Tracking error signal generating device for preventing offset of the generated tracking error signal
US5258968A · kind A · utility
43Cited by
13References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 11, 1987 |
| Grant date | Nov 2, 1993 |
| Priority date | — |
| Expiry date | Dec 11, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/094
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A tracking error signal generating device using a four-segment detector in which signals from diagonally opposed elements are combined and the two so combined signals are phase compared. According to the invention, either before or during the combining, the output signals of the segments have high level components removed so as to reduce offsetting due to a non-uniform beam illuminating the detector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.