If they can make 1TB hard disk platters...

[TheDarkKnight]

Why don't we have 1TB blu-ray discs yet?

The eternal quest for infinite storage goes on. I was reading a product description for one of Segates 3TB hard disk drives. And it says it contains 3 1TB platters. And I was thinking, "Damn, that is cool." Now if they could only get that capacity on a blu-ray bd-r disc I would be happy.

Im guessing that the platters are not any bigger than a standard blu-ray disc. And I would think that a blu-laser would offer more precision as a reading device over those little mechanical moving heads that they use in hard disk drives.

So my question is, if the platters used in hard disks are no larger than a standard blu-ray bd-r disc and a blu-laser offers more reading precision than a mechanical hard disk, why in the hell don't we have 1TB blu-ray discs? What technology is allowing hard disk manufacturers to stuff a terabyte of info on a single platter and how long is it before we can get this to blu-ray? I want it NOW!

Edit: Being able to swap-out a terabyte of storage on demand with relative ease in less than 30 seconds would be awesome. Can I get a hell yeah?!?!!!

 

[Phynaz]

You're kidding, right?

 

[TheDarkKnight]

You're kidding, right?

Ummmm....no...did the question sound like I was kidding... What knowledge am I lacking in that you are apparently privy to? I have the brain of a chimpanzee so please enlighten me.

 

[Phynaz]

I have the brain of a chimpanzee

:thumbsup:

 

[TheDarkKnight]

:thumbsup:

Oh God, the neverending quest for people who want attention goes on as well...3,405 posts from this guy and they are probably all the same...You got me. Congrats!!! Now hopefully we can get on with the discussion

 

[TakeNoPrisoners]

Hard disks do not need to be very durable like a blu-ray disk. They are also made of metal and spin much faster then optical disks. They also have a mechanical head that reads the disks while optical disks use lasers. Hard disks are sealed to prevent dust from getting into the case and causing problems with reading.

The technology used to make hard disks is very sensitive and is not up to the task of being thrown around like you can do with your blu-ray disks.

Fingerprints and dust will ruin hard disk platters.

 

[Phynaz]

Oh God, the neverending quest for people who want attention goes on as well...You got me. Congrats!!! Now hopefully we can get on with the discussion

I can't. Intel shut down my CPU.

D:

 

[jwilliams4200]

Hard drives are magnetic, while blu-rays are optical. Totally different technologies.

A better question is why you think two totally different technologies should have the same storage density?

 

[TheDarkKnight]

Hard drives are magnetic, while blu-rays are optical. Totally different technologies.

A better question is why you think two totally different technologies should have the same storage density?

Yeah, different but same. I stated the reasons for my thoughts in the original message by choosing to point out the similarities between the two different technologies. You are replying by highlighting the differences. So back to my original question... Please read "TakeNoPrisnoers" reply if you wanna actually contribute something to the thread. Thank You.

 

[Red Squirrel]

One thing that would be interesting to see is cdrom drive size hard drives, like the old days, but with today's density. Imagine how big they could go. I could see that useful for server applications. I'm sure with today's technology a drive the size and thickness of a cdrom drive (so it fits in such a bay) would probably be over 5TB. Imagine 4 of those in raid 10.

I'm sure it's technologically possible to make a 1TB+ optical disk, the problem is, the slightest piece of micro dust, or it's bending, would throw everything off track so they would be very unreliable. Hard disk platters are in a semi air tight seal for a reason. Dust can't get in there, and if a tiny spec does get in, it will wreck havoc. They are also not very flexible at all compared to optical disks.

 

[Kusnierek]

Why settle for only 1TB?
http://www.digitaltrends.com/computing/japanese-working-on-a-disk-1000-times-larger-than-blu-ray/

 

[TheDarkKnight]

Why settle for only 1TB?
http://www.digitaltrends.com/computing/japanese-working-on-a-disk-1000-times-larger-than-blu-ray/

Now that is what I am talking about!!!!!!! YES!!!!! Get it done, son!!!

 

[Kusnierek]

Keep in mind however that this sort of thing, while sounding really cool, may not come into fruitation. 25TB discs sound like a pipedream, and the fact that they say it can be done with common Titanium oxide also sounds too good to be true. Even if they did this successfully, it would be nothing more than a science project to show that they can. At our level of technology, they might be able to fabricate a disc and show it off, but the equipment needed to read it, or even REPLICATE the disc might be several orders higher in cost.

 

[jwilliams4200]

Yeah, different but same.

No, not the same at all. Optics is completely different than magnetism. Plastic is different than metal. The technologies are completely different. It would be a coincidence if they happened to have the same storage density.

Blu-ray laser diodes have a wavelength of about 400nm. The minimum possible spot size for focusing light is about half a wavelength. So the best density you can achieve is about 2.5e13 bits/m^2 , while the usable area of a 120mm optical disc is about 0.01m^2, giving you about 2.5e11 bits per layer per disc. If the ECC is 80% efficient, that comes to 25GB. Which is the capacity of a single-layer blu-ray disc.

With PMR, a magnetic platter can store 600Gbit/in^2, which comes to 9.3e14 bits/m^2, more than 30 times the density that can be achieved per layer with blu-ray.

 

[jwilliams4200]

Keep in mind however that this sort of thing, while sounding really cool, may not come into fruitation. 25TB discs sound like a pipedream, and the fact that they say it can be done with common Titanium oxide also sounds too good to be true.

Definitely too good to be true. Those sorts of announcements have been coming out for decades. It used be "holographic storage" that was touted all the time.

Usually scientists make these lofty claims after someone in the lab had some minor breakthrough and they want to talk it up in order to get funding. The scientists that make these claims rarely understand all of the engineering that is required to turn something they demonstrated once in the lab into a viable, mass-produced technology.

Anyway, just look at the date on that article, and note that nothing has come of it in more than 2 years.

Assuming that the proper reading and writing equipment is also developed, the new synthetic metal could be a giant leap in optical storage.

You know what happens when you assume...

 

[TheDarkKnight]

Somebody will get this done. I don't know who will get it done first but I am hopeful its coming soon.

http://www.digitaltrends.com/computing/sonys-blu-ray-replacement-to-store-1tb-on-a-single-disc/

Thanks to Kusnierek for the earlier post which led me to this one.

I would just buy a 3tb hard disk but since the prices were doubled and the warranties were cut in half...Im thinking....no....

 

[Selenium_Glow]

With SSDs becoming more affordable and popular by the day, I was thinking that there is no point in pursuing high density in Optical media and Hard Drives. However, there is also a limit to the maximum density that can be achieved on flash storage.

Then I remembered this thing i read about a long time ago ->
http://en.wikipedia.org/wiki/Millipede_memory

Millipede is a non-volatile computer memory stored on nanoscopic pits burned into the surface of a thin polymer layer, read and written by a MEMS-based probe. It promises a data density of more than 1 terabit per square inch (1 gigabit per square millimeter), which is about the limit of the perpendicular recording hard drives.

Yes, this is not an economically feasible idea yet... but if you are looking far ahead, then check all possibilities

 

[thelastjuju]

This thread is bizarre

Only thing I'll throw in.. the possibility of compression methods becoming more and more advanced.. like say, an even more sophisticated, "future" version of the .mkv, where these outrageous file sizes will be a thing of the past.

its pretty amazing how much you can compress a full bitrate bluray down in file size, while still retaining so much original quality with this type of format. So hopefully these types of advancements will take place as well.

 

[jwilliams4200]

Only thing I'll throw in.. the possibility of compression methods becoming more and more advanced.. like say, an even more sophisticated, "future" version of the .mkv, where these outrageous file sizes will be a thing of the past.

Not going to happen. The H.264 AVC compression already used for blu-rays is near the limit of what is possible without introducing artifacts. Yes, some people reencode the video to compress it more, but that invariably introduces artifacts that people with high quality displays can notice. Perhaps H.265 may be able to improve on that by a factor of 2 or so, but I suspect it will be noticeable in some cases (i.e., someone could tell the difference between the same segment at H.264 and H.265 in a blind test).

So, the best that we are looking at in the future is an additonal factor of 2 over the current H.264, and even a factor of 2 may be difficult to achieve while maintaining the same quality.

 

[Phynaz]

Please read "TakeNoPrisnoers" reply if you wanna actually contribute something to the thread. Thank You.

Great attitude for somebody that is asking for help with something

 

[serpretetsky]

Im guessing that the platters are not any bigger than a standard blu-ray disc. And I would think that a blu-laser would offer more precision as a reading device over those little mechanical moving heads that they use in hard disk drives.

I can agree with the first one, platters are not any bigger, since i've seen them in person.

Now I am not engineer, but I dont know why you assumed the second one. Do you have some evidence for why laser technology should be more precise?

I mean... as you point out, hard drives are indeed more dense than optical discs. Why do you think laser burning is more precise?

 

[BrightCandle]

Predominantly they have dramatically different storage densities because:
1) A Blue ray disk is placed into a drive bay and spun with normal air pressure around, this causes the disk to wobble quite considerably and while the laser will auto focus on the moving disk this increases the necessary size of the dot of information. It in turn also means the reading head must be further away than in a hard drive.

This has other impacts like the size of the head and the accuracy with which it can be placed are all much higher in a hard drive because these things are the limitations not the wobble of the disk.

2) A hard drive is using magnetic fields to store bits in a metal coating. The magnetic directions used don't involve as much of a physical change as the blue ray process of literally heating the area until it darkens. Thus you find that a single bit can be considerably smaller in metal and magnetic fields than in a plastic coated material that is dark or reflective.

3) CD roms have a durability layer over the actual data of the disk which is effectively clear plastic. But this plastic is reflective and refractive and it impacts the focussing of the laser beam on the bytes.

These I would say are the major factors determining the dramatically better storage density of a HDD compared to a Blue ray, but there are many other reasons as well.

 

[Red Squirrel]

With SSDs becoming more affordable and popular by the day, I was thinking that there is no point in pursuing high density in Optical media and Hard Drives. However, there is also a limit to the maximum density that can be achieved on flash storage.

Then I remembered this thing i read about a long time ago ->
http://en.wikipedia.org/wiki/Millipede_memory



Yes, this is not an economically feasible idea yet... but if you are looking far ahead, then check all possibilities

HDDs still strive in high capacity and high I/O systems though, because of their unlimited writes. I would never use a SSD as my server's data storage volume no matter how big or cheap they get. SSDs are great as an OS drive or other low write application, but HDDs still strive at large data writes especially in a raid configuration.

My fear is that SSDs completely replace HDDs and HDDs become an "enterprise product" only then they'll be artificially extremely expensive. I still rely on HDDs for all my server storage needs at home. SSDs for OS drive only.

 

[Cerb]

This thread is bizarre

Only thing I'll throw in.. the possibility of compression methods becoming more and more advanced.. like say, an even more sophisticated, "future" version of the .mkv, where these outrageous file sizes will be a thing of the past.

MKV is a nearly universal video container format. It's great, but has nothing to do with compression. It will be happy as can be with entirely uncompressed streams.

BrightCandle basically answered the OP.

 

[jwilliams4200]

BrightCandle basically answered the OP.

Answered incorrectly. I already explained the physics of why using a blue laser has a limit to the storage density obtainable per layer (half-wavelength focusing). The mechanics of the disc has little to do with it, since blu-rays are already at the fundamental limit for 400nm light.