Total Internal Reflection Confusion

AI Thread Summary
Total internal reflection in fiber optic cables relies on the critical angle, which varies based on the materials used. Even small angles can result in internal reflection due to the design of optical fibers, which have a thin diameter and specific bending limits. The confusion arises from the misconception that the critical angle is a constant; it is actually influenced by the refractive indices of the materials involved. Understanding this variability clarifies how signals can still be transmitted effectively even at seemingly small angles. Overall, the properties of the fiber material play a crucial role in maintaining signal transmission.
ferrarilover2000
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Hi,
I'm new here...
I already read about how the signals are transmited through the fibre optical cables... total internal reflection

But what I don't understand is the another day I was scribbling it on a piece of paper (the total internal reflection that is)... I noticed that from the way I drew it, some had very small angles and it dosen't look like it's bigger than the criticle angle...

If that is so than the signals would have stopped right there and couldn't be transmited anymore... :confused:

Oh Me God please someone... save me! :rolleyes:


Thanx :-p
 
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It seems to me that you think of the critical angle as some sort of constant.

Let me just say that the critical angle is a variable and therefore is able to differ. Optical cables are structured so that even small angles are internally reflected.
 
Hmmm...
Thanks for the reply recon...

So you are saying that the material for the fibre optical cables have a smaller critical angle?



Thanx :D
 
I'm, not sure I understand how your scribbles looked. Remember that fibers have a very thin diameter and that there's a limit to how much they will bend.

The critical angle depends on what materials you use to make the fiber.
 
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