Apparatus and method for measuring polarization-dependent loss using repeated high speed polarization scrambling
US6657709B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2002 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Nov 15, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/105
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed is an apparatus and method for measuring a changing amount of insertion loss of an optical device depending on a polarization state of an incident light, i.e., a polarization-dependent loss. An incident light that is periodically subject to all polarization states passes through a testing optical device by a polarization scrambler including a piezoelectric element type optical fiber birefringence modulator, and an optical detector measures intensity of the passing light, in which the measured intensity values are averaged for birefringence modulation having a constant period, and then the polarization-dependent loss is computed from a ratio of maximum power to minimum power for the period. Use of the birefringence modulator shortens measuring time, and decreases an affect of external disturbance to the incident light that is incident into the testing optical component or occurrence probability of the external disturbance, so that the polarization-dependent loss can be precisely measured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.