Method and apparatus for controlling the wavelength of a laser
US6222861A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1998 |
| Grant date | Apr 24, 2001 |
| Priority date | — |
| Expiry date | Sep 3, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/572
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for controlling the wavelength of a laser. Initially, the wavelength of the laser is coarsely tuned to within a predetermined window around a specified wavelength. After coarse adjustment, a wavelength control loop is activated to finely tune and lock the laser wavelength. In an embodiment, the control loop dithers the wavelength of the optical carrier signal from the laser. The optical carrier signal is then modulated (i.e., with data) in the normal manner. A portion of the modulated optical signal is filtered and detected. The amplitude and phase of the detected signal, which comprises the error signal, is processed and averaged. The averaged signal is then summed with a dither signal to provide a composite signal. A control signal corresponding to the composite signal is then generated and used to adjust the laser wavelength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.