All-optical platform for ultrasound transmission matrix measurement using optoacoustic generation and silicon photonics detection

We present an all-optical ultrasound system that combines wideband (>50 MHz) optoacoustic signal generation with omnidirectional, high-fidelity detection using a silicon-photonics acoustic detector (SPADE) for transmission matrix measurements. Structured ultrasound sources are generated by projecting spatially coded laser pulses via a digital micromirror device, while a single-element SPADE is scanned to form a virtual receiver array. Acoustic responses for each transmission–receiver pair are reconstructed using an inverse S-matrix, enhancing the signal-to-noise ratio. Performance was validated by imaging a 400 μm scatterer, showing strong agreement with simulations and outperforming a conventional piezoelectric transducer. The system enables high-resolution, quantitative imaging with aberration correction.