Science Fiction

As we know two coherent light source interference produce interference fringes which can shows various measurement factors change. The wavelength of light depends on the change in phase of signals or number of fringes with respect to change in distance between two sources. When half of wavelength distance is change than a fringe is pass or 2π phase change occur. So during change in distance we can calculate change in phase which is used for wavelength measurement.                       wavelength of light λ=(2Δd)/N where Δd is change in distance and N is change in number of fringes. Fringes detected by michleson interferometer by CCD.

The Michleson Interferometer is a two interferometer, when two coherent light beams interface with each other than maxima (bright fringe) occur where maxima of one beam superimpose with maxima of other beam and minima (dark fringe) occur where maxima of one beam superimpose with minima of other beam. For good quality of fringes we need coherent source so we use a beam splitter for split a beam into two parts. Beam travel at 90 degree with each other. Now use two mirrors for reflect back beams to beam splitter and superimpose with each other. A good quality michleson interferometer can be used for measurement operations like:- Wavelength of light  Refractive index of glass slits  Refractive index of air or gas Now the same principle used for detection of change in gravitational waves as discus in various posts.