Paper
14 August 2006 Surface shape measurement by phase-shifting digital holography with dual wavelengths
Author Affiliations +
Abstract
A simple method for surface contouring by phase-shifting digital holography is reported. Diffusely reflected light from a coherently illuminated object is recorded by a CCD with coherent in-line superposition of a reference beam subject to phase-shifting. From three phase-shifted in-line holograms the complex amplitude of the object wave at the CCD plane is derived to reconstruct phase distributions before and after wavelength shift that is provided by a mode-hopping induced by a change of injection current of a laser diode. The difference of the reconstructed phases corresponding to each of the wavelengths is proportional to surface height from the reference plane that is normal to the incident beam. This setup permitting normal incidence introduces neither the carrier component corresponding to oblique reference plane nor the shadowing effect that arise in the fringe projection and the dual incident angle methods requiring oblique illumination. In experiments plane surfaces tilted by various angles are first measured to evaluate accuracy. Then a spherical surface and a miniature valve are employed. The results are compared with one-dimensional simulations using random number model of surface roughness to exhibit good agreement.
© (2006) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Ichirou Yamaguchi, Takashi Ida, and Masayuki Yokota "Surface shape measurement by phase-shifting digital holography with dual wavelengths", Proc. SPIE 6292, Interferometry XIII: Techniques and Analysis, 62920V (14 August 2006); https://doi.org/10.1117/12.681970
Lens.org Logo
CITATIONS
Cited by 2 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Charge-coupled devices

Phase shifts

Digital holography

3D image reconstruction

Holograms

3D displays

Semiconductor lasers

Back to Top