Real-time 3D sensing and identification of microorganisms

Real time automated optical systems capable of visualizing and recognizing biological microorganisms in three dimensions using single exposure on-line (SEOL) digital holographic microscopy are discussed. SEOL holography reconstructs 3D images using signal processing and segmentation to separate the microorganisms. A charge-coupled device array is used to record the interference pattern caused by a microorganism in the Fresnel diffraction domain. A beam splitter divides the laser beam into object and reference waves. A digital hologram is then generated by the reference wave and the diffracted wave fronts of the specimen.