In fiber optics is the thickess of the cladding important?

[fisico30]

Hello Forum,

a fiber optic cable has two components: a core and a surrounding layer called cladding.

The core has an index of refraction n_cor sligthly larger than the cladding core c_clad.
This allows total internal reflection to take place. The difference in index is small to avoid large chromatic dispersion.

The size (diameter) of the core is important (relative to the input wavelength) because it determines the propagating modes.

How about the thickness of the cladding layer on top of the core? Does it matter?
It does not seem so...

Thanks
fisico30

 

[eljose79]

Dear fisico30,

Thank you for bringing up this interesting topic about fiber optic cables. As you mentioned, the core and cladding components are essential for the total internal reflection to occur, which is crucial for the functioning of the cable. The size of the core is indeed important as it determines the propagating modes, but the thickness of the cladding layer also plays a significant role in the overall performance of the cable.

The main purpose of the cladding layer is to provide a lower refractive index compared to the core, which helps to confine the light within the core and reduce the loss of light through the sides of the cable. The thickness of the cladding layer affects the amount of light that is confined within the core, which can ultimately impact the signal transmission and quality.

In general, a thicker cladding layer will result in a lower amount of light being confined within the core, which can lead to higher signal loss and decreased performance. On the other hand, a thinner cladding layer can result in higher levels of light being confined within the core, which can improve the signal transmission and reduce loss.

Therefore, the thickness of the cladding layer is an important factor to consider in the design and manufacturing of fiber optic cables. It must be carefully chosen to ensure optimal performance and minimize signal loss. I hope this helps to answer your question.