A principle called total internal
reflection allows optical fibers to retain the light
they carry. When light passes from a dense substance into
a less dense substance, there is an angle, called the critical
angle, beyond which 100 percent of the light is reflected
from the surface between substances.
Total internal reflection occurs
when light strikes the boundary between substances at an
angle greater than the critical angle
Fiber optics makes use of certain special conditions, under
which all of the light encountering the surface between
two materials is reflected, to reduce loss.
Light can travel for long distances through fiber optic
cables . In a process known as total internal reflection
, light travels through a fiber optic cable by reflecting
off the cable’s inner walls , even when the cable is
bent. Although a fiber optic cable is transparent , almost
no light escapes from it. Most fiber cables are ,made by
pulling pure glass into long , fine strands.
Advantages of fiber optic cables over normal wires:
Fiber optics can carry much more information in a much smaller
1.No interference from electromagnet fields result in "clearer"
2.No electrical resistance.
3.No hazard of electrocution if cable breaks.
Uses of Optical fibers:
Endoscopes uses optical fibers, which is used to view the
Information can be carried in the form of optical signal
Some decorative lamps and water fountains uses optical
If you are still unclear about the concepts, please refer
the animation below.
The animation also consists of
- Sectional view of fiber optic cable
- Detailed ray diagram about the propagation of light
inside optical fibers
- Detailed explanation of Total internal reflection taking
place inside the cable
- Analysis of ray path if the cable is bent sharply
- Application of optical fibers
- Data communication using the cable