A flat type optical head for focusing a light beam onto an optical memory.

摘要

In a flat type optical head for focusing a light beam, a semiconductor laser (9) is mounted on a mount (8) which is fixed on a base (5). A Fresnel lens structure is formed on optical detecting layer (12) which is formed on the base (5). A laser beam generated from the semiconductor layer (9) is incident on a converging layer (6) of the Fresnel lens structure and is converged on an optical disk by the converging layer (6). The laser beam reflected from the optical disk is returned to the converging layer (6). A part of the laser beam passes through the converging layer (6) and is detected by the optical detecting layer (12).