Ultrasonic imaging system and method for controlling synchronization

A method for controlling synchronization, the method comprising:

• a step of causing a probe provided to receive a photoacoustic wave to perform a reception operation in a state in which an insertion member having a light absorption element converting a light pulse from a light source into the photoacoustic wave is inserted into a living body;
• a step of determining detection or non-detection of the photoacoustic wave based on first reception information generated by the reception operation of the probe;
• a step of calculating a synchronization deviation between a light pulse cycle in the light source and a reception cycle in the probe as an actual measurement value based on second reception information generated by the reception operation of the probe, in a case where the detection of the photoacoustic wave is determined;
• a step of estimating the synchronization deviation as an estimation value based on a synchronization deviation history including a plurality of actual measurement values sequentially calculated, in a case where the non-detection of the photoacoustic wave is determined;
• and
• a step of changing at least one cycle of the light pulse cycle or the reception cycle based on the actual measurement value in a case where the detection of the photoacoustic wave is determined or changing the at least one cycle based on the estimation value in a case where the non-detection of the photoacoustic wave is determined.