摘要:
The present invention relates to a method of manufacturing an optical fiber preform for obtaining an optical fiber with low transmission loss. A core preform included in the optical fiber preform comprises three or more core portions, which are each produced by a rod-in-collapse method, and in which both their alkali metal element concentration and chlorine concentration are independently controlled. In two or more manufacturing steps of the manufacturing steps for each of the three or more core portions, an alkali metal element is added. As a result, the mean alkali metal element concentration in the whole core preform is controlled to 7 atomic ppm or more and 70 atomic ppm or less.
摘要:
The subject of the invention is a method for manufacturing a final optical fiber preform via overcladding of a primary preform having a cross section area, the method comprising at least one manufacturing step of the primary preform by deposit of an inner cladding and of a central core inside a tube of Fluorine-doped silica, the tube being chosen such that it has a cross section area that is maximally 15 % less than the cross section area of the primary preform. With the method of the invention it is possible to manufacture a preform of large capacity at reduced cost which allows the drawing of an optical fiber having reduced transmission losses.
摘要:
An optical waveguide (11) includes a region (22) which, after electrical poling of a guiding region (16), maintains an internal electric field induced by the poling potential. The internal electric field may arise from charge separation between regions (18, 20) induced by an adjacent poling electrode (12A), and region (22) acts to inhibit decay of the space charge and to increase the lifetime of the induced electro-optic effect. The waveguide may comprise a twin hole optical fiber (11) with internal electrodes (12A, 14A), where the region (22) comprises a borosilicate layer concentrically disposed about one of the electrodes.
摘要:
An optical waveguide (11) includes a region (22) which, after electrical poling of a guiding region (16), maintains an internal electric field induced by the poling potential. The internal electric field may arise from charge separation between regions (18, 20) induced by an adjacent poling electrode (12A), and region (22) acts to inhibit decay of the space charge and to increase the lifetime of the induced electro-optic effect. The waveguide may comprise a twin hole optical fiber (11) with internal electrodes (12A, 14A), where the region (22) comprises a borosilicate layer concentrically disposed about one of the electrodes.
摘要:
A device for manufacturing an optical preform by means of an internal vapour deposition process, the device comprising an energy source and a hollow substrate tube, which hollow substrate tube has a supply side and a discharge side, the energy source being moveable along a length of the hollow substrate tube, the device further comprising an elongation tube connected to the hollow substrate tube at the discharge side thereof wherein the hollow substrate tube extends into an interior of the elongation tube and in that an internal diameter of the elongation tube is at least 0,5 millimeter larger than an external diameter of the hollow substrate tube.