Method of making polarization retaining fiber
US5152818A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1990 |
| Grant date | Oct 6, 1992 |
| Priority date | — |
| Expiry date | Nov 9, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B2207/40
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Disclosed is a method of making a polarization retaining single-mode optical fiber. Longitudinal grooves are formed on opposite sides of a cylindrically-shaped core perform having a glass core surrounded by cladding glass. The core preform is inserted into a glass tube, the tube is shrunk onto the core preform, and the interface between the core preform and the tube is fused to form a solid preform having longitudinal apertures on opposite sides of the core. An etchant gas is flowed through the apertures to enlarge the apertures into holes having a substantially round cross-section. Inserted into each aperture is a stress rod formed of glass having a coefficient of expansion different from that of the cladding glass. The resultant draw blank is drawn to form a single-mode optical fiber having a core that is subjected to a stress-induced birefringence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.