Fast phase-shifting technique for 3-D surface micro-topography measurement.

• Fast phase shift technique for rapid inspection of samples is presented. • Results were compared with those extracted by three-step phase shift. • In term of accuracy, the obtained results are not bad. • This technique can be applied for fast inspection of optoelectronic samples. This paper presents a two-step phase-shifting interferometry technique for fast inspection of uniformity of optoelectronic samples. The in-line configuration was applied to make full use of the space-bandwidth product (SBP) of the camera and hence can resolve finer spatial details of the sample. Two-step phase-shifting (TSPS) algorithm was used to reconstruct the object with only two in-line interferograms generated when a quarter wave plate (QWP) is placed in the light path of one arm of the Mach-Zehnder interferometer. Experimental results show that the extracted phases calculated by the TSPS technique match with the phases extracted by the three-step phase-shifting (THSPS) technique. [ABSTRACT FROM AUTHOR]