An optoacoustic probe including an ultrasound transducer array, an acoustic lens and a light path separated from the transducer array by an isolator to mitigate light energy from the light path from reaching the transducer array. The isolator being formed from a mixture including a flexible carrier, a coloring and between 10% and 80% by volume micro-bubbles. The isolator mixture being adapted to both absorb light energy and the optoacoustic response to light energy. In an embodiment, an optoacoustic probe also comprises an optical window and/or a diffuser, and the isolator also separating the transducer array from these components.
