A highly flexible pulsed photoacoustic setup based on a tunable laser source and external modulation

In this paper performance enhancement in PA measurements through optical pulse shaping is explored and demonstrated. A recently introduced setup, which is based on a CW tunable laser source operating in the optical communications band (1510-1620nm) and an electro-optic modulator, offers exceptional flexibility in controlling the temporal and spectral characteristics of the excitation waveform. Despite its being remarkably simple to construct and to operate, the unique optical configuration of this setup opens the possibility for a range of attractive applications which cannot be implemented by the commonly used pulsed lasers: responsivity and sensitivity optimization through pulse-shaping, enhancement of spatial resolution through pulse compression and simple implementation of high-resolution quantitative spectroscopy.