Which component of optical fiber primarily guides the light signal?

The core of the optical fiber is the primary component responsible for guiding the light signal. It is the central part of the fiber where the light travels, and it is made from a material with a higher refractive index compared to the cladding that surrounds it. This difference in refractive indices enables the phenomenon of total internal reflection, which is essential for keeping the light confined within the core as it travels along the length of the fiber. This allows the optical fiber to transmit data over long distances with minimal loss and distortion.

Other components serve important functions but do not guide the light signal. For instance, the cladding helps to maintain the light within the core by providing a reflective boundary. Meanwhile, the buffer coating provides physical protection to the fiber against environmental damage, moisture, and physical stress. The outer sheath serves a protective and insulating purpose but does not participate in the guidance of light.