| 摘要 |
PROBLEM TO BE SOLVED: To greatly reduce the effect of the disturbance that rises in detecting a focusing error signal by an astigmatic detection method in reproducing a DVD-RAM, etc., also to greatly reduce the effect of offset involved in the displacement of an objective lens, which rises in detecting a tracking error signal by a push-pull method and further to realize a versatile optical disk apparatus which responds even to the reproduction of a variety of high density optical disks, such as DVD-RAM and DVD-ROM disks, as well as conventional disks, such as CD, CD-ROM and CD-R disks by using a simple optical head. SOLUTION: This versatile optical disk apparatus obtains satisfactory focusing error signal and tracking error signal by being provided with an optical detector divided into twelve parts with a prescribed configuration, which irradiates a specified position of an optical disk with three optical beams separated by a diffraction grating, and can reproduce a signal from a plurality of optical disks with different recording density and disk configuration by using the simple optical head. |
