Charge Coupled Devices

CCDs have been “workhorse” detectors providing imaging photon counting with spectroscopy at the prime focus of X-ray telescopes for almost three decades, and in the case of the “great observatories” of XMM-Newton and Chandra have been returning science data for over 20 years. The CCD optimized for X-ray detection is often different from its variant working in the visible light region. This chapter describes the key performance parameters of relevance to the X-ray CCDs, including instrument considerations and examples, together with performance over time. While design considerations such as noise and QE are described, long-term operational problems arising from radiation damage and contamination are also considered.