Photoacoustic tomography (PAT) detects ultrasound signals generated by the objects after absorbing illuminating photons. However, the widely used piezoelectric ultrasound transducers are generally not optically transparent, which would cause conflicts between the light illumination and the ultrasonic detection in PAT. We report a different acoustically penetrable optical reflector (APOR) concept to provide a solution to this conflict. We measured the properties of an APOR and experimentally tested its performance in a PAT system. The results demonstrated that the APOR successfully allowed the transducer to detector photoacoustic signals without affecting the light illumination. Moreover, the APOR concept can be readily implemented in various PAT systems.