Applications of Lasers in Communication, Space, Surgery, Military...
The ingenious principle of laser was first worked out in 1958 by Charles Townes of Columbia University. He made use of this principle a few years earlier in 1953 to invent a very similar device- maser where microwaves are used instead of light waves. Hence laser is an optical maser. The first successful laser using a large synthetic ruby crystal was built by Teodore H Maimann in 1960. With the discovery of laser man's control of light has been and will continue to extend to an unpredictably large and diverse number of applications in scientific field.
(i) Communication :
Since light from the laser is coherent it can theoretically carry messages in the same manner as comparatively low frequency carriers. The frequency of the laser is so high that each message or band of frequencies is a very small percentage of the carrier frequency. Hence a large number of messages can be sent. It can accommodate millions of television channels.
(ii) Space exploration :
Rockets and satellites can be efficiently controlled by laser beam.
(iii) Measurement of large distances
Distance between earth and other planets can be accurately measured by laser beam because it is highly collimated.
(iv) Welding
The laser can be used effectively for spot welding. It possible to weld a joint even after the joint has been sealed inside glass envelope.
(v) Hole drilling
A sharply focused laser beam can be used to cut holes in diamond and other hard materials,
(vi) Surgery
(a) Tooth drilling : The beam destroys by vaporization the dark decayed spot.
(b) Eye - Surgery : Eye - tumors can be removed and detached retina of human eye can be welded by low power laser beam. The Lasik surgery is nowadays used in treating the defects of eye by correcting the shape of the cornea of the eye using laser beam to get sharp image of an object exactly on the retina of the eye.
(c) Cancer treatment : Laser beam can remove some cancerous cell instantly, accurately, and without pain or bleeding.
(vii) Thermonuclear fusion
Laser can he used to trigger a thermonuclear fusion.
(viii) Military applications
The laser beam can be used to destroy an attacking missile in space. Moreover it can be used as 'death-ray gun' to destroy enemies.
(ix) Photography
Laser beam can be used to produce three dimensional images without the use of lenses. This process is called Holography.
(x) Science
(i) Chemical reactions can be accelerated by exposing it to the laser beam.
(ii) Laser can he used to study Raman effect.