Monday 26 October 2009

How Fibre Optics works?

Water can be directed from one place to another by confining it within a pipe. In the same way light can be directed from one place to another by confining it within a single glass Fibre.

The light is kept within the fibre by total internal reflection. The amount of light which can be carried by a single Fibre is very small so it is usual to form a light tube tapping a few thousand Fibres together. On great advantage of such a light tube is flexibility; it can be ties in knots and still function. However since total internal reflection only occurs when light is going from a medium to a less dense medium, it is necessary to coat each fibre with glass of a lower refractive index. Otherwise light would leak from one fibre at their points of contact.

Light tube can be used to bring light from a lamp to an object, thus illuminating the object. A second light tube can then used to carry light from the illuminated object to an observer, thus enabling the object to be seen and photographed. The procedure has been used to photograph the digestive system the reproductive system and many other parts of the human body. In the case of the light tube carrying light from the object to the observer, it is vital that the individual fibres in the tube do not cross each other, otherwise the image will become garbled. Like radio waves, light waves are electromagnetic. However, their shorter wavelength and higher frequency means that a single light beam can carry far more telephone conservations at one time compared with a radio wave.

In the case of long fibre cables it would be necessary to incorporate a device to boost the intensity of the light to make up for losses due to absorption. Nevertheless the system has great potential for the communication industry, including the possibility of transmitting pictures over long distances.

The reason why light bends when going from one medium to another is because of the change of velocity.

What is Modal Analysis

Vibration can occur in any physical system. Properties of the system are the frequencies at which vibration occurs and the modal shapes whi...