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By,Xavier Prathap.WI BSc, MPC.

LASER

LASER is an acronym for ,LASER is an acronym for ,

Light Amplification by Stimulated Light Amplification by Stimulated Emission of RadiationEmission of Radiation

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History of LASER

 In 1917, Albert Einstein first theorized the possibility of Lasers.

The first working laser was created by Theodore Maiman on May 16th, 1960 at the Hughes Research Laboratory in California.

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Spontaneous Emission

Excited atoms normally drop to Lower Excited atoms normally drop to Lower Energy Level SpontaneouslyEnergy Level Spontaneously

Photons are uncorrelated and unidenticalPhotons are uncorrelated and unidentical Incoherent lightIncoherent light

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Stimulated Emission

Excited atoms Excited atoms are forced to are forced to emit by another emit by another matching matching photonphoton

Photons are Photons are correlated and correlated and identicalidentical

Coherent lightCoherent light

Principle of Laser Population Inversion.Population Inversion.

The phenomenon of exciting the atoms, so The phenomenon of exciting the atoms, so that, there are more number of atoms in the that, there are more number of atoms in the Higher Energy Level than in the Lower Higher Energy Level than in the Lower Energy LevelEnergy Level

Optical PumpingOptical Pumping

The method of achieving Population The method of achieving Population Inversion is known as Pumping. And, one Inversion is known as Pumping. And, one of the types of pumping in known as of the types of pumping in known as Optical Pumping.Optical Pumping. 6

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Lasing Action Diagram

Optical

Pumping

Ground State

Excited State

Metastable State

Spontaneous Energy Emission

Stimulated Emission of Radiation

Ruby Laser

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Properties of Laser

Laser light is highly monochromatic.

Laser light is extremely directional.

Laser light is spatially coherent.

Laser light is extremely intense and bright.

Applications of Lasers

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Laser are used,

In optical communication.In guiding missiles to desired destinations.To scan information on bar codes.To make holograms.In making Integrated Circuits.In CD playersIn surgery.In industries to cut and weld strong metals.To measure distances very accurately.To store and view 3D informations.

THANK YOU

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