Fiber Optics By: Herlina Lim Chem 323 Analytical Instrumentation

Chronological History In 1870  John Tyndall demonstrated that light follows the curve of a stream of water pouring from a container. In the 1950's  more research and development into the transmission of visible images through optical fibers. In 1966  Charles Kao and George Hockham proposed the transmission of information over glass fiber.

What is Fiber Optic? A thin and very fine strand of glass or plastic that carries light transmissions over long distance.

Three main parts of Fiber optics 1 st part : Core (placed in the centre of the fiber. This is where the light will travel) 2 nd part : Cladding (outer optical material that reflects the light back into the core) 3 rd part : Buffer Coating (plastic coating that protects the fiber from damage and moisture)

The principle : Total Internal Reflection Lights travel through the core by constantly reflecting from the cladding as the angle of incidence always greater than critical angel. Since cladding does not absorb any light from the core, the light wave can travel great distances.

Fiber-Optic Relay System Optical Transmitter : produces light signals Fiber optic cable : conducts the signals over a distance Optical Receiver : receives the light signals

Two types of fiber optic cable Single Mode Fiber Multi Mode Fiber one mode of transmission Carry higher bandwidth than multimode fiber but requires a light source with a narrow spectral width Used in telephones and cable TV Multiple mode of transmission In long cable runs, multiple paths of lights can cause signal distortion at the receiving end  unclear and incomplete data transmission Used in computer networking

Advantages compare to copper wires Less expensive Thinner Higher carrying capacity Light and digital signals Low power Non-flammable Flexible Coiled Copper Wire Rod

Bronchoscopes Bronchoscope

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