In an optical recording medium drive apparatus, an optical recording medium is illuminated with a laser beam emitted from a head via an objected leans, and the head detects light reflected from the optical recording medium being illuminated with the laser beam. A signal generator generates a reflected light signal in accordance with the reflected light detected by the head. A controller drives the objective lens via a focusing unit, and detects peaks in the reflected light signal obtained when the objective lens is driven in a focusing direction. The controller determines whether the optical recording medium is of a single layer type or a multiple layer type by determining whether a pattern of the detected peaks is similar to one of patterns which can occur if the optical recording medium is of the single layer type.

 
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