source: © 2018 Optical Society of America
Optical detection of ultrasound is often characterized by limited dynamic range and lack of scalability. In this work, we present passive pulse interferometry (P-PI) as a solution to both these challenges.[Read More…]
Fig. 1. (a) A schematic drawing of the system used for pulse interferometry. (b) Active demodulation scheme consists of an unbalanced Mach-Zenhder interferometer (MZI) stabilized to quadrature using a wideband feedback circuit. PZ is piezoelectric fiber stretcher and FC is 50/50 fused fiber coupler. (c) Passive demodulation scheme consists of a dual-polarization unbalanced MZI, implementing a 90° optical hybrid. PBS is polarization beam splitter. (d) A schematic drawing of the system used for CW interrogation