Abstract: An optical transmission fiber including a core having a first index of refraction, a cladding material located around the core and having a second index of refraction less than the first index of refraction, a first coating material located around a first portion of the cladding material and having a third index of refraction greater than the second index of refraction, and a second coating material located around a second portion of the cladding material and having a fourth index of refraction less than the second index of refraction.

Abstract: An optical transmission fiber including a core having a first index of refraction, a cladding material located around the core and having a second index of refraction less than the first index of refraction, a first coating material located around a first portion of the cladding material and having a third index of refraction greater than the second index of refraction, and a second coating material located around a second portion of the cladding material and having a fourth index of refraction less than the second index of refraction.

Abstract: An optical transmission fiber including a core having a first index of refraction, a cladding material located around the core and having a second index of refraction less than the first index of refraction, a first coating material located around a first portion of the cladding material and having a third index of refraction greater than the second index of refraction, and a second coating material located around a second portion of the cladding material and having a fourth index of refraction less than the second index of refraction.

Abstract: An optical transmission fiber including a core having a first index of refraction, a cladding material located around the core and having a second index of refraction less than the first index of refraction, a first coating material located around a first portion of the cladding material and having a third index of refraction greater than the second index of refraction, and a second coating material located around a second portion of the cladding material and having a fourth index of refraction less than the second index of refraction.

Abstract: An optical transmission fiber including a core having a first index of refraction, a cladding material located around the core and having a second index of refraction less than the first index of refraction, a first coating material located around a first portion of the cladding material and having a third index of refraction greater than the second index of refraction, and a second coating material located around a second portion of the cladding material and having a fourth index of refraction less than the second index of refraction.

Abstract: A tellurite glass particularly usable for an amplifier or oscillator utilizing an optical fiber or other guided wave structure. In approximate terms, the glass contain between 58 and 84 molar % of TeO.sub.2, up to 24 molar % Na.sub.2 O, and between 10 and 30 molar % of ZnO. Other alkali and divalent metals may be substituted for the Na and Zn respectively. Combinations of these tellurite glasses can be formed as an optical fiber (10) having a core (12) with a higher refractive index than that of the cladding (14). The tellurite glass of the core, when composed of at least 0.05 molar % Na.sub.2 O, can be doped with large amounts of Er, Pr, or Nd to act as a fiber amplifier at 1.5 or 1.3 .mu.m when pumped with light of a specified shorter wavelength. The core can be doped with other rare-earth metals which would provide optical amplifiers or oscillators at wavelengths appropriate to their lasing characteristics.

Abstract: Incorporation of fluorine into a porous silica body, such as an unsintered body produced by a sol-gel method, by VAD or OVPO, reduces or eliminates bubble or pore formation upon re-heating of the glass formed by sintering of the porous material. Effective fluorine concentrations are between 0.01 and 5% by weight. The invention can be used advantageously in producing preforms and optical fiber.

Abstract: Wide temperature range magnetic bubble memories are realized by using new compositions of rare earth garnets which require nonlinear bias field for operation over a given temperature range. The bias field structure for providing the corresponding nonlinear bias field includes plates of barium ferrite plus additional plates of Ni-Cu alloys and/or polycrystalline dysprosium (or other rare earths, singly or in combination) iron garnet to provide a nonlinear bias field versus temperature characteristic to match that of the bubble layer.

Abstract: Many ceramics are produced with a processing sequence that includes spray drying or ball milling a slurry. To produce ceramics with the best properties and to facilitate ball milling or spray drying, a dispersant is normally added to the ceramic slurry. Ammonium citrate and polyethylenimine have been found to produce ceramic slurries with the desired characteristics. The dispersants appear especially well suited for use with ferrite slurries.

Abstract: Many ceramics are produced with a processing sequence that includes spray drying or ball milling a slurry. To produce ceramics with the best properties and to facilitate ball milling or spray drying, a dispersant is normally added to the ceramic slurry. Ammonium citrate and polyethylenimine have been found to produce ceramic slurries with the desired characteristics. The dispersants appear especially well suited for use with ferrite slurries.