E-Mail IMAGE: Simultaneous multicontrast OR-PAM of hemoglobin concentration, oxygen saturation, blood flow speed, and lymphatic concentration; doi 10.1117/1.AP.3.1.016002 view more Credit: Wang, et al. Optical-resolution photoacoustic microscopy (OR-PAM), a new hybrid imaging technique, allows us to listen to the sound of light and see the color of biological tissue itself. It can be used for live, multicontrast functional imaging, but the limited wavelength choice of most commercial lasers and the limitations of the existing scanning methods have meant that OR-PAM can obtain only one or two different types of contrast in a single scan. These limitations have made multicontrast functional imaging time-consuming, and it's been difficult to capture the dynamic changes of functional information in biological tissues.