Overview: The Continuous Particle Imaging and Classification System (CPICS) has produced unprecedented results in the in situ aquatic microscopy of plankton and particles in seawater, freshwater, and laboratory samples. Using darkfield illumination, the CPICS captures high-resolution color images, showing features as small as 1μm. Research has shown that color information is key to high-accuracy classification while also providing important physiological information such as pigmentation due to grazing on phytoplankton. Because of its open-flow approach to water sampling, the delicate structures of plankton and particles remain completely intact as do predator-prey interactions.
Technology: The CPICS employs a telecentric lens to produce a maximal depth of field, generating images with the same magnification throughout. The telecentricity removes any barrel distortion at the corner of the image that would disturb normal lenses. The high-resolution machine vision camera is coupled with the advanced lens system and an LED array for illumination purposes and operates at a variety of frame rates up to and including 19 frames per second. The camera also incorporates an Ethernet interface to allow simple connectivity using high-speed communications.