A beam-deflection probe as a method for optodynamic measurements of cavitation bubble oscillations

High-intensity light from a laser pulse can produce laser-induced breakdown in a liquid followed by a shock wave and the growth of a cavitation bubble. When the bubble reaches its maximum radius, the pressure of the surrounding liquid causes it to collapse; this results in bubble oscillations. The cavitation bubble's oscillations and the corresponding shock waves were measured from the deflections of a laser beam. These deflections were detected using a fast quadrant photodiode, built into the optical probe. The precise relative-positioning system and the small diameter of the beam's waist made it possible to detect and analyse the signals from the shock wave and the cavitation bubble. Here, we have demonstrated that a method based on a beam-deflection probe can be used to measure the fast phenomena that follow immediately after laser-induced breakdown as well as the whole dynamics of the bubble oscillations, which corresponds to a three-orders-of-magnitude larger time scale.