Optical recording/reproducing apparatus including a semiconductor laser having a plurality of radiative portions having different physical characteristics

摘要

An optical recording/reproducing apparatus comprises a semiconductor laser having a plurality of radiative portions formed at different heights on a same substrate and a spot forming system for arranging beams from the plurality of radiative portions in the semiconductor laser to form a plurality of light spots on an information recording medium for effecting information record and reproduction. In the apparatus, the spot forming system concurrently forms a first recording light spot and a first reproducing light spot on a first information track on the information recording medium and concurrently forms a second recording light spot and a second reproducing light spot on a second information track different from the first information track on the information recording medium.