Abstract:

It is often found that there are non-circular quadratic fringes such as ellipse and hyperbola appeared

in the experimental adjustment of Michelson interferometer. Aiming at this phenomena，this paper deduces the mathematical equation of the interference fringe based on the principle of non-local interference under the condition of point light source. On this basis，the shape of interference fringes under different conditions is analyzed. It is found that there are five kinds of line shapes of interference fringes can be acquired，they are circular，elliptic，parabolic，hyperbolic and straight. Based on the theoretical results，numerical simulation and experimental verification are carried out，and the numerical simulation results are in good agreement with the experimental results.

Key words: Michelson interferometer, non - localized interference, curve equation, the shape of interference fringes