CD focus error gain values determine method

Abstract

This invention relates to disc slice focus error gains value determining method with one special disc slice composed of roller scalar, one special operation area and one scalar description area, which comprises the following steps: putting the disc into disc record machine with roller facing one optical read head in the record; the read head detects signals on description area to get one first focus error gains value and one first side beam integral signal for signal detecting on special operations to get one second side beam integral signal; comparing the first and second side beams signal intensity to get one proportion relationship.

Description

technical field [0001] The invention relates to a method for determining the focus error gain value of an optical disc, especially a control process for setting the focus of a special optical disc that can be used as a label surface for an optical disc recorder. Background technique [0002] For users who often use a CD recorder for data backup, after backing up data on a rewritable CD, they often feel that the monotonous and non-special pattern on the back of the CD cannot represent the data that has been burned and backed up. The common practice is to use a marker pen or a special pen for optical discs to directly mark the name of the backed up data on the back, or to use some printers that can be used to print the label on the back of the optical disc to print the pattern or text on the label paper. However, it may be difficult to operate because the weight distribution of the paper is uneven, or the paper is not firmly pasted on the back of the disc, falling off or jammi...

AI Technical Summary

Problems solved by technology

As shown in the figure, it can be known that the focus S-curve formed by the voltage waveform of the general focus error signal will present a very complete and regular waveform change diagram, so the optical disc recorder can obtain the correct and reasonable FE gain value and Perform correct focus control, however, when the focus S-curve generated comes from the above-mentioned low-reflection area of ​​the signal, the focus S-curve will be affected; Schematic diagram of the change of the focus S-curve formed by the focus error signal in the control process of the interpretation in the operating area 11

As can be seen from the figure and the above content, due to the existence of the signal low reflection area in the characteristic operating area 11, the obtained focus S-curve cannot present a very complete and regular waveform, so it is impossible to obtain a correct and accurate waveform. A reasonable FE gain value will cause the obtained FE gain value to be either too large or too small, which will easily cause a focus server (Focus Servo) in the CD recorder to fail to focus correctly and lose focus

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