Method and apparatus for expanding the dynamic range of optical amplifiers
US6721089B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2001 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Nov 4, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/094003
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The dynamic range of an optical amplifier is extended by the addition of a power control circuit. A switch is interposed between a current source and an optical pump supplying pumping light to the gain medium of the optical amplifier. A modulated signal such as a pulse-width modulated signal is used to actuate the switch and control a relative duration of the “on” and “off” periods of the electrical current supplied to the optical pump. Gain latency in the optical amplifier permits a substantially continuous signal to be output from the optical amplifier in response to the switched electrical current supply to the optical pump. A controller may used a feedback signal from the optical pump or from a power monitoring device to control the modulator and, thereby, the switch. A target pump power level, target gain or target amplified signal power level may also be applied in a feedback control loop that controls the modulator and switch. The invention also takes the form of a method that may be used to control a conventional optical amplifier in order to expand the dynamic range, particularly in the low power region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.