Abstract:
According to one example of the invention an optical fiber comprises: (i) silica based, rare earth doped core having a first index of refraction n1; (ii) at least one silica based cladding surrounding the core and having a second index of refraction n2, such that n1> n2 with the following features, alone or in combination: said cladding includes 0.5 to 5 wt% F and 0.5 to 20 wt% B, said optical fiber has less than 8dB/km core background loss at a wavelength of 1280 nm. at least one of the core or cladding is doped with AI203 concentration is less than 2:1.
Abstract:
The present invention concerns a preform for an optical fibre, an optical fibre so obtained and methods for making the same. The fibre is characterized in that porous glass doped with at least one dopant for adsorbing light is used. Resulting fibres can be used to make high attenuation fibres. The expression porous glass designates only glasses containing a plurality of interconnected micro-pores obtained by phase separation, e.g. of a boro-silcate glass, not porous soot obtained by a CVD process.
Abstract:
Die vorliegende Erfindung betrifft eine Glasfaser, welche einen Kern umfasst, dessen Matrixglas mindestens ein Schwermetalloxid und mindestens eine Seltene Erden-Verbindung enthält, wobei der Kern von mindestens zwei Glasmänteln umgeben ist. Ferner betrifft die vorliegende Erfindung ein Verfahren zur Herstellung einer erfindungsgemässen Glasfaser, einen optischen Verstärker, welcher mindestens eine erfindungsgemässe Glasfaser umfasst, sowie die Verwendung der erfindungsgemässen Glasfaser.
Abstract:
A borosilicate glass composition comprises SiO2 having a concentration of about 40 mole percent to about 60 mole percent, B2O3 having a concentration of about 10 mole percent to about 30 mole percent, and an alkaline earth and/or alkali compound having a concentration of 10 mole percent to about 40 mole percent. An optical fiber amplification device comprises a borosilicate glass material cladding. The core comprises a germanate glass material doped with Tm3+. The germanate glass material has a first surface configured to receive an optical signal having a wavelength of from about 1400 nm to about 1540 nm and a second surface configured to output an amplified optical signal. In this manner, low cost fiber amplifiers in the 1450-1530 nm wavelength region (corresponding to the S-band) can be achieved.
Abstract:
The invention features high index-contrast fiber waveguides (1301) that can be drawn from a preform. The invention also features materials for forming high index-contrast fiber waveguides (1301), and guidelines for their selection. High index-contrast fiber waveguides (1301), which may include opical fibers and photonic crystal fibers, can provide enhanced radial confinement of an optical signal in the fiber waveguide (1301). Moreover, large optical energy densities can be achieved inside the high index-contrast fiber waveguides, making them attractive candidates for a number of applications.
Abstract:
High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides are disclosed. In one of the aspect of the invention, a high index-contrast fiber (701) includes a core (710) with refractive index n1 extending along a waveguide axis and a cladding layer (720) surrounding core (710) having an index of refraction n2. The core (710) incldues a hhigh index material, e.g., a chalcogenide glass and the cladding layer (720) includes a low index material, e.g., an oxide glass and/or halide hglass. The absolute difference between n1 and n2 is at least 0.35.
Abstract:
High index-contrast fiber waveguides (701) having a core (710) and a cladding (720), material for forming high index-contrast fiber waveguides (701), and applications of high index-contrast fiber waveguides (701) are disclosed.
Abstract:
A method of creating a codoped layer (18) includes creating a first layer (14) having a first dopant and at least one other layer (16) have another dopant, then interdiffusing the dopant to create a substantially homogeneous codoped layer. More than one dopant may be deposited in a single layer. The creating conditions may be optimized for each layer (14, 16). Further, when the creation of a layer includes sequential deposition and consolidation, conditions for each process may be optimized within the layer creation. While at least two layers (14, 16) are formed, the interdiffusion substantially eliminates any stratification or layer structure.
Abstract:
This process provides a new way to embed rare earth fluorides into silica (or germania-doped silica) glasses by solution chemistry. Embedding rare earth fluorides into a silica (or germania-doped silica) glasses comprises the following steps. The first step forms a porous silica core preform by OVD process. The second step submerges the preform into an aqueous solution of rare earth ions. The third step removes the preform from the solution and washes the outside surfaces of the preform. The fourth step submerges the preform into an aqueous solution of a fluorinating agent, such as ammonium bifluoride, HF or KF. Rare earth trifluorides precipitate out from the solution and deposit on the wall of pores. This is followed by drying.