In this article we will discuss about, what is TYPE OF LASER and their examples .A hundred years ago, Albert Einstein laid the foundation of one of the most revolutionary inventions of the twentieth century – LASER (Light Amplification by Stimulate Emission of Radiation).
His theory of stimulate emission of radiation,publish in 1917, stimulated and guided research endeavours towards development of a working LASER for the next 43 years culminating in the invention of the first operational LASER by Theodore Maiman in 1960. The term LASER conjures up images of incredible sources of light energy and magic light machines that can cut and drill metals, destroy satellites, read and send data, cool atoms, trigger fusion and perform complicate surgeries.
Lasers are, in fact, generators of light. It is base on the amplification of light by means of stimulate radiations of atoms or molecules. Different TYPE OF LASER developes in various research.
In 1917, Einstein did predict the possibility of such a stimulate radiation.. In 1952, Ch. Townes, J. Gordon and H. Zeiger in U.S.A, and N. Basov and A. Prokhorov in USSR, separately suggest the theory of generating and amplifying microwave oscillations. It leads to the invention of MASER(Microwave Amplification by Stimulate Emission of Radiation) in 1954. In 1960, Theodore Maiman of Hughes Research Laboratory synthesised the first laser using a ruby crystal. A. Javan, W. Bennett and D. Harriot of Bell Laboratory, using a mixture of Helium and Neon gases, in 1961, develop the first gas laser. In the same laboratory, L.F. Johnson and K. Nassu produce the first neodymium laser that ideally is the most reliable lasers available.The first semiconductor laser, was develop by R. Hall at the General Electric Research Laboratory in the year 1962.
TYPE OF LASER
Since the first LASER invented by Maiman in 1960, thousands of new LASERs have been
develop so far. Schawlow even made a joking reference to the “edible” LASER and the “drinkable” LASER.
LASERs are classifie in several ways such as the choice of the active material used for LASER action, mode of operation , power, efficiency and applications.Some well-known lasers are solid-state lasers,gas lasers (further classified ), semiconductor
lasers, liquid lasers, chemical lasers, dye lasers, metal-vapour lasers, free electron lasers, and
Raman lasers.On the basis of medium, these are further divided into: (a) Solid (b) Liquid (C) Gas
These solid-state lasers were the first-known lasers. They belong to the high-density gain media.Examples: Ruby laser, Glass laser, Fibre laser, YAG Laser, etc. Ruby laser: Ruby was the first laser. Theactive material use is Cr 3+ dope in ALO crystal. It is mostlyimportant for uses in holography. Glass laser: It is widely use in material processing and in the medical sector. They are used in nuclear fusion and in military application such as range calculation. Fiber lasers: It is used for fibre optic communication because optical signals travel longer distances with the least amount of loss.
Liquid Lasers solutions of certa and have high & The dyes used in scintillator dye, xan Is laser, the active media are forme by the ons of certain dyes dissolve in liquids such vater, alcohol. These dye lasers are lunable have high gain as compare to solid lasers. es used in this laser are polymethene dye, or dye, xanthenes dye, and coumarin dye.
Gas Lasers Gas lasers belong to low-density gain me According to the active medium, the gas lasers are
ther divided into atomic laser, ionic laser, and molecular laser. The optical quality is better because it is optically homogenous.
APPLICATION OF LASER
Within science, these are use for different applications, such as huge interferometric technique varieties, atmospheric remote sensing, holographic technique, raman spectroscopy. Laser-based light
Detection and Ranging (LIDAR) technology has applications in remote sensing, seismology, atmospheric physics and geology. After the laser invention in the year 1958, a large number of applications in the field of medical, military, scientific, and commercial laser have been develop. Some important applications are give below:
Some Other Important Lasers
Semiconductor Lasers It is a specially designed p-n junction diode, which emits coherent radiation in forward-biased condition. There are two types of lasers, i.e., homo Junction laser and hetero-junction laser. These emit lights almost anywhere in the spectrum from UV to IR. The advantage of this laser is that it is portable and easily controlled source of coherent. It is widely used in optical reading, high-speed laser printing, and in CD audio players.
This was the first laser ever develop in 1961 and the most widely used lasers. It is an atomic laser having four-level pumping schemes. The active medium is the mixture of 10 parts of Helium and 1 part of Neon. These are mostly used in the laboratories for barcode reading laser printing, These are used as reference beams in surveying for alignment of pipe line, etc.
type of laser eye surgery
Medicine and Surgery
Laser plays an important role in the field of medicines and therapies. Laser surgery has been extensively use in cosmetic surgery, i.e., removing tattoos, wrinkles, stretch marks, scars and hair Lasers use in dermatology are ruby, alexandrite and YAG specially. In eye laser surgery, Argon laser beam is focus on the desire point of the eye’s retina. In open eye surgery, YAG Laser use to remove cloud membrane. Techniques used include LASIK, which is use to correct short and long sightedness in version, by using exciter laser corona can be reshape. In dentistry, laser rays are vapouris to coagulated and close the small blood ves that wound surface is sterilise. Laser ang is a therapy in which excimer laser is catheter vapourises the plaques and thus artery. Lasers are use indestroying kian and gallstones. all blood vessels so í laser is insert in and thus opens thekidney stones and gallstone.