Surface profilometry by digital holography

• Published in: 2017 22nd IEEE International Conference on Emerging Technologies and Factory Automation (ETFA) pp. 1 - 5
• Main Authors: Psota, Pavel, Ledl, Vit, Kavan, Frantisek, Mokry, Pavel, Matousek, Ondrej
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.09.2017
• Subjects: absolute measurement; digital holography; frequency scanning; Holographic optical components; Holography; Optical surface waves; Surface profilometry; Surface topography; Surface waves; Temperature measurement; Wavelength measurement
• DOI: 10.1109/ETFA.2017.8247748

This paper presents newly developed method for measurement of surface topography based on frequency scanning digital holography. Digital holography allows for direct computation of the phase field of the wavefront scattered by an object. A tuning of the light source optical frequency results in linear phase variation with respect to the optical frequency. Slope of the linear function in every single pixel corresponds to absolute measurement of optical path difference and thus topography map of the surface can be retrieved. Principle of this contactless method is introduced and experimentally verified. The method can be used for measurement of complex geometries of common manufacturing parts as well as for topography measurement of complex composite structures, and active acoustic metasurfaces.