Probing micro-plastic items with coherent light enables their identification through digital holography

Detection of micro-plastics in water samples is a highly pursued goal to map the distribution and abundance of these pollutants. Here we investigate the possibility to probe microplastics with coherent light and to image them by digital holography microscopy. From the recorded hologram, we access the phase-contrast map of the object. We show that this map can be used as a distinctive fingerprint to identify microplastics in water.