Upload
srivaralakshmi
View
149
Download
0
Tags:
Embed Size (px)
DESCRIPTION
Leaser beam technology description and applications
Citation preview
Welcome
Leaser Beam
TechnologyPresented By:
M.Sri vara lakshmiNarayana E Techno School
KKD-RR Pet
LASER; Light Amplification by Stimulated Emission of Radiations.
What is LASER
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.
History
In 1917, Albert Einstein established the theoretical foundations for the laser in the paper Zur Quantentheorie der Strahlung.
In the Soviet Union, Nikolay Basov and Aleksandr Prokhorov were independently working on the quantum oscillator.
Laser Physics
A helium-neon laser at the Kastler-Brossel Laboratory at University Paris 9. The pink-orange glow running through the center of the tube is from the electric discharge. This glowing plasma is excited and then acts as the gain medium.
Helium-neon laser
Stimulated emission
The energy of an electron orbiting an atomic nucleus is larger for orbits further from the nucleus of an atom. Thus, electrons are found in specific energy levels of an atom.
Types and operating
principles
Chemical lasers Chemical lasers are powered by a chemical reaction permitting a large amount of energy to be released quickly.
Fiber lasers
Laser amplifiers, where the light is guided due to the total internal reflection in a single mode optical fiber are called fiber lasers.
Excimer lasersExcimer lasers are a special sort of gas laser powered by an electric discharge in which the lasing medium.
Semiconductor lasers
Semiconductor lasers are diodes which are electrically pumped. Recombination of electrons and holes created by the applied current introduces optical gain.
Uses
Medicine: Laser healing,, kidney stone treatment, eye treatment.
Industry: Cutting, welding, material heat treatment.
Military: Guiding munitions, missile defence, electro-optical countermeasures alternative to radar.
Research: Spectroscopy, laser scattering, laser interferometry,, laser capture microdissection.
Product development: laser printers, optical discs, barcode scanners, thermometers, laser pointers, holograms.
Law enforcement: fingerprint detection in the forensic identification field.
Laser lighting displays: Laser light shows.
Cosmetic skin treatments: acne treatment, and hair removal.
Safety
Today, it is accepted that even low-power lasers with only a few milliwatts of output power can be hazardous to human.
People working with lasers can protect their eyes with safety goggles which are designed to absorb light of a particular wavelength.
Warning symbol for lasers
Laser warning label
As Weapons
The lowest power lasers can potentially be used as weapons through their ability to produce temporary or permanent vision loss when aimed at the eyes.
REFERENCES
Bertolotti, Mario -The History of the Laser, Institute of Physics.
Bromberg, Joan Lisa -The Laser in America,, MIT Press.
Csele, Mark -Fundamentals of Light Sources and Lasers, Wiley.
CONCLUSIONLaser technology can be used in both good and bad waysUsing technology in a proper way gives us best results.To improve technology we have to:
Invest more on researchEncourage improving minds of children
Questions please!!!