Optical imaging modalities are commonly characterized by rapid acquisition rates, enabling real-time feedback. Photoacoustic Remote Sensing (PARS) microscopy takes advantage of intensity reflectivity modulations induced through large photoacoustic initial pressures to provide optical absorption imaging contrast. The PARS signals are characterized by short time-domain behavior independent of time-gated effects such as acoustic propagation to a detector. Here, improved imaging rates are demonstrated. This is accomplished by introducing an analog peak detection circuit, which reduces data bandwidth requirements, and by employing a high repetition rate fiber laser. These additions enable voxel scan rates in the megahertz range. High quality real-time captures, orders of magnitude faster than previous PARS systems, are presented.
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