摘要 |
According to one embodiment, an optical disc distinguishing method includes irradiating the loaded optical disc with a light beam having one of a first to third wavelengths, determining whether the loaded optical disc belongs to a first group consisting of a first to third optical discs or a second group consisting of two kinds of optical discs which do not correspond to the wavelength of the irradiated light beam, identifying the loaded optical disc as one of the first to third optical discs, irradiating the loaded optical disc with one of the two kinds of the light beams except for the light beam with which the loaded optical disc is irradiated in making the determination of the group when the loaded optical disc belongs to the second group, and identifying the loaded optical disc as one of the two kinds of the optical discs belonging to the second group.
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