Question

Describe the construction and working of an optical fiber state.

Answer 1

Concept used:

1. When light strikes a medium with a lower index of refraction, the ray bends away from the normal, resulting in a higher exit angle than the incident angle.
2. For some critical incidence angle ${\theta }_c$, the exit angle will approach $90°$, and for incident angles larger than the critical angle, the total internal reflection will occur.

Optical fiber state:

1. Double layers of glass are used to make modern optical fibers. The inner fiber core ($8\mu m$) is encircled by cladding ($125\mu m$), a concentric core of lower index glass.
2. A protective layer surrounds the cladding. The core-cladding interface is where total internal reflection occurs.
3. The transmission of light along optical fibers is based on the total internal reflection theory. This is the underlying concept that allows the optical transmission to take place.
   

Construction:

1. Fiber optic technology is based on the ability to send a light beam along with a tiny fiber that has been carefully designed.
2. A glass or silica core makes up the core of a fiber optic cable. The optical fiber's core is surrounded by cladding, which is made of a comparable substance, such as glass or silica, and has a refractive index somewhat lower than the core.
3. The light going along the core undergoes total internal reflection and is thus confined within the core of the optical fiber, even when the cladding has a slightly higher refractive index.
4. A plastic jacket is applied on the outside of the cladding. This is used to shield the optical fiber from damage.
5. Furthermore, optical fibers are frequently bundled together and protected by an outer sheath. This not only adds to the protection but also keeps the optical fibers together.

Working:

1. A fiber optic cable's walls serve as numerous re-bounce points for light as it moves down the cable. With continual internal reflection like to a mirror, each light particle (photon) bounces down the pipe.
2. The light beam moves through the cable's core. The center of the cable and glass structure is called the core. A second glass layer that is wrapped around the core is the cladding. To retain the signals inside the core, cladding is present.