Abstract: Method and apparatus for controlling high-speed rotation of optical disc, wherein the amount of disc vibration caused by disc rotation is calculated, and the disc rotation speed is increased based on the calculated amount of disc vibration in order to maximize the data transfer rate under a given amount of disc vibration. The apparatus of the present invention comprises a pickup for retrieving data recorded on an optical disc, a drive unit for driving motors, an R/F unit for equalizing and shaping signals reproduced from the optical disc, a servo unit for controlling the drive unit and detecting sync signals from the output signal of the R/F unit, a digital signal processing unit for retrieving original digital data from the output signal of the R/F unit, a timer for measuring the elapsed time between specific events, and a microprocessor for controlling the rotation speed of the optical disc based on the amount of elapsed time measured by the timer.

Abstract: The present invention relates to method and apparatus for controlling the slide of an optical pickup installed in the optical disk device so that deviation of an optical lens from an optical axis may be corrected. The corrective action is taken when the deviation reaches or is beyond a predetermined range. The predetermined is narrower than the maximum movable range of the optical lens. Also the corrective action is accomplished by adjusting either the DC component or the overall bandwidth of the servo gain loop depending on whether the rotational rate of an optical disk is high or low. Such method prevents or minimizes object lens from over-shifting or freely oscillating.

Abstract: A method and apparatus for focus control of an optical disk drive is disclosed. The method for focus control in accordance with the present invention changes focus servo loop characteristics when the optical pickup moves rapidly to perform track search operations so that the vibration of the objective lens is effectively attenuated, thereby allowing stable focus control and high-speed access capability.

Abstract: An apparatus and method for servo control in an optical disk driver. The amount of disk eccentricity is measured, and a compensation value corresponding to the measured disk eccentricity is calculated and stored. The stored compensation value is used in the track search mode so that a more stable and precise track search operation is achieved despite the disk eccentricity caused by imperfect disk manufacturing processes or disk clamping errors. Also, when a track jump is requested during a track-following operation, the jump start point is adjusted properly, thereby reducing the time needed to complete the track jump operation, as well as reducing track jump errors.

Abstract: Method and apparatus for controlling high-speed rotation of optical disc, wherein the amount of disc vibrations caused by the disc rotation is calculated and the disc rotation speed is increased based on the calculated amount of disc vibrations to maximize the data transfer rate under given disc vibrations. The apparatus of the present invention comprises a pickup for retrieving data recorded on an optical disc, a drive unit for driving motors, an R/F unit for equalizing and shaping signals reproduced from the optical disc, a servo unit for controlling the drive unit and detecting sync signals from the output signal of the R/F unit, a digital signal processing unit for retrieving original digital data from the output signal of the R/F unit, a timer for measuring the elapse time between specific events, and a microprocessor for controlling the rotation speed of the optical disc based on the elapse time measured by the timer.

Abstract: A method and apparatus for adjusting equalization characteristics of signals reproduced from an optical disk rotating at a constant angular velocity. The method according to the present invention includes measuring the linear velocity of an arbitrary track on a rotating optical disk medium and adjusting equalization characteristics of signals reproduced from the track based on the measured linear velocity. The method provides high fidelity data reproduction by allowing fine adjustment of equalization characteristics and general applicability, by exploiting signals recorded on the particular optical disk medium read.

Abstract: A method and apparatus for focus control of an optical disk drive is disclosed. The method for focus control in accordance with the present invention changes focus servo loop characteristics when the optical pickup moves rapidly to perform track search operations so that the vibration of the objective lens is effectively attenuated, thereby allowing stable focus control and high-speed access capability.