Photonics Research Group Home
Ghent University Journals/Proceedings
About People Research Publications Education Services


Publication detail

Authors: Z. Yang, Y. Li, R. Baets
Title: Theoretical comparison of the signal-to-noise ratios of two types of vibrometers: Mach-Zehnder and Sagnac interferometers
Format: International Conference Presentation
Publication date: 3/2023
Journal/Conference/Book: Measuring by light
Location: Delft, Netherlands
Citations: Look up on Google Scholar
Download: Download this Publication (614KB) (614KB)


As well-recognized analytic techniques, non-destructive testing methods, including contact and non-contact, are widely used in evaluating and characterizing the properties of composite materials or other structures. The limitation of mobility of current implementations of contact methods narrows down the applications for flexible sensing from a distance. Meanwhile, non-contact testing methods can provide more flexibility than contact methods by measuring from a distance using coherent or incoherent light. Laser Doppler vibrometry (LDV) and Sagnac-based vibrometry are two competent interferometer-based non-contact testing methods. Here, we analyze and compare LDV and the Sagnac-based vibrometry from the perspective of their signal-to-noise ratio (SNR), considering the shot noise limitation. Then, we discuss possible approaches to reduce the overall noise level. We also discuss the possibility of minimizing a Sagnac-based non-destructive testing system on a photonic integrated chip since current fiber-based or free-space implementations are too bulky and expensive.

Related Research Topics

Back to publication list