672results about "Glass fibre drawing apparatus" patented technology

A section of active optical fiber (11) which comprises an active core (1), an inner cladding layer (2) and an outer cladding layer (3). The diameter of said core 1) and the thickness of said inner cladding (2) change gradually along the length of said section of active optical fiber (11). This forms tapered longitudinal profile enabling a continuous mode conversion process along the length of the section of fiber (11). The method for fabricating a section of tapered active optical fiber comprises the steps of fabricating a preform for drawing active optical fiber from said preform, installing said preform into a drawing tower, drawing optical fiber in said drawing tower and altering at least one of the two parameters including the take-off preform speed and the take-up fiber speed during drawing of the optical fiber.

Improved method of and apparatus for joining and aggregating data elements integrated within a relational database management system (RDBMS) using a non-relational multi-dimensional data structure (MDD). The improved RDBMS system of the present invention can be used to realize achieving a significant increase in system performance (e.g. deceased access / search time), user flexibility and ease of use. The improved RDBMS system of the present invention can be used to realize an improved Data Warehouse for supporting on-line analytical processing (OLAP) operations or to realize an improved informational database system or the like.

The invention relates to a large-size optical fiber preform and a manufacturing method of the optical fiber thereof. A fluorine-doped liner tube is used as a base tube for depositing cladding layers and a core layer and is melted and shrunk into a solid mandril, and then the solid mandril and a sleeve form the preform; or the cladding layer part is deposited on the surface of the solid mandril to directly form the mandril to draw wire on a wire drawing tower. Wire drawing also can be carried out on the preform or solid mandril before stretching. During the wire drawing process, the optical fiber is coated with two layers of coating so as to obtain a mono-mode optical fiber with high anti-fatigue parameter, low water peak and insensitivity to bending. The manufacturing method has the advantages of large preform size, long wire drawing length of a single preform, relatively simple process and low cost and is remarkably suitable for scale production. The optical fiber manufactured by the method has a low water peak, extremely low optical loss caused by bending and relatively high anti-fatigue parameter and is particularly applicable to the optical fiber to be used when bent radius is small, such as an optical fiber access network (FTTx) or a small optical device.

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.

An optical article having a rare earth doped, fluorinated aluminosilicate glass core composition consisting essentially, in mole %, of:up to 15 weight % fluorine in the form of at least one of a fluorinated component of the glass composition and a batch constituent selected from a group consisting of at least one of AlF3, REF3, NH5F2, NaF, Na2SiF6, Na3AlF6,whereRE(1) is at least one of Y, La, Gd, and Lu;RE(2) is at least one of Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, and Tm;R is at least one of Ba, Ca, Mg, and Sr;(SiO2+GeO2) is in the range (40-90); and(Al2O3+Ga2O3)>(RO+"alk"2O+RE2O3) where "alk" is at least one of Li, Na, K, Cs, and Rb. A cullet-in-tube method for making continuous clad filament is also described.The invention provides for an optical waveguiding article having relatively high gain, a relatively flat gain spectrum, compatibility with conventional silica fiber, good durability and ease of manufacture.

A method for forming an optical fiber includes drawing the optical fiber from a glass supply and treating the fiber by maintaining the optical fiber in a treatment zone wherein the fiber is cooled at a specified cooling rate. The optical fiber treatment reduces the tendency of the optical fiber to increase in attenuation due to Rayleigh scattering, and / or over time following formation of the optical fiber due to heat aging. Methods for producing optical fibers along nonlinear paths incorporating fluid bearings are also provided thereby allowing for increased vertical space for the fiber treatment zone.