ABSTRACT
Since the introduction of the compact disc in the early 1980s, optical storage has become a well-known, widely spread, and generally accepted technique for storing and distributing data. The disks can handle a huge amount of information, they are inherently cheap, and, maybe most importantly, the mass replication of the polycarbonate disks allows content providers (audio, video, and software manufacturers) to distribute their product at a low cost.Although optical recording technology has evolved to a high degree of maturity, the demand for ever-increasing data rates and storage capacities constantly challenges R&D to come up with new and better solutions. In this entry we present an overview of this mature technology, and discuss the optics and mechanics involved in constructing optical pick-up heads.
