electronics ) is connected to the internet the physical product will exist. Based on the current rate governments are working towards that goal ( i.e. they are not working towards that goal ) we have nearly a decade until more then 90% of the world is connected to the internet. The internet at this point is approaching to be a right everyone should have just like "access to clean water, access to food, and access to shelter" is considered a right. – Ramhound – 2013-02-21T14:07:00.870
Mythbusters did a great show on CDs/DVDs breaking apart at high speeds showing the physical limitations of the media. – Chef Flambe – 2013-02-26T00:58:45.643
Respectfully disagree. Yes, the issues you describe would be difficult to overcome, but are they really insurmountable? I don't see it. More in my answer. – Isaac Rabinovitch – 2013-02-27T01:58:53.233