Patent ID: 6256275
Filing Date: 2001-07-03
Classification: G11B

Abstract:
A disc reproducing apparatus, comprising:an optical pickup for reading out information recorded on a disc as an RF signal and generating a tracking error signal; anda vibration detection means for detecting vibration generated, when the disc is driven, including:displacement amount detection means which detects, based on the RF signal and the tracking error signal, a first amount of displacement of the optical pickup and the disc produced in a direction of the disc surface when the disc is drive at a first speed and a second amount of displacement of the optical pickup and the disc produced in a direction of the disc surface when the disc is driven at a second speed which is faster than the first speed; andcalculation means which determines, as vibration caused by the mass eccentricity of the disc, a difference between the first amount of displacement and the second amount of displacement respectively detected by the displacement amount detection means.