Abstract: Non-oxide or heavy metal fluoride glass optical fiber with or without a cladding and coated with an outer layer of an oxide glass having a glass transition temperature of less than 400.degree. C. and a thermal expansion coefficient of less than about 19.times.10.sup.-6.C.sup.-1. Also, a method of making and providing such coatings on non-oxide or fluoride glass, and fiber optic products prepared by such methods.

Abstract: Non-oxide or heavy metal fluoride glass optical fiber with or without a cladding and coated with an outer layer of an oxide glass having a glass transition temperature of less than 400.degree. C. and a thermal expansion coefficient of less than about 19.times.10.sup.-6 .degree. C..sup.-1. Also, a method of making and providing such coatings on non-oxide or fluoride glass, and fiber optic products prepared by such methods.

Abstract: A hermetically sealed optical fiber product comprising a fluoride or other non-silica based glass optical fiber and a hermetic coating of carbon, a metal, a fluoride, a metalloid or a ceramic compound in a thickness sufficient to impart moisture resistance to the optical fiber product.

Abstract: An improved torch for the mixing of oxidant and fuel gases external to the torch, for exampled for use in chemical vapor deposition processes, and its method of manufacture are disclosed. A first torch body portion is formed having a manifold cavity with one side open. A number of tubes extend from passages formed in a torch face plate through the first manifold cavity. A first liquid material (such as wax) is poured into the cavity, such that its upper surface defines the desired inside wall surface of the first manifold corresponding to the open side. This material is allowed to harden. A second liquid material (such as epoxy) is then poured over the first material, and hardens to form the remaining wall of the first manifold cavity and to seal the tubes to the torch body portion. The first material is then removed, providing a torch body portion having a manifold with tubes extending through it. A second manifold may then be assembled to the first torch body portion to provide connection to the tubes.

Abstract: A composite capillary tube structure made of a plurality of glass layers and methods for making same. This composite includes inner and outer layers of fused silica glass separated by an intermediate layer of a glass material having a higher coefficient of thermal expansion than the fused silica glass. The glass material of the intermediate layer also has a glass transition temperature on the same order as that of fused silica, so that the fused silica layers are maintained under compressive forces over a temperature range of up to about 400.degree. C. Preferably, the intermediate layer is a borosilicate or aluminosilicate glass.

Abstract: Pressure or strain sensitive optical fiber having a core, at least a portion of which has a predetermined refractive index for transmitting light therethrough, a cladding adjacent the core having a refractive index which is less than that of the core, and a concentric light transmissive layer adjacent the cladding having a refractive index which is greater than that of the cladding. The light transmissive layer has an internal diameter which is greater than the unperturbed mode boundary diameter of the core, such that all light passes through the core when the fiber is unperturbed. When the optical fiber is subjected to pressure forces in the form of stress or strain, light passes through the light transmissive layer in proportion to the amount of stress or strain acting upon the fiber. Also, pressor sensors and methods for measuring forces or pertubations utilizing such optical fiber.

Abstract: A method for hermetically sealing a silica based fiber product after the fiber product has been drawn from a melt or preform wherein a hermetic layer of boron carbide or a ceramic compound having a density of above about 4 g/cc is deposited upon the fiber product. The fiber product can be initially coated with carbon or boron carbide prior to the application of the ceramic compound. Also, a method for making such fiber products using these methods, and the resultant hermetically sealed fiber products produced thereby.

Abstract: An arrangement for an optical fiber pressure sensor is described. This sensor is comprised of two coating layers concentrically clad to and coaxially oriented with an optical fiber. The first coating layer is comprised of a relatively hard optically lossy material which absorbs any light radiating outwardly from the optical fiber. The second coating layer is comprised of a compliant material in which granular particles have been uniformly dispersed. In response to any pressure laterally applied to the sensor, the compliant coating layer imparts micro-bends, onto the optical fiber, which, in turn, couple light from propagating modes to non-propagating modes. As a result, the amplitude (or power) of the light exiting the optical fiber advantageously decreases in response to this pressure.

Abstract: A concentric core optical fiber comprised of an inorganic crystalline, preferably metallic, central core and an optical waveguide having an optical ring core and inner- and outer-glass cladding layers concentrically clad to the central core is described. A long length of such an optical fiber can advantageously support a heavy load for a substantial period of time without fatiguing while providing a transmission medium for optical and/or electrical signals.

Abstract: A magnetically sensitive optical fiber is described. Specifically, this fiber is comprised of a central core containing magnetostrictive material and an optical waveguide, having an optical ring core and inner- and outer-glass cladding layers, clad to the central core. The core is constructed from magnetostrictive material which is readily and inexpensively available as wire of various gauges. The wire is chosen to have a relatively large cross-sectional area with respect to that of the glass cladding layer(s). The resulting optical fiber is advantageously highly sensitive to weak magnetic fields and is also both simple and inexpensive to manufacture.