Question
Download Solution PDFIn a multimode fiber (step index), number of modes passing at an operating wavelength of 1300 nm are 1000, the refractive index of the core is 1.50 and that of the cladding is 1.48. The value of core diameter is:
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
The number of modes propagating in a step-index fiber can be estimated as:
Where V is the mode volume given as
Where d is the fiber core diameter and λ is the wavelength of the optical source, n1 is the refractive index of core and n2 is the refractive index of the cladding.
Calculation:
N = 1000
V = √2000
d = (44.7 × 1300)/3.14 × 0.244
= 75.8 μm
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