Optical information-reproducing apparatus using separately located photodetector assemblies.

摘要

A light beam emitted from a light source (1) is split into three light beams by diffracting the light beam by means of a diffraction grating (2). The three light beams are reflected by the first side (31) of a plane-parallel plate (3). The reflected light beams are projected onto an optical disk (100). The three signal light beams are reflected by the optical disk (100) and returned to the plane-parallel plate (3). The plane-parallel plate (3) transmits part of the signal light beams to a first photodetector (5) and reflects part of the signal light beams from the second side (32) and transmits the reflected light beams to a second photodetector (6). The first photodetector (5) receives the central light beam. The second photodetector (6) receives the side light beams. The overall size of the apparatus can thereby be reduced. <IMAGE>