Method for measurement of surface profile change using a vernier scale in hologram interferometry

摘要: To measure the amount of surface profile change an object, a hologram is formed by recording on photographic media interference pattern between coherent light divided uniform, reproducible wave front and mutually reflected from object. The virtual image object as seen through developed media, properly illuminated, superimposed same with being inclined respect to predetermined amount. positions are adjusted result in formation fringes which spaced apart one another first scale length. Changes section will shifting those associated unchanged portion. fringe shift may be measured employing second having divisions differ scale, manner vernier such function change.