Trigger Mechanism Using Interferometer for Displacement Measurement Device by Phase-Shifting Digital Holography

Abstract

Phase-shifting digital holography must capture several holograms. A shift mechanism is also essential. The conventional method utilizes a shift mechanism with feedback control of a piezoelectric device (PZT). In my laboratory, we developed a phase-shifting mechanism using a small, inexpensive PZT without feedback control. This phase-shifting mechanism is called as an interferometer trigger mechanism. In this study, the displacement distribution of a cantilever is measured using a shift mechanism with feedback control of a PZT, and a shift mechanism with an interferometer trigger. A comparison of the results indicates the effectiveness of the interferometer trigger mechanism for the measurement of displacement distribution.