lasers

It is an acronym for Light Amplification By Stimulated Emission Of Radiation . It is a process by which we get a coherent, highly monochromatic and perfectly parallel beam of light. Lasers may also be called as optical masses. It has been invented and developed in 1959. The laser..

It is material in which the laser action is made to take place. It may be solid, liquid or gas. Many lasers are named after the material used e.g. ruby laser, He-Ne laser, CO 2 laser, Nd: YAG laser etc. The most important characteristic ..

The smallest lasers used for telephone communication over optical fibres have as their active medium a semiconducting gallium arsenide crystal about the size of a pin-hea..

Ruby Laser - In 1960, T .H. Maiman constructed the first laser using a Ruby crystal. Ruby is a crystalline form of silica(Al 2 O 3 ) with a slight natural doping of chromium. It has the following advantages for being used as a laser. (i) It is a solid having suitably a..

Atoms and Nuclei..

The laser is an acronym for Light Amplification by Stimulated Emission of Radiation. The laser has been invented and developed in 1959 and 196..

Microsurgery is any operation done with the aid of microscopes. Surgeons work with spectacle - mounted magnifiers or with microscopes. Using this technique, surgeons can remove adenoma, tumours of the pituitary gland, without damaging the gland itself. Neurosurgeons, ear and eye surgeons all rely o..

A laser beam departs from strict parallelism only because of diffraction effects, determined by the wavelength and the diameter of the exit aperture. Light from other sources can be made into an approximately parallel beam by a lens or a mirror, but the beam divergence is much great..

This property is related to the parallelism of the laser beam. As for star light, the size of the focused spot for a laser beam is limited only by diffraction effects and not by the size of the source. Flux densities for focused laser light of 10 1 5 W cm - 2 are ..

Laser Light is Highly Directional - A laser beam departs from strict parallelism only because of diffraction effects, determined by the wavelength and the diameter of the exit aperture. Light from other sources can be made into an approximately parallel beam by a lens or a mirro..