Laser applications

From ArticleWorld

Today lasers have became tools of choice for scientists and engineers alike and have extensive application in various streams of scientific research, manufacturing, strategic military programs and surgical medication, etc.

Civil applications

Some important applications in scientific research are in spectroscopy, lunar range finding, photochemistry, laser cooling, nuclear fusion, as finderscope for telescope and microscopy.

• In spectroscopy laser beam of very high spectral purity is used to detect very small concentration of atoms and molecules.

• In case of lunar laser ranging the time of flight between retrorelfector array on moon and a large telescope on Earth, was used to measure the earth – moon distance with great accuracy.

• In photochemistry, femtosecond laser pulses are used to induce a chemical reaction and investigate its mechanism as well.

• In case of laser cooling, ions confined in a trap are slowed down by shining them with a laser beam at a particular wavelength, thereby retarding them to very low temperature / velocity and thus producing the famous ‘Bose – Einstein condensate’.

• Lasers are used for causing nuclear fusion as well by ‘inertial confinement’. In this process, very high intensity laser pulses are made to impinge upon tritium – deuterium pellets. This leads to great hydrostatic compression of the pellet causing fusion of the nuclei.

• Laser is used as a pointer attached to a telescope and thus facilitates locating the celestial body of interest with ease for observing by the telescope.

• Lasers are finding use in microscopy as well with confocal laser scanning microscope very much poised to give a very good competition to scanning electron microscopes.

Military applications

In military applications, lasers are integral part of strategic defense programs.

• Chemical lasers with very high pulse power are being looked upon as a potent tool to destroy aircrafts / missiles much before the target and preferable in enemies terrain itself. The idea of the “Star War” was to use ground based or space (satellite) based high power lasers to destroy ICBMs just after launch. However, the associated problems are maintaining the laser beam quality against scattering and refraction as it travels long distances through inhomogeneous atmosphere.

• Another idea was to use high power X-ray lasers, pumped by atomic fission i.e. an atom bomb, for the same purpose. However, these ideas were essentially dropped after “Star War” program was cancelled.

• The most common military application of lasers is in aiming the enemy targets with laser attached on the rifles’ / pistols’ barrel, to dazzle enemies in the battle ground and to guide munitions launched from an aircraft very precisely to the target.

• Due to versatile properties of laser it was considered to replace guns in its early days. Although that is not feasible today, still some handheld laser guns capable of blinding, though prohibited, are still with some countries.