Invention Grant
US07660223B2 Disc device 失效
光盘设备

Disc device
Abstract:
A disc device includes a lens that focuses a laser light on an optical disc surface, a focus drive unit that drives the lens in a focusing direction, a focus control unit that controls to focus the laser light on the optical disc surface, a focus displacement detecting unit that detects a displaced amount in the focusing direction, a differentiation unit that differentiates a focus displacement detected signal, and a unit that inverts a sign of a differentiated signal, thereby, the disc device is driven intermittently to restrain a motion of an objective lens in a focusing direction and avoid colliding the objective lens with the optical disc surface.
Public/Granted literature
Information query
Patent Agency Ranking
0/0