Abstract:
Method of manufacturing a multi-component glass cylindrical part comprising the operations of providing a vertical cylindrical cavity lined with porous membranes whose inside dimensions are very slightly larger than those of the glass cylindrical part and in which can slide a cylindrical pedestal, providing a seed mass of the glass on the pedestal, heating the seed mass until it melts, injecting a gas continuously into the porous membranes to form and maintain a layer of gas between the porous membranes and the molten seed mass preventing any contact between the molten seed mass and the porous membranes, feeding the molten seed mass from the top of the cavity by continuously dispensing a powder made up of the components of the glass, varying the composition of the powder as the cylindrical part is formed, so that the glass cylindrical part has a composition that varies in the longitudinal direction, and lowering the pedestal as the cylindrical part is formed.
Abstract:
In a method of manufacturing a cylindrical part from glass, especially but not exclusively fluorinated glass, a vertical cylindrical cavity is lined with a porous material and its inside dimensions are a few tens of microns greater than those of the part. A cylindrical pedestal constituting a support for the part slides in the cavity. An initial seed mass constituted from the glass is provided on the pedestal. The seed mass is heated until it melts and a gas is injected permanently into the porous material in order to maintain between them and the molten seed mass a layer of gas a few tens of microns thick to prevent any contact. The molten seed mass is fed continuously from the top of the cavity with the powder constituents of the glass and the pedestal is lowered as the cylindrical part is formed from the seed mass.
Abstract:
The present invention concerns an optical guide (100) comprising an amplifier medium including: a core (10) in a main matrix of a transparent material, the main matrix containing particules (1, 2), each particule being formed of a submicronic matrix distinct from the main matrix and doped by an active metal element, an external guiding cladding (11) in contact with the core (10). The size of the particules (1, 2) is smaller than 20 nm. The present invention also concerns a method for producing this guide.
Abstract:
The invention provides a monomode optical fiber and a monomode preform (2) having a mother preform (22) housed in an outer sleeve tube (20). It is characterized in that it also includes an intermediate tube (21) between the mother preform (22) and the outer tube (20), the intermediate tube (21) possessing viscosity at fiber-drawing temperature which is less than the viscosity(ies) at fiber-drawing temperature of the mother preform (22) and of the outer tube (20). The invention also provides a method of manufacturing a monomode optical fiber. The fiber has a core that is better centered and less deformed than in the prior art. An application of the invention lies in making an optical amplifier.
Abstract:
An optical fiber amplifier is proposed comprising at least one pump light source (3), at least one amplifying fiber section (10), and at least one coupler (8) which establishes a connection between the input fiber (1) of the fiber type I, the pump light source (3), the amplifying fiber section (10), and the output fiber (12) of the fiber type I. The amplifying fiber section (10) consists of a fiber type II, and the the splices (2, 11) between the fiber type I and the fiber type II are arranged relative to the amplifying fiber section (10) such that light propagated in the direction opposite to the signal direction and light propagated in the signal direction passes through means absorbent of short wavelengths before it reaches the splices.