FIBER OPTICS

What
A technology that uses glass or plastic threads to transmit data.a fiber cable consists of a bundle of glass threads to transmit messages modulated into light waves.

History:
As far back as roman times, glass has been drawn into fibers. Yet, it was not until the1790's that the French Chappe brothers invented the first "optical telegraph." It was a system compromised of a series of lights mounted on towers where operators would relay a message from one tower to the next. Over the course of the next century great strides were made in optical science.

How it's made:
Optical fibers are made of extremely pure optical glass. We think of a glass window as transparent, but thicker the glass gets, the less transparent it becomes due to impurities in the glass.

TYPES OF FIBERS

• Multi-mode fibers
• Single-mode fibers

Multi-mode fibers
The first to be manufactured and commercialized. Modes result from the fact that light will only propagate in the fiber cone diameter. Multi-mode fiber may be categorized as step-index or grade-index fiber.

Single-mode fibers
Single-mode fiber allows for a higher capacity to transmit information because it can retain the fidelity of each light pulse over longer distances, and exhibits no dispersion cause by multiple modes.

WHERE THEY CAN BE FOUND

• Hospitals
• Telephone lines

HOW

• Light travels in a straight line through the glass tube.
• The light never leaves until the end

THATS ALL!!!