This lecture covers the different types of detectors used in microscopy, including the Eye, Photodiode, PMT, CCD, EMCCD, and CMOS cameras. It explains their structure, operation principles, and applications in digital imaging systems. The lecture also delves into the working mechanisms of Photo-diodes, Digital Imaging Systems, CCD architecture, and the EMCCD technology, emphasizing their significance in low-light imaging. Additionally, it discusses the advantages of CMOS technology over CCD in terms of speed, power efficiency, and cost-effectiveness.