An Improved Large-Field Microscopic Speckle Interferometry System for Dynamic Displacement Measurement of MEMS

Abstract

The traditional microscopic speckle interferometer has limited applications in engineering due to its small field of view. In this paper, we propose a large-field microscopic speckle interferometer which embeds two doublet lens groups in the improved Mach–Zehnder optical path structure to expand its field of view. At the same time, the new system can reduce the coherent noise of reflected light in the optical path. We use this new system to measure the dynamic displacement process of the entire surface of the microchips. The experimental results show that our improved measurement system can achieve large-field, real-time and high-precision dynamic measurement of micro-electromechanical systems (MEMS).

Special Issue “Optical Fiber Interferometric Sensors: New Production Methodologies and Novel Applications”

“…They proposed a large-field microscopic speckle interferometer, based on two embedded doublet lens groups for the realization of an improved optical Mach-Zehnder system. With the proposed solution, the authors can expand the field of view, while reducing the coherent noise of the reflected signal, achieving a high precision and real time dynamic measurement of MEMS [1].…”

Synchronous measurement of surface deformation and gradient distribution in microstructures

“…Thus this type of measurement method is not suitable for the precise measurement of sensitive materials. Noncontact measurement mostly adopts optical and various microscope methods, such as optical probe, 7 microscopic interference, 8 and scanning acoustic microscopy 9 . Optical measurement technology with interference technology has the advantages of noncontact process, quick measurement, and high precision.…”