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Hollow Optical Fibres Can Now Process Signals
Ami_Chan writes: "According to Nature, researchers at Bell Labs have created a new type of optical fibre. This fibre is hollow, and can be tuned to different wavelengths of light using 'plugs of fluid' and temperature changes within the fibre. This allows the fibres to process signals as well as transmit them. The full article is here."
[tt]Optical fibres currently do the boring legwork in telecommunications. Soon these light-filled strands may play a more active role. Researchers at Bell Laboratories in Murray Hill, New Jersey, have created optical fibres that can be switched between different states that transmit light of different colours1. These fibres can process signals as well as carry them.
Devised by John Rogers and his colleagues, the new fibres are hollow. Perforated with channels thousandths of a millimetre across, each fibre looks like a bundle of drinking straws. Their tunable behaviour comes from plugs of fluid within that can be pumped back and forth.
These 'microfluidic fibres' combine the cheapness and robustness of conventional fibre optics with the functionality of more complex and expensive devices. Currently, when switches or transistors are installed midway along the length of a fibre, they can end up buried and inaccessible along underground or seafloor transmission lines. Breakdowns in such cases are understandably costly.
Wavelength-division multiplexing, for instance, is a common way of sending many optical signals down a single fibre simultaneously. Different signals, encoded in light beams of different colours, are unravelled at the receiving end using special filters or light sensors.
Microfluidic fibres could act as both transmission channel and filter, and could be switched to relay first one signal and then another - without all the separate paraphernalia that is otherwise needed to decode the signals.
The fluid plugs alter the fibres' light-conducting behaviour. Light travelling through the fibres' solid glass core changes when it passes through a region surrounded by fluid. Under certain conditions, this can make the fibre relatively opaque to light of a narrow band of wavelengths, so that the fibre filters it out.
The filtered wavelength can be tuned by altering the temperature of the fluid; this is done by a tiny electrical 'heater' wrapped like a sleeve around a short section of the fibre. The wavelength and attenuation of the filtering can be controlled using a second heater further down the fibre, to warm up the air in the channels. This pumps the liquid plugs further inside or outside the region where they become active as filters.
Rogers and colleagues anticipate that other arrangements of fluid plugs, heaters, pumps and so on will fulfil a variety of other functions that are needed in optical-fibre communication networks.
References
Mach, P. et al. Tunable microfluidic optical fiber. Applied Physics Letters, 80, 4294 - 4296, (2002).
[/tt]
I wonder if one of those fiber-optic lamps you can get would function as a CPU. . .
You are not the customer.
Now I just wish I wasn't all wacked out on a coke slurpee and sluggish from lunch so that I could think about the implications and actually say something intelligent.
perl -e 'print $i=pack(c5, (41*2), sqrt(7056), (unpack(c,H)-2), oct(115), 10)'
wouldnt this system be susceptable to distortion through vibration? if the line is bumped it would cause a shift in the fluid, if only a minute one, possiply distroying the signal. it would be interesting to se what measures bell labs has taken to account for this if amy at all.
I want 2D games back.
I'd be interested to know exactly how it works. The article talks in length about heat and fluid changing the light but either I'm missing something or it doesn't really say how.
Is it really changing the light or are they creating some kind of filter?
The Anti-Blog
It's probably just another hoax
</sarcasm>
Actually sounds like switches might start keeping up with the bandwidth. Although keeping fluid and tubes at exact tempratures can't be cheap. Think superconductors.
Arrogance is Confidence which lacks integrity. -- me
On the Lite-Brite product line.
...with a heat gun. So all I have to do is heat the fibre up and completely destroy data integrity? Sounds like a great idea.
Intelligence is like four wheel drive, having it just means you'll get stuck in more remote places.
Alright this does sound fascinating and all but fiber is already really expensive and so are filters for breaking down the transmission into it's composite "colors" but it seems to me that it wouldn't take much run of this new and presumably much more expensive fiber to pay for the filters.
Click here or here.
...they make nifty drinking straws!
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This sounds like it's based on the same technique used to make filters in the microwave band. By creating a transmission line with several appropriately spaced steps in the impedance, you can create a low-pass filter. With some more sophisticated branching of the line, you can make a high-pass or a band-pass filter. The technique relies on interference and reflection effects from the boundaries between the transmission line sections. I think they're doing the same sort of thing here; introducing fluid into the center of the line will change its refraction coefficient, which takes roughly the same role in the fiber that impedance does in a transmission line.
Would this type of wire be easier/harder to tap into than normal fiber optic wire?
GoatPigSheep, the 3 most important food groups
OK, I understand the researchers were doing very cool things that might have a whole range of interesting uses, but...
I thought the whole lesson of the Internet was that the network should provide connectivity only, with a bare minimum of built-in processing...
because, if you put processing into the network you are making fundamental assumptions about how the network is going to be used. In other words, processing within the network = optimizing for predetermined uses = locking out future evolution and outside innovation.
Shades of the old Bell Labs that were committed to circuit-switching and opposed to packet-switching!
"How to Do Nothing," kids activities, back in print!
As long as they're careful with it... don't want to open up any portals to "fluidic space;" we might get all sorts of horrible beasties coming through.
Karma: T-rexcellent.
"In related news Bell Labs has made first contact with a new race of being said to live in the fluidic space created within a new breed of fibre optics..."
*Condense fact from the vapor of nuance*
will fiber optic ever be changed to an analog version with the wave of the light being the transport of data rather than the flashing?
It seems that the data would be moved much faster if the sensors were able to pick up on individual light colors and waves rather than just on/off of the light. This would be able to work similar to how a modem works with diffrent tones producing diffrent characters, etc...
ps.
If this is already how fiber works than my understanding is just way off and please disregard.
Paying taxes to buy civilization is like paying a hooker to buy love.
Glass is technically NOT a liquid, this is a myth.
Like old windows that are heavier on the bottom than the top.. and people say it's because it flows over time.
It's not. It's because the glass process at the time did not produce nice, even panes of glass, and it made SENSE to put the heavy side down, M'kay?
The argument can be made that glass is fluid if you re-define what constitutes 'glass'. For instance, molten glass is obviously a fluid.
But glass, as in a window pane, or fiberoptic cable, is decidedly NOT fluid.
The whole point is: the ideal network is an unlimited broadcast network. Every host can see every packet, and we have unlimited bandwidth.
Another way to put it: bandwidth cures switching.
That said, that's not possible; we don't have it. We have to have a way to optimize the links we use.
This technique is based on photonic bandgap fibers. They were invented by Phillip Russell at Bath University (UK). These fibers contains a pattern of hollow channels that form the 2D equivalent of a multilayer mirror. Light can not travel in such a region. One channel in the middle of the matrix is missing, creating a defect state where the light can travel.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
...FIBER!!
Hrm won't this kind of be like the AI computers in the hyperion series which inhabit the medium of communication?
A rabbit in the hand is worth 4 in the cage
Why does everyone insist glass flows? IT DOESN'T.
Do you not listen? Old windows are not uniform because THEY NEVER WERE. They do not get worse over time.
Glass DOES NOT FLOW at room temperatures; there is not enough energy present to allow it to flow.
What does oil and water mixing have to do with glass flowing?
GLASS DOES NOT FLOW. IT IS AN URBAN MYTH. IT IS WRONG.
CUmulative thermal shock? You are inventing things out of thin air.
Once again.
GLASS IS NOT A LIQUID.