Alcatel

G&eacute;rard Orcel

Sophie Dubois

Bob J Overton

Eric Lacroix

Jean-Florent Campion

Sophie Vanpoulle

Jean-Fran&ccedil;ois Bourhis

Marie-Jos&eacute; Lina

Jean-Fran&ccedil;ois Regnier

A method of cooling an optical fiber during drawing through contact with at least one cooling fluid in at least one cooling area, wherein fast cooling, i.e. cooling that is faster than cooling in the surrounding air, from an initial temperature of the fiber to a temperature at the end of fast cooling of said fiber, is followed by slow cooling, i.e. cooling slower than cooling in the surrounding air, from a temperature of said fiber at the start of slow cooling to a temperature of said fiber at the end of slow cooling.

Method of cooling an optical fiber while it is being drawn

A method of detecting a critical state of closing of a preform during a phase of closing of the preform following a phase of deposition of layers of material that reduce the radial size of an opening formed in the preform smaller in the radial direction comprises the steps of injecting a gas into the opening, measuring a pressure in a pipe element through which the injected gas flows and detecting the critical state of closing of the optical preform on the basis of a measured pressure.

Method of detecting when an optical preform MCVD tube is completely closed

Polyurethane acrylate or vinyl type polymeric material for coating optical fibers based on a fluorinated diol

An optical fiber preform comprising a core of radius R, and a sheath comprising cladding and outer sheath, wherein the outer sheath comprises an inner zone, and a peripheral zone made of silica doped with alumina and of thickness lying in the range 0.08 R to 2.2 R, and the proportion by weight of alumina in the peripheral zone is such that the equivalent concentration of alumina in the outer sheath as a whole lies in the range 100 ppm to 1000 ppm by weight of aluminum relative to silica. A method of manufacturing said preform, and an associated optical fiber.

Preform including a barrier layer preventing hydrogen from diffusing into optical fiber manufactured from said perform, and a method of preparing such a preform

Growing community of inventors

Maison Laffitte, France

Gérard Orcel

Growing community of inventors

Maison Laffitte, France

G&eacute;rard Orcel

Gérard Orcel