| Title | Phase computing for automatic real-time applications |
| Author | Rigoberto Juarez-Salazar, Doctorate of Science Applied Physics, Meritorious Autonomous University of Puebla. |
| Adviser | Carlos I. Robledo Sanchez, and Curz Meneses Fabian. |
| Citation | Rigoberto Juarez-Salazar, “Phase computing for automatic real-time applications,” PhD Thesis, Faculty of Physical-Mathematical Sciences, Meritorious Autonomous University of Puebla, Puebla, Mexico, (July 2014). |
| Links | BibTeX PDF Thesis More Theses Español |
Abstract
Phase computing is one of the most important techniques in many scientific areas and engineering because of a wide variety of physical quantities that can be measured with high precision by noninvasive means. The phase-based optical measurement systems attain high accuracy, fast response (even in real-time), and they are low-cost. These features have been possible through recent technological advances such as laser diodes, liquid crystal displays, high-speed cameras, and high-performance computers. However, rapid technological development also demands improving the conventional phase demodulation methods.
This thesis is focused on phase demodulation for optical measurement using interferometric and non-interferometric setups. Fringe pattern phase demodulation methods are developed. The main specific contributions of this thesis are new phase-based measurement methods described as follows.
| 1. | Fringe pattern normalization by polynomial fitting using least squares. |
| 2. | Fourier fringe-normalized analysis. |
| 3. | Generalized phase-shifting algorithms for inhomogeneous phase shifts and spatio-temporal visibility variation. |
| 4. | Phase-unwrapping by rounding least squares approach. |
| 5. | Phase-shifting interferometry by lateral displacement of the light source. |
The first four contributions refer to phase computing, designed to be user-free, no specialized computer resources required, and easy to implement in other applications. The contribution 5 of the previous list concerns to a simple and inexpensive optical setup to interferometrical evaluations by phase-shifting where the required phase shifts are induced by coarse lateral displacement of the laser point source.
| Among the five contributions of this thesis, contribution 3 is the most outstanding. This contribution refers to a generalized phase-shifting algorithm able to handle inhomogeneous nonlinear phase shifts, large fringe contrast variations, and the capacity to work with a minimum of two fringe patterns. This contribution represents a novel method that, to the best of our knowledge, is the first to solve the phase computing problem in those generalized operation conditions. |
Keywords: Phase-shifting, Fourier fringe-normalized analysis, Phase-unwrapping, Fringe pattern normalization, Lateral displacement, Automatic real-time applications.
Publications
R. Juarez-Salazar et al., “Generalized phase-shifting algorithm for inhomogeneous phase shift and spatio-temporal fringe visibility variation,” Optics Express Vol. 22, Issue 4, pp. 4738-4750, 2014.
R. Juarez-Salazar et al., “Phase-unwrapping algorithm by a rounding-least-squares approach,” Optics Express Vol. 53, Issue 2, pp. 024102, 2014.
C. Robledo-Sanchez, R. Juarez-Salazar et al., “Phase-shifting interferometry based on the lateral displacement of the light source,” Optics Express Vol. 21, Issue 14, pp. 17228-17233, 2013.
J. Casco-Vasquez, R. Juarez-Salazar et al., “Fourier normalized-fringe analysis by zero-order spectrum suppression using a parameter estimation approach,” Optical Engineering Vol. 52, Issue 7, pp. 074109, 2013.
R. Juarez-Salazar et al., “Generalized phase-shifting interferometry by parameter estimation with the least squares method,” Optics and Lasers in Engineering Vol. 51, Issue 5, pp. 626-632, 2013.
R. Juarez-Salazar et al., “Automatic real-time generalized phase-shifting interferometry to process interferograms with spatio-temporal visibility,” Proc. SPIE, 8th Iberoamerican Optics Meeting, Portugal, pp. 878542, 2013.
R. Juarez-Salazar et al., “Straightforward filtering to phase demodulation by a Fourier normalized-fringe approach,” Proc. SPIE, 8th Iberoamerican Optics Meeting, Portugal, pp. 878543, 2013.
W. Guerrero-Sanchez, R. Juarez-Salazar, C. Meneses-Fabian, C. Robledo-Sanchez, “Fringe pattern simulation with an adaptive pendulum,” Proc. SPIE, Eighth Symposium Optics in Industry, Mexico, pp. 828713, 2011.