Contouring by electronic speckle pattern interferometry employing divergent dual beam illumination

Abstract

For contouring of large object surfaces by means of electronic speckle pattern interferometry divergent illuminations were used. A method to shift dual illumination beams was employed to obtain contour fringes. The relationship between the fringes and object depth does not have the same form as in the case of collimated illuminations. It shows that the original measurement data can be corrected. Theoretical analysis and experimental results are presented which are in agreement with each other.