The use of optical waveform synthesis in photoacoustic measurements

In this paper we describe an optical setup which enables synthesis of the excitation waveform in photoacoustic (PA) measurements. The flexibility in generating an optical pulse with a predefined envelope can be used for enhancing the response of the setup to a particular measured medium. To demonstrate the features of the new setup the following experimental stages were performed. First, the step response of the system (setup and measured medium) was measured. Once the step response was known it was used to analytically predict PA signals of other pulses, with different pulse shapes. Next the predictions were compared with measured responses of the same pulses. Finally, pulse synthesis was used for achieving higher PA signal amplitude.