LASER: Light Amplification by Stimulated Emission of Radiation is a mechanism of using a powerful, intense narrow beam of light that can produce intense heat when focused at close range for emitting nondiverged monochromatic electromagnetic radiation.

There are available lasers using various substances like argon, helium-neon, neodymium, ruby,carbon dioxide and krypton.

LASER and Medical applications in microsurgery, cauterization, online monitoring and diagnostics as well as the development of new therapheutic methods.

The broad spectra of the fs laser pulses give the advantage to use the same laser pulses for diagnostic applications like the optical coherence tomography (OCT).

It is used in treating in visual operations like vitreo-retinal surgery (correcting the aberrations in eyes), refractive surgery (the principle of getting rid of glasses with the help of a laser surgery (fs-LASIK)), treatment of presbyopia (increasing the flexibility of the crystalline lens), destroys antibiotic-resistant infection.

Medical lasers are also widely used for various types of cosmetic surgery.

Dentistry is another branch of medicine that has benefited tremendously from laser technology.

LASER is used inUltrafast Physics the applications of ultrashort laser pulses increase rapidly is the physics. Welding and Cutting (the beam of a laser can be focused to a dot with extremely high energy density for welding and cutting).

The highly collimated (the automobile industry makes extensive use of carbon dioxide lasers with powers up to several kilowatts for computer controlled welding).

Surveying and Ranging (Helium-neon and semiconductor lasers have become standard parts of the field surveyor’s equipment).

LASER in the Garment Industry (Computer controlled laser garment cutters can be programmed to cut enormous number of pieces just in a few cuts).

LASER is used in hardening or annealing metals.

Barcode Scanners Supermarket scanners use helium-neon lasers to scan the universal barcodes to identify products. The laser beam bounces off a rotating mirror and scans the code, sending a modulated beam to a light detector and then to a computer which has the product information stored.

Laser in Communication The lasers have significant advantage because it is more nearly monochromatic and this allows the pulse shape to be maintained better over long distances. If a better pulse shape can be maintained, then the communication can be sent at higher rates without overlap of the pulses.