PURPOSE: To synchronize with the light emitting control applied to plural laser light sources and to separate plural pieces of information included in a photodetecting sensor output by applying successively the light emitting control to the plural laser light sources and including plural pieces of information recorded to recording media into the output of a common photodetecting sensor with a time division.
CONSTITUTION: A light emitting control means 20 supplies a synchronizing signal 21 to a driving means 5 of a semiconductor laser array 2, a reproducing signal separating means 18 and an error signal generating means 19. The driving means 5, based upon the synchronizing signal 21, semiconductor lasers 2a and 2b alternately emits light and the separating means 18 and the error signal generating means 19, are operated based upon the synchronizing signal 21. Respective laser beams 3 and 4, based upon respective pieces of information recorded at the disk, is applied with intensity modulation and reflected, then made incident on a half mirror 11, divided into two, one side is supplied to a photodetecting sensor 15, the other side is supplied through a converging lens 12 and a cylindrical lens 13 to the second half mirror and divided into two photodetecting sensors 16 and 17. In an output (a) of the photodetecting sensor 17 for reproduction, two types of information are included and the reproducing signal separating means 18 separates two pieces (c) and (d) of information based upon a synchronizing signal (b).
MURATA SEIJI
MINECHIKA SHIGEKAZU
WASHIMI SATOSHI
