Light signal detection circuit
US5910938A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 12, 1998 |
| Grant date | Jun 8, 1999 |
| Priority date | — |
| Expiry date | Feb 12, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10515
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An output current from the anode side of one photo-diode PD1 of two photo-diodes PD1, PD2 and an output current from the cathode side of the other photo-diode PD2 which serves as an in-phase signal with respect to the first mentioned output current are added in terms of current to convert an added current thus obtained into a voltage signal by a current/voltage converter 1. Thus, circuit such as summing amplifier, etc. can be omitted and this light signal detection circuit is only required to have one circuit/voltage converter 1. As a result, noise at the time of reproduction of a magneto-optical signal can be reduced while holding the circuit scale down to small size. Thus, S/N ratio of the reproduction signal is improved, thus, making it possible to improve, e.g., the error rate in the digital system to much degree. Accordingly, improvements, in reliability /information desity/transmission rate(speed) can be made.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.