System for controlling the wavelength and colinearity of multiplexed laser beams
US4847479A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1988 |
| Grant date | Jul 11, 1989 |
| Priority date | — |
| Expiry date | Jun 6, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/4087
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Apparatus and a related method for control of the colinearity of multiple laser output beams in a wavelength-multiplexed optical communications system. Multiple lasers of different wavelengths formed into a single composite beam by means of a diffraction grating and other optical components are subject to loss in colinearity due to wavelength drift and mechanical alignment drift. The apparatus of one disclosed embodiment of the invention includes an alignment detector for the output beam and a set of tracer modulation detectors responsive to tracer modulation signals impressed on the individual laser beams. Misalignment detected in any one or more of the laser beams contained in the output beam is corrected by temperature control of the appropriate lasers. In another disclosed embodiment of the invention, misalignment is detected by partially reflecting the output beams back through the diffraction grating and other optical components to the lasers, but at angles slightly divergent from the common plane of the lasers. Position detectors located adjacent to the lasers, but not in the same plane, receive the return beams and are coupled to temperature control devices to adjust the in…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.