DVD tracking servo control system for high speed reading eccentric disc

Abstract

A DVD tracking servo control system for high-speed reading of eccentric discs in the field of electronic information technology, wherein: the circuit of the band-pass filter module is mainly composed of a signal processing circuit and an inverter circuit, and the detection conversion module converts the laser reader's The optical signal is converted into an electrical signal, and then compared with the given value of the system to generate an approximately linear tracking error signal. The intelligent decision-making module identifies whether the disc has eccentricity after processing the tracking error signal. If there is eccentricity, it uses The band-pass filter module compensates and corrects the tracking error signal distorted due to eccentricity, and then outputs it to the tracking servo system through the general control module; otherwise, it directly enters the general control module and then outputs it to the tracking servo system. The invention can read eccentric DVD discs at high speed, greatly improves the anti-Run-Out interference capability of the DVD system and the performance and success rate of reading eccentric discs, has good system stability, simple form, and few parameters, and is easy to be online debugging.

Description

technical field [0001] The present invention relates to a control system in the field of electronic information technology, more specifically, to a tracking servo control system for high-speed reading of eccentric DVD discs. Background technique [0002] DVD disc drive tracking servo control mechanism is mainly composed of two parts: a coarse adjustment actuator and a fine adjustment actuator. Its equivalent physical model can be regarded as a double-car structure. There are complex coupling relationships. Among them, the cart corresponds to the coarse adjustment actuator, which is generally a DC brushless motor, which is mainly used for fast and long-distance tracking. It has a large moving range, but the bandwidth is relatively small, and the corresponding speed is relatively slow. The trolley corresponds to the fine-tuning actuator, which is a voice coil motor and carries the laser reader OPU (optical pick-up). Its main function is short-distance tracking and tracking. T...

AI Technical Summary

Problems solved by technology

Therefore, for an eccentric disc with a maximum amplitude of 50 μm, the optical head deflection of the laser reader cannot exceed 0.022 μm, that is, the ratio of tracking error to disc eccentricity cannot be greater than However, in order to meet this requirement, the standard characteristics of the ideal open-loop tracking servo determine that the rotation frequency of the disc cannot be greater than 23.1 Hz. For a speed higher than 23.1 Hz, the ratio of the tracking error to the eccentricity of the disc will be greater than K 0 , DVD tracking servo system will not meet the requirements

However, the speed of modern DVD has reached 48 times, and the speed of the spindle motor is 9600 rpm, about 160Hz, so the system cannot suppress such a high-frequency run-out disturbance signal, so it cannot read eccentric discs at high speed

[0004] After searching the literature of the prior art, it is found that the Chinese invention patent (application number 01110490.2) proposes an optical drive tracking servo system and method, which is used to control the optical read-write head to track the data track, including: Sensing device, control device, decision-making device and power device are only suitable for discs without eccentricity, and cannot solve the problem of sinusoidal cycle run-out (Run-Out) caused by disc eccentricity, let alone at a speed exceeding 23.1Hz Read eccentric DVD discs at high speed

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