Disc filemark surface focusing control method

Abstract

A disc label surface focusing control method comprises the following steps: focusing a label surface by using a basic voltage; measuring and recording light summed signals; comparing to obtain the maximal light summed signal; reducing the maximal light summed signal by the light summed signal at each position to form a difference signal; gaining the difference signal to obtain a gain signal; adding the gain signal to the basic voltage to obtain an upper reference voltage; reducing the basic voltage by the gain signal to obtain a lower reference voltage; using the upper reference voltage and the lower reference voltage as the control focusing voltage; detecting and recording light summed signals; comparing to obtain the maximal light summed signal at each position; and forming an approach control focusing voltage curve by using a curve approximation method and using relative voltages so as to decide the optimal control focusing parameters.

Description

technical field [0001] The invention relates to an optical drive, in particular to a method for controlling focus when performing optical engraving labeling on the disc label surface in an optical drive with optical engraving function. Background technique [0002] Generally, optical drives with the function of Lightscribe apply a layer of paint on the label surface of the disc, and use the optical head to emit a laser beam to focus on the label surface of the disc. When the power of the laser beam is greater than a certain level, The label face changes to form a label pattern. Therefore, the optical head needs to keep the focus of the laser beam on the label surface of the rotating disk to obtain the label pattern. [0003] When focusing on the data surface of the disc in the existing optical drive, the electromagnetic force generated by the voltage is used to drive the optical head to move up and down, and control the light beam of the optical head to project on the disc....

AI Technical Summary

Problems solved by technology

[0006]However, when the optical head moves from the inner ring to the outer ring to write the label, due to factors such as disc tilt, deformation, swing or optical drive structure, the outer ring The change in the vertical direction is much larger than that of the inner ring, causing the optical head to lose focus to a certain degree. Even if the triangle wave voltage is adjusted, it cannot be improved, resulting in the optical sum signal not being able to reflect an appropriate error, making the parameters of the control voltage inaccurate, and affecting The clarity of the label, it is not even possible to engrave the label pattern

Therefore, there are still problems in the aforementioned label surface control focusing method, which need to be resolved.

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