Olympus Optical Company, Ltd.

Makie Morota

Shoji Yoshikawa

Yoshiaki Ikeda

Hiroo Okada

An optical information recording and/or reproducing apparatus is provided with a finely moving device. The movement of an optical device converging and radiating a light beam onto an optical information recording medium, is controlled to be able to finely move the position of a spot light radiated onto the recording medium. A coarsely moving device moves an optical head provided with the finely moving device and an optical system. A track crossing velocity monitoring device detects whether the track crossing velocity at which the spot light radiated onto the recording medium crosses the tracks of the recording medium is below a predetermined value. After a coarse access close to an objective track is made by the coarsely moving device, when the track crossing velocity is below the predetermined value, the clamping applied to the optical device at the time of the coarse access will be released.

Optical lens vibration control for optical information recording and/or

An optical pickup is arranged under an optical disk. Tracks of the disk are irradiated with a laser beam from the pickup. A beam reflected by a given track becomes incident on the pickup. A tracking error signal from the pickup is supplied to a lens moving actuator through a gain phase compensating circuit and a lens driving circuit, and an objective lens in the pickup is radially moved along disk. The tracking error signal is supplied to a voice coil motor through the phase compensating circuit. A carriage carrying the pickup thereon can be radially moved along the disk. When a tracking instruction is generated, the lens driving circuit drives the objective lens to start tracking. Meanwhile, the low-frequency components of the tracking error signal which are lower than the resonance frequency of the lens tracking circuit are amplified by the gain phase compensating circuit. When the tracking error signal is converged within a predetermined threshold range, the amplification of the low-frequency components of the tracking error signal is stopped. At the same time, the operation of the voice coil motor is started. Tracking is performed by both the objective lens and the carriage to achieve two-step servo tracking.

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Hino, Japan

Makie Morota