A definition of CCD (Charge-coupled device)

A type of sensor used in digital cameras. CCD’s come in three main varieties: interline-transfer, frame transfer and full-frame (not to be confused with full-frame size sensors). Although the construction of each varies, in each case charge is transferred in a bucket-brigade fashion from one cell to the next, until it reaches the end of the row where it is converted into voltage. Interline transfer CCDs, which incorporate separate shielded sections to transfer charge to the end of each row, are most commonly used in digital compacts and SLRs, although today these have been largely replaced by CMOS types.