Chinese Optics Letters, Volume. 22, Issue 3, (2024)
Non-contact ultrasound sensing based on Mach-Zehnder homodyne interferometer for photoacoustic imaging [Early Posting]
We present a novel non-contact ultrasound (US) and photoacoustic imaging (PAI) system, overcoming limitations of traditional coupling media. Using a long coherent length laser, we employ a homodyne free-space Mach-Zehnder setup with zero-crossing triggering, achieving a noise equivalent pressure of 703 Pa at 5 MHz and a -6 dB bandwidth of 1-8.54 MHz. We address phase uncertainty inherent to the homodyne method. Scanning the non-contact ultrasound probe enables photoacoustic computed tomography (PACT). Phantom studies demonstrate imaging performance and system stability, underscoring the potential of our system for non-contact US sensing and PAI.
Manuscript Accepted: Nov. 10, 2023
Posted: Nov. 20, 2023