ABSTRACT
This chapter describes important aspects of optical disk recording and readout technologies, with a brief historical introduction and references for further study. Development of rewritable optical disk systems accelerated in the 1980s as the performance of reversible media progressed. Optical disks are used in various applications, including audio, computer memory devices, picture files, document files, and video files. Four types of standardized players are available for read-only optical disks: video disk, audio disk, data file disk, and digital versatile disk. The optical pick-up generally consists of an optical base forming the optics assembly and an actuator for allowing the objective lens to follow the disk plane and tracking groove. The optical base has a three-point support structure that enables a two-dimensional adjustment of the tilt angle of the optical pick-up. The laser beam in an optical disk system is focused on the disk surface while the disk rotates at a high speed.
