METHOD FOR SETTING UP FOCUS SERVO BIAS IN OPTICAL DISK DEVICE

摘要

PURPOSE: A method for setting up a focus servo bias in an optical disk device is provided to promptly and stably operate an optical disk drive servo system by obtaining a focus error level with a focus bias adjustment value. CONSTITUTION: A focus lens maintains a down state(301). If a disk is inserted, the focus lens starts going up by a driving signal from an optical pickup drive IC(302). Signal detected by an optical pickup are output as focus error and RF level signals, and the focus error and RF level signals are converted into digital values to be transmitted to a micro controller(303). The micro controller stores the digital values in a memory until the rising of the focus lens is terminated(304). The micro controller confirms the rising of the focus lens by detecting the focus error and RF level signals output from the A/D(Analog to Digital) converter(305-306). The micro controller calculates the maximum position value among the focus error and RF(Radio Frequency) level signals stored in the memory(307). The micro controller obtains a focus error level value at the calculated maximum position value(308). The micro controller provides the focus error level value, that is a focus bias adjustment value to a servo signal processing unit for completing adjustment of a focus servo bias(309).