INFORMATION RECORDING AND REPRODUCING DEVICE AND DISK DISCRIMINATING METHOD FOR THE SAME

摘要

PROBLEM TO BE SOLVED: To realize recording of data to plural disks to be recorded with lasers of different wavelengths with one information recording and reproducing device and to provide a device which prevents erroneous recording and disk destruction particularly in discriminating the disks and discriminates the disk kinds with good accuracy. SOLUTION: A lens which is changed in numerical apertures according to the wavelengths is used for an objective lens for converging a laser beam to the disk. The kind of the disk is discriminated by the return light quantity from the disk and information is encoded by an encoder according to the kind of the disk. The recording is carried out by driving the laser meeting the kind of the disk by these signals. The discrimination of the kinds of the disks is performed by controlling the output power of the lasers in accordance with conditions.