Silicon photonics-based laser Doppler vibrometer with an integrated phase modulator

In this paper, we report a silicon photonics-based laser Doppler vibrometer (LDV) aiming for a small-footprint LDV system. The LDV system was based on the arctangent approach of phase-generated carrier (PGC-Arctan) demodulation in a phase-modulating interferometer using an integrated silicon optical phase modulator (SiPh-PM). The LDV performances were experimentally evaluated using a discrete SiPh-PM, and an integrated core-chip module in which the main parts of the LDV system were monolithically integrated in a single silicon-photonics chip. They were compared with the results of a conventional heterodyned-based LDV configuration. The results demonstrated sufficient performance for LDV uses, indicating that the phase modulator-based, integrated silicon photonics LDV is usable in practical cases.