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What Are Polarization Maintaining Fibers? - http://www.fiberoptics4sale.com/wordpress/what-are-polarization-maintaining-fibers/
What is Polarization Maintaining Fiber? - http://www.youtube.com/watch?v=7rrb-_Iin-g
Principle of operation - Special purpose fiber fiber - http://en.wikipedia.org/wiki/Optical_fiber
Multimode fibers fibers - http://www.rp-photonics.com/multimode_fibers.html
The basic of fiber optic cable (single mode and multi mode) - http://www.arcelect.com/fibercable.htm
Single mode vs Multi mode fiber optic cable - http://www.multicominc.com/active/manufacturer/multicom/Fiber%20Optics/singlemode-multimode.html