Refraction and fiber optic cable diameter

Hello there,
I'm wondering if there is any restricting reason why fiber optic cables are not made thicker. Regardless of the practical applications, is there any reason you can't make a fiber optic cable that is only 2m long but 2cm thick (compared to the normal 0.0125 cm thick)?
Does width of the high index core make a difference, and does the width of the low index coating make a difference in regard to total internal reflection?

To sum it up, is there any physical reason why fiber optic cables can't be made thicker?

Thanks for reading,
JJ
 
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berkeman

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Hello there,
I'm wondering if there is any restricting reason why fiber optic cables are not made thicker. Regardless of the practical applications, is there any reason you can't make a fiber optic cable that is only 2m long but 2cm thick (compared to the normal 0.0125 cm thick)?
Does width of the high index core make a difference, and does the width of the low index coating make a difference in regard to total internal reflection?

To sum it up, is there any physical reason why fiber optic cables can't be made thicker?

Thanks for reading,
JJ

ps. I'm wondering if you have to take into account the wave particle duality of light when working with fiber optics or is it mostly particle behavior?
Welcome to the PF. Are you aware of the differences between single-mode and multi-mode fiberoptics?

http://en.wikipedia.org/wiki/Fiber_optics

And are you aware of the concept of "dispersion", where the path lengths for multi-mode fibers (especially as wide as you are asking about) indroduce different delays for different ray traces? What effect would dispersion have on high-bandwidth optical signals?
 
Thanks for answering and good points berkeman,
I am not particularly concerned with transmitting data or signals, and so I believe that dispersion wouldn't play a bad role as long as the light was a guided ray the whole time. You could say that I want to be able to use the fiber optic cable like a snake light, where you could put light in one end of the cable and receive light out of the other end, like an extension cord for a flash light. I believe the thickness would require multi-mode, it would allow more light sources can be used.
 

Andy Resnick

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Light pipes are different than fibers. Fibers are (usually) significantly longer- many kilometers- for one thing.
 

Integral

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If you want a thicker fiber optic, just bundle up a bunch of smaller ones.
 
If you want a thicker fiber optic, just bundle up a bunch of smaller ones.
That could possibly work. A light pipe (Thank you Andy Resnick) is what I believe the term is what I am looking for.
 
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Andy Resnick

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It depends on the application- do you need it to be flexible? Are you trying to image?

Liquid light guides have diameters up to 8 mm. I've seen rigid light guides with diameters over 2 inches, but I don't recall who made them.
 
I'm not trying to image, just pass light from a flashlight into one end and out the other to be used for light to see. Rigid works, flexible is better. Light guides are the closest I've seen so far. I can adapt from the light guide concept and go from there.
Thanks for pointing me in the right direction Andy.

This is what I was looking for.
http://www.lumatec.de/e_superlite/e_superlite.htm [Broken]
 
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