Optical disc apparatus and tracking error signal calculation circuit
US6134198A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 1997 |
| Grant date | Oct 17, 2000 |
| Priority date | — |
| Expiry date | Sep 8, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0901
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A tracking error signal calculation circuit has peak detection multiplication circuits which detect the peaks of the detection signals of left and right regions of a photodiode and multiply a coefficient for detecting the deviation of the beam light with respect to the track of the disc recording medium, subtraction circuits for removing an offset by subtracting these multiplication results from the detection signals, and a subtraction circuit which calculates a difference of the signal obtained by removing the offset (performs push-pull operation) and outputs a tracking error signal. The value of the coefficient can be changed by adding an alignment signal to the detection signal. In order to impart the frequency dependency to this coefficient, the alignment signal is added to the signal through a filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.