Self Study World

Coherence In Physics Two waves are said to be coherent if they have the same frequency (or wavelength) and are in phase ( or have a constant phase difference between them). The coherence of a wave depends on the characteristics of its supply. The light produced by lasers is coherent light. Light from light bulbs or the sun is incoherent light. A high  coherence means high fringe visibility with excellent contrast (i.e. good black and white fringes or black and whatever color the light is) and low coherence means washed-out fringes and zero coherence means no fringes. Another necessary condition (for waves to be coherent) is therefore that both waves travel at the same speed. It can be well understood from Fig. (1) and (2). Fig. ( 1) shows a typical beam of light waves from an ordinary source traveling through space. It is a concept that establishes the limits within which a real light source can be considered ideal. It is a measure f the correlation that exists betwee

Semiconductor  any of  a category  of solids (such as germanium or silicon) whose electrical conductivity is between that of a conductor  which  of an insulator in being nearly as great as that of a metal at high temperatures and nearly absent at low temperatures A semiconductor is a substance, generally a strong concoction component or aggravate, that can lead power under a few conditions yet not others, making it a decent medium for the control of electrical current. Its conductance changes relying upon the current or voltage connected to a control cathode, or on the power of illumination by infrared (IR), unmistakable light, bright (UV), or X beams.  The particular properties of a semiconductor rely upon the debasements, or dopants, added to it. An N-type semiconductor conveys current for the most part as adversely charged electrons, in a way like the conduction of current in a wire. A P-type semiconductor conveys current dominatingly as electron lacks called gaps. An opening has a

Theory Of Hologram Holography is a technique employed to make three-dimensional images. The size of the object can range from large cars to small particles on the micrometer scale. Holography originates from the work of the British/Hungarian scientist Dr. D. Gabor. He tried to improve the resolution of his electron microscope in 1947, using a mercury arc lamp, the incoherent light source resulted in distortions in his images. These images he called holograms after the Greek words “holos” meaning “whole or entirely” and “gram” meaning “message or recording”. He developed a technique by which three~ dimensional images of an object can be recorded and reconstructed by a wavefront construction device with the help of a highly coherent laser beam, which is known as Holography. The recorded transparent photographic plate is named Hologram. Holography Principle Holography is the process of recording a wave on square law medium and later releasing the same. A wave can carry information in the