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What is "near-field" optics?
 

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It's just vaporware until you can actually buy a product based on the technology. Considering how long other competing technologies have been in development, it will be amazing to see any real world products based on this technology anytime soon.
 

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Joe, I agree. Huge amounts of money have been "flushed" on this technology. Silicon Valley, the home of the hard disc drive has seen several companies (Terastor, Quinta come to mind) boom and bust trying to commercialize this technology. Classic near field recording is like MO with a flying head. People also tried to use "optically assisted writing" in hard discs. This used a magnetic material that would only change polarity when heated by a laser. The idea was that you could write smaller features with this technique than with a regular inductive head on a "normal" hard disc. MR read heads have the responsivity to read smaller features that what can be currently written.


This kind of announcement doesn't mean that commercial product will be available any time soon.


- Mike
 

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This is maybe less than vapor ware. I don't consider a new recording technology vapor ware until there is at least one Hollywood proposal to cripple it. ;)


- Tom
 

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With the Blu Ray consortium recently putting out a new press release, and the competing consortium continuing it's work, this thing has as much chance of producing pre-recorded movies for you and I as bubble memory.


Mark
 

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Quote:
By using "near-field" optical technology, the 100-gigabyte disc stores more than any other similar product in the world. The super-sized disc will be used at home to store large movie or music files, according to Tsai.
Is there a "regular" disc that holds less. Will the people at the store ask you if you want to "super-size" that DVD?
 

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Discussion Starter · #8 ·
While I can understand everyone's stance on this announcement, I for one, am glad that the technology is being researched and that there is still healthy competition for high capacity optical media. This can only be mean good news to HDTV fans, as not even Hollywood can ignore the potential of these high capacity discs.
 

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Quote:
Originally posted by miimura
Classic near field recording is like MO with a flying head
Can someone please explain what this is? Thanks.
 

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Perhaps these researchers should try the 'back door' approach apparently being used by makers of this 100-GB holographic disc . That is, introduce hardware aimed initially at the broadcast industry and other professional applications, as one firm did at this spring's broadcaster's convention (an early model).


A stab at that quote, dsegelstein: MO is magneto-optic recording, which can be heating a disc material with a laser, altering its properties so that reflected light from a readout laser is changed. Such a recording can be erased optically. The flying head describes how your computer's hard drive works, magnetically, with the read/write head 'flying' very close (near) to the disc surface. Noticed there's tons of hits on this topic with a net search. -- John
 

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Quote:
While I can understand everyone's stance on this announcement, I for one, am glad that the technology is being researched and that there is still healthy competition for high capacity optical media. This can only be mean good news to HDTV fans, as not even Hollywood can ignore the potential of these high capacity discs.
tomwid -


You are of course correct. All new advancements in this area can only help HDTV and we should probably be a bit more enthused.


I guess a lot of us have just become somewhat skeptical and jaded because of the huge ratio of technology announcements vs actual products.


But I never really believed we would have economical home-writeable DVD's either and yet we now take it for granted. So there is hope, but interminable delay. ;)


- Tom
 

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Quote:
Originally posted by John Mason
A stab at that quote, dsegelstein: MO is magneto-optic recording, which can be heating a disc material with a laser, altering its properties so that reflected light from a readout laser is changed. Such a recording can be erased optically. The flying head describes how your computer's hard drive works, magnetically, with the read/write head 'flying' very close (near) to the disc surface. Noticed there's tons of hits on this topic with a net search. -- John
To be more specific, classic Magneto-Optic recording uses an optical pickup structurally similar to a DVD or CD pickup. There is a lens that is suspended about a millimeter away from the spinning disc and focuses the laser through the disc substrate. In MO the laser heats a particular layer in the media so that it is susceptible to a magnetic field. A coil introduces a large magnetic field and alternates the polarity to record, but only the heated spot changes properties. When reading, polarization optics can detect the difference between the two different states created by the alternating magnetic field.


Near Field recording is a technique to focus a laser to make a very small spot. You can use this small spot to do MO recording or Optically Assisted Writing. Optically Assisted Writing is similar to MO except that the laser heat allows the media layer to change magnetic property instead of optical property and is then read back with a MR head like a hard disc. This allows very narrow tracks to be written. In either case, the recording layer must be on the first surface and the lens must be VERY close to the recording layer. They use flying heads so that the lens is held at a very consistent distance from the disc. This requires that the head be manufactured within a very tight tolerance. This tolerance is not required in CD/DVD/MO because the optics and the servo system actively hold the lens at the right distance to focus properly. The fact that the recording layer is on the first surface makes it sensitive to dust and other contamination, not to mention the possibility of contamination "crashing" the flying heads. So, removable media is not really practical. IMHO, this is one of the reasons why it was not possible to commercialize. That, and the rapid capacity advances in hard drives killed off the competitive advantage of using it in "fixed" configurations.


- Mike
 

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Near-field optics is where you get the imaging optics REAL close to your imaging medium. Think of a scanner in reverse, except instead of line of sensors, you have a very small point source, that lays down a very small track of data. We're talking Nano-stuff here. HNick
 

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Thanks for the explanation!
 

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As an optoelectronics engineer, I know a little about this. HNick is the closest to correct. Near field as compared to far field means image plane vs. Fourier transform plane, or Hygen Fresnel plane at infinity. What they mean by near field writing is imaging a source laser or laser array onto the media as compared to far field where the sources are focused. Focusing vs. imaging are entirely different. Take for example a telecentric imaging system, or the classic 4f system. The far-field is in the center at 2f and the near field is at 4f, at a distance farther away from the source than the far field image.
 

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Quote:
Originally posted by trbarry
This is maybe less than vapor ware. I don't consider a new recording technology vapor ware until there is at least one Hollywood proposal to cripple it. ;)


- Tom
Tom, you kill me, I am such a fan of yours....
 

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I was on Mars last week. What are you talking about? I have some red rocks for sale if you'd like in Classifieds. I also have some new Martian buddies on my IM list.


:)


Mark
 
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