Method of making a fiber having low polarization mode dispersion due to a permanent spin
US5298047A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1992 |
| Grant date | Mar 29, 1994 |
| Priority date | — |
| Expiry date | Aug 3, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B2205/06
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The presence of (typically unintended) birefringence in single mode optical fiber can severely limit the usefulness of the fiber for, e.g., high bit rate or analog optical fiber communication systems, due to the resulting polarization mode dispersion (PMD). It has now been discovered that PMD can be substantially reduced if, during drawing of the fiber, a torque is applied to the fiber such that a "spin" is impressed on the fiber. Desirably the torque is applied such that the spin impressed on the fiber does not have constant spatial frequency, e.g., has alternately clockwise and counterclockwise helicity. At least a portion of optical fiber according to the invention has a spin whose spatial frequency exceeds 4 spins/meter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.