Question

Consider a step index fiber with n1​=1.449,n2​=1.445, and a=25μm, please estimate the number of modes that can be propagated in this optical fiber. Assume that the wavelength is 1.5 micron.

Answer 1

The estimated number of modes that can be propagated in this optical fiber is approximately 41.

Step-by-step explanation:

In order to estimate the number of modes that can be propagated in the step index fiber, we can use the formula:

Number of modes = (2πa / λ) × √(n1^2 - n2^2)

where a is the core radius, λ is the wavelength, n1 is the refractive index of the core, and n2 is the refractive index of the cladding.

Plugging in the values given in the question, we have:

Number of modes = (2π × 25μm / 1.5μm) × √(1.449^2 - 1.445^2) ≈ 41

Therefore, the estimated number of modes that can be propagated in this optical fiber is approximately 41.