Achieving wide-aperture insonification with high sensitivity typically requires a channel count incompatible with practical systems; sparse array configurations provide an effective tradeoff by enabling spatial aperture decimation while preserving transmit–receive performance. A second limitation arises from time of flight with pulse-echo (PE) acquisition modes. Because acoustic propagation speed is fixed, PE inherently restricts frame rate and exhibits extremely low sensing duty cycles, limiting its ability to capture short-lived or high-velocity events. On the other hand, long coded excitations can increase energy deposition. They also generate transmit–receive overlap and blind zones in single-aperture implementations.

We recently introduced Continuous Emission Ultrasound Imaging (CEUI) that addresses these constraints by replacing temporally discrete pulses with continuous, spatially and temporally encoded waveforms. Leveraging sparse arrays to physically decouple transmit and receive apertures, CEUI enables uninterrupted insonification and continuous data acquisition. This architecture removes the round-trip waiting time, theoretically allowing unbounded frame rates. This talk introduces CEUI as the convergence of sparse array design, compressed acquisitions and computational methods for image reconstruction. We will outline its core principles, the methods designed to decode the received raw signals and beamform M- and B-mode images, and demonstrate its ability to reach unprecedented imaging speeds—exceeding 100,000 frames per second—through simulations and early experimental results.