To shorten the access time of optical disk equipment, a small optical head and an eccentricity correction circuit are required. This paper describes both a small optical head with a combined prism and a roof-shaped prism and an eccentricity correction method with synchronized sine wave. Two newly developed prisms make it possible to form the optical head by using only six optical parts. Eccentricity correction is performed by moving the actuator according to the synchronized sinusoidal correction signal. The amplitude and phase of the correction signal are matched to those of the track movement by a microcomputer. This eccentricity correction can reduce a 200 µm eccentricity to 10 µm , improve tracking ability, and shorten the random access time.