Multiwavelength Digital Holography

doi:10.1117/3.2190844.ch7

Book: Analog and Digital Holography with MATLAB

Author(s): Rola Aylo, Georges T. Nehmetallah, Logan Williams

Published: 2015

https://doi.org/10.1117/3.2190844.ch7

Author Affiliations +

Abstract

Another application of HI is the generation of a fringe pattern corresponding to contours of constant elevation with respect to a reference plane (see Fig. 7.1). Such contour fringes can be used to determine the shape of a 3D object. Holographic contour interferograms can be generated by the two-illumination-point method (discussed in Section 5.2); the two-refractive-index technique, which is generally not practical because the refractive index of the medium wherein the object is located must be changed; and the two-wavelength method, which is discussed in this chapter.