Question

Why are fibers birefringent

because of the chemical makeup of the fiber

because the fiber is a natural fiber

because the fiber has long range order

because the fiber has a refractive index greater than 1.52

because the refractive index is less than 1.52

Answer 1

Inevitable manufacturing imperfections in optical fiber leads to birefringence, which is one cause of pulse broadening in fiber-optic communications. Such imperfections can be geometrical (lack of circular symmetry), due to stress applied to the optical fiber and/or due to bending of the fiber.

Answer 2

Because of the chemical makeup of the fiber.

Step-by-step explanation:

The birefringence is the difference between the refractive index of a fiber in a direction at parallel to the fiber axis and in a direction at right angles. It is caused by asymmetric core shape for the two axes, and majorly one of the manufacturing imperfections. It helps in controlling polarization property inside the fiber.