How can light travel for a large distance through cables made of glass and moreover carry information and data with it, total internal reflection comes to our aid here. This animated physics topic gives in-depth information about Optical Fibers and is very useful for teachers, students and industry.

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 cable.
1.No interference from electromagnet fields result in "clearer" connections.
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 internal organs

Information can be carried in the form of optical signal

Some decorative lamps and water fountains uses optical fibers

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

• Application
  
  
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