why no distortion in optical fibre signal when i bend the wire

[shirish heller]

optical fibres work on the principle of total internal reflection...for that angle of incidence has to greater than a particular critical angle...now my TV transmission from my d2h antenna to my settop box is also via optical fibres .....

so if i bend the wire completely the angle of incidence will not be good enough and the ray of light would simply move out

buy nothing happens when i do so WHY???

Also,my headphone cables are optical fire ones this means data is communicated through light signals(by PAM) but i do not see any sorce of light in my headphones(lasers or such)....??????

 

[OunaLypse]

maybe they are not optic fibres, double check! :thinker:

 

[dick_freebird]

Probably you cannot bend a jacketed FO cable to a tight
enough radius that the internal reflection is badly-enough
compromised for the link to fail.

The signal is passed digitally and over the short haul you
probably have a huge signal-strength surplus. You might
still recover digital data after losing 90% of the optical
power. You would have to cleave, not bend, the fiber to
lose that much.

These days optical links have become highly integrated
little modules. You might not recognize the piece, and
the guts may resemble a 3D stack of chips (mod/demod,
VCSEL/PIN diode, optical interface) but you'd have a
hard time disassembling the "nugget" to see.

Or, "optical fire" could be marketing BS referring to the
day-glo jacket of a plain old copper wire. Who knows?

 

[chuckey]

If they use infra red for your headphone link you will not be able to see this.
Frank