Corning Incorporated

Brett Jason Hoover

Ming-Jun Li

Karl William Koch, Iii

Michael Thomas Gallagher

Shenping Li

Leonard Charles Dabich, Ii

Daniel Warren Hawtof

Joel P Carberry

Joseph Edward McCarthy

Valery A Kozlov

Leonard Charles Ii Dabich

Karl W Iii Koch

According to one embodiment two-core optical fiber is provided for use in Brillouin distributed fiber sensor applications and systems. The two-core fiber includes a first and second core. Each core is configured to exhibit a Brillouin frequency shift greater than 30 Mhz relative to the other core. Further, each core possesses temperature and strain coefficients that differ from the other core. The cores can be configured to produce Brillouin frequency shift levels of at least 30 Mhz relative to one another. These differences in shift levels may be affected by adjustment of the material compositions, doping concentrations and/or refractive index profiles of each of the cores. These optical fibers may also be used in BOTDR- and BOTDA-based sensor systems and arrangements.

Two-core optical fibers for distributed fiber sensors and systems

Multi-core optical fiber ribbons and methods for making multi-core optical fiber ribbons are described herein. In one embodiment, a multi-core optical fiber ribbon includes at least two core members formed from silica-based glass and oriented in parallel with one another in a single plane. Adjacent core members have a center-to-center spacing &#x2267;15 microns and a cross-talk between adjacent core members is &#x2266;&#x2212;25 dB. In this embodiment each core member is single-moded with an index of refraction n, and a core diameter d. In an alternative embodiment, each core member is multi-moded and the center-to-center spacing between adjacent core members is &#x2267;25 microns. A single cladding layer is formed from silica-based glass and surrounds and is in direct contact with the core members. The single cladding layer is substantially rectangular in cross section with a thickness &#x2266;400 microns and an index of refraction n&#x3c;n.

Multi-core optical fiber ribbons and methods for making the same

A two-core optical fiber is provided for use in Brillouin distributed fiber sensor applications and systems. The two-core fiber includes a first and second core. Each core is configured to exhibit a Brillouin frequency shift greater than 30 Mhz relative to the other core. Further, each core possesses temperature and strain coefficients that differ from the other core. The cores can be configured to produce Brillouin frequency shift levels of at least 30 Mhz relative to one another. These differences in shift levels may be effected by adjustment of the material compositions, doping concentrations and/or refractive index profiles of each of the cores. These optical fibers may also be used in BOTDR- and BOTDA-based sensor systems and arrangements.

Multi-core optical fibers are disclosed herein. According to one embodiment, a multi-core optical fiber includes a common outer cladding formed from silica-based glass and having a cladding index of refraction n. At least one single mode core element may be disposed in the common outer cladding. The at least one single mode core element may have a maximum index of refraction n. In addition, at least one multimode core element may be disposed in the common outer cladding, the at least one multimode core element having a maximum index of refraction n. The maximum refractive index nof the at least one single mode core element may be greater than the cladding index of refraction n, the maximum refractive index nof the at least one multi-mode core element may be greater than n, and a center-to-center spacing between adjacent core elements is greater than or equal to 25 &#x3bc;m.

Multi-core optical fibers with single mode and multimode core elements

Multi-core optical fiber ribbons and methods for making multi-core optical fiber ribbons are described herein. In one embodiment, a multi-core optical fiber ribbon includes at least two core members formed from silica-based glass and oriented in parallel with one another in a single plane. Adjacent core members have a center-to-center spacing &#x2267;15 microns and a cross-talk between adjacent core members is &#x2266;&#x2212;25 dB. In this embodiment each core member is single-moded with an index of refraction n, and a core diameter d. In an alternative embodiment, each core member is multi-moded and the center-to-center spacing between adjacent core members is &#x2267;25 microns. A single cladding layer is formed from silica-based glass and surrounds and is in direct contact with the core members. The single cladding layer is substantially rectangular in cross section with a thickness &#x2266;400 microns and an index of refraction n&#x2266;n.

Polarization maintaining optical fibers and methods for making the same are disclosed herein. According to one embodiment, a polarization maintaining optical fiber includes a cladding portion and a core portion disposed in the cladding portion. The core portion includes a first core region having a first coefficient of thermal expansion CTE1 and a second core region having a second coefficient of thermal expansion CTE2. The first coefficient of thermal expansion CTE1 is not equal to the second coefficient of thermal expansion CTE2. At least one of the first core region and the second core region is non-circular symmetric with respect to a centerline of the polarization maintaining optical fiber.

Polarization maintaining optical fibers with intracore stress mechanisms

A preform for forming a hollow-core, slotted photonic band-gap (PBG) optical fiber for use in an environmental sensor, and methods of forming such a fiber using the preform are disclosed. The preform comprises a slotted cladding tube that surrounds a slotted, hollow-core PBG cane. The slots in the cladding tube and PBG cane are longitudinally formed and substantially aligned with each other. When the preform is drawn, the slots merge to form an elongated side opening or slot in the resulting hollow-core PBG fiber.

Pre-form for and methods of forming a hollow-core slotted PBG optical fiber for an environmental sensor

A method of fabricating a microstructure for an optical waveguide such as a photonic bandgap fiber is provided. The method includes the steps of assembling a stack of capillary tubes having substantially identical dimensions, fusing and redrawing the stack into a preform having a plurality of parallel holes of equal diameter, selecting a pattern of the holes for etching in order to increase their diameter, and plugging the unselected holes at one end of the preform against the flow of a pressurized etching fluid. Such plugging of the unselected holes is accomplished applying a layer of a gel-like sealant over the end of the preform, and then pushing the sealant into the holes to form sealant plugs in all of the holes. The sealant plugs are then removed from the selected holes by punching the sealant plugs out of the selected holes. The selected holes are then etched by conducting a pressurized flow of etching fluid to the end of the preform such that etching fluid flows only through the pattern of selected holes. The resulting preform is then fused and drawn into an optical waveguide, where the pattern of etched and unetched holes may form, for example, the microstructure for a photonic bandgap optical fiber.

Growing community of inventors

Middlebury Center, PA, United States of America

Brett Jason Hoover