Question

Why refractive index of core is larger than that of cladding in optical communication?

Answer 1

In this case, it is the refractive index of the core with respect to the cladding. Since the sine of any acute angle lies between 0 and 1, its reciprocal will always result in a number greater than1. Thus, if n 2 , 1 is greater than 1, it means that the refractive index of thecore is greater than the cladding.

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