Fiber optics use thin strands of glass called optical fibers to transmit light signals over long distances. Light travels through the core of the fiber, which is surrounded by cladding that reflects the light down the length of the fiber. Fiber optic systems include a transmitter that produces light signals, the optical fiber that carries the signals, and a receiver that interprets the signals. Fiber optics have advantages over metal wires like lower costs, higher data capacity, and less signal degradation over long distances.

1. How Fiber Optics Work
You hear about fiber-optic cables whenever people
talk about the telephone system, the cable TV
system or the Internet. They are also used in
medical imaging and mechanical engineering
inspection.

2. What are Fiber Optics?
Fiber optics (optical fibers) are long, thin strands
of very pure glass about the diameter of a human
hair. They are arranged in bundles called optical
cables and used to transmit light signals over long
distances. If you look closely at a single optical
fiber, you will see that it has the following parts:
*Core - Thin glass center of the fiber where the
light travels
*Cladding - Outer optical material surrounding the
core that reflects the light back into the core
*Buffer coating - Plastic coating that protects the
fiber from damage and moisture

3. How Does an Optical Fiber Transmit
Light?
The light in a fiber-optic cable travels through the
core (hallway) by constantly bouncing from the
cladding (mirror-lined walls), a principle called total
internal reflection. Because the cladding does not
absorb any light from the core, the light wave can
travel great distances.

4. A Fiber-Optic Relay System
Fiber-optic relay systems consist of the following:
*Transmitter - Produces and encodes the light
signals
*Optical fiber - Conducts the light signals over a
distance
*Optical regenerator - May be necessary to boost
the light signal (for long distances)
*Optical receiver - Receives and decodes the light
signals

5. Advantages of Fiber Optics
Compared to conventional metal wire (copper
wire), optical fibers are:
1.Less expensive
2.Thinner
3.Higher carrying capacity
4.Less signal degradation
5.Light signals
6.Low power
7.Digital signals
8.Non-flammable
9.Lightweight
10.Flexible

6. How Are Optical Fibers Made?
1.Making a preform glass cylinder
2.Drawing the fibers from the preform
3.Testing the fibers