Abstract: A dispersion compensating module, mode converter, coupler and dispersion compensated optical fiber therein. The dispersion compensating fiber has a plurality of core segments, the refractive index profile being selected to exhibit properties such that an LP02 mode at 1550 nm may be propagated a distance (generally 0.5-3.0 km), upon conversion to LP02, to compensate for dispersion of a length of transmission waveguide preferably greater than 25 km propagating in an LP01 mode. In another embodiment, the dispersion compensating module has a mode converter having a reflective fiber grating for converting a first to a second mode interconnected to a dispersion compensated fiber propagating in the second mode. The mode converter has a coupler adapted to operatively couple light propagating in a first mode from a first fiber into a second, and a reflective fiber grating operatively coupled to the second fiber; the grating being capable of converting light from the first into the second mode.

Abstract: An optical fibre has a cladding layer surrounding a core, the cladding layer comprising at least a first, relatively inner generally cylindrical region, a third, relatively outer generally cylindrical region, and a second region disposed between the first and third regions, the second region having a higher refractive index than the first and third regions; and the peak difference in refractive index between the first cladding region and the core being less than about 0.0030.

Abstract: A printing unit, a sheet-feeding unit, a sheet-discharging unit, an ink-feeding unit and a roller-oscillating unit of a digital printing press are adapted to receive the driving force from a common motor. An image-forming device fixedly mounted on the digital printing press is adapted to form images on printing plates mounted on the printing unit as the plate cylinder rotates upon receiving the driving force from the common motor. The transmission of the driving force to at least two of the sheet-feeding unit, the sheet-discharging unit, the ink-feeding unit and the roller-oscillating unit is shut off by means of a single clutch during the image-forming operation.

Abstract: This invention produces a film which is resistant to hillocking without compromising the electrical conductivity of the interconnects, the circuit architecture or any other function affecting the operation of the integrated circuit. The invention works on the principle that hillocking is caused by the squeezing or extrusion of certain grains (crystals) in the film due to a compressive residual stress state that arises from annealing (heating) treatments applied to the film following the deposition of the film. These grains are in a “weak” crystallographic orientation relative to the great majority of the grains. The coordinated orientation of this great majority of grains is known as the texture and aluminum films are deposited with a strong (111) texture, where (111) refers to specific crystallographic planes and <111>. Refers to the direction normal to the (111) plane.

Abstract: A dispersion compensating module, mode converter, coupler and dispersion compensated optical fiber therein. The dispersion compensating fiber has a plurality of core segments, the refractive index profile being selected to exhibit properties such that an LP02 mode at 1550 nm may be propagated a distance (generally 0.5-3.0 km), upon conversion to LP02, to compensate for dispersion of a length of transmission waveguide preferably greater than 25 km propagating in an LP01 mode. In another embodiment, the dispersion compensating module has a mode converter having a reflective fiber grating for converting a first to a second mode interconnected to a dispersion compensated fiber propagating in the second mode. The mode converter has a coupler adapted to operatively couple light propagating in a first mode from a first fiber into a second, and a reflective fiber grating operatively coupled to the second fiber; the grating being capable of converting light from the first into the second mode.

Abstract: A dispersion compensating module, mode converter, coupler and dispersion compensated optical fiber therein. The dispersion compensating fiber has a plurality of core segments, the refractive index profile being selected to exhibit properties such that an LP02 mode at 1550 nm may be propagated a distance (generally 0.5-3.0 km), upon conversion to LP02, to compensate for dispersion of a length of transmission waveguide preferably greater than 25 km propagating in an LP01 mode. In another embodiment, the dispersion compensating module has a mode converter having a reflective fiber grating for converting a first to a second mode interconnected to a dispersion compensated fiber propagating in the second mode. The mode converter has a coupler adapted to operatively couple light propagating in a first mode from a first fiber into a second, and a reflective fiber grating operatively coupled to the second fiber; the grating being capable of converting light from the first into the second mode.

Abstract: Disclosed is a fiber optic filter that includes a central core, a ring core concentric with the central core, an inner cladding region of refractive index ni between the central and ring cores, and a cladding layer of refractive index nc surrounding the ring core. The maximum refractive index n1 of the central core and the maximum refractive index n2 of the ring core are greater than nc and ni. The propagation constants of one core mode and one ring mode are different at wavelengths except for at least one wavelength &lgr;0 whereby power transfers between the two cores at &lgr;0. At least a portion of the fiber optic filter fiber is wound around a reel to subject it to a continuous curvature, the radius of which determines the amplitude of the attenuation. Such fibers are useful in fiber amplifiers in which the central core contains active dopant ions.

Abstract: A printing unit, a sheet-feeding unit, a sheet-discharging unit, an ink-feeding unit and a roller-oscillating unit of a digital printing press are adapted to receive the driving force from a common motor. An image-forming device fixedly mounted on the digital printing press is adapted to form images on printing plates mounted on the printing unit as the plate cylinder rotates upon receiving the driving force from the common motor. The transmission of the driving force to at least two of the sheet-feeding unit, the sheet-discharging unit, the ink-feeding unit and the roller-oscillating unit is shut off by means of a single clutch during the image-forming operation.

Abstract: An optical waveguiding fiber has a photosensitive core and a cladding that includes a photosensitive inner cladding region adjacent the core and an outer cladding region. The inner cladding region and the outer cladding region have substantially equal indices of refraction. The photosensitivity of the inner cladding region is sufficient to cause a modulation of the index of refraction of the inner cladding when exposed to ultraviolet light. In another aspect of the invention, the optical fiber includes a grating in the core, which extends radially into the inner cladding region. The core and the inner cladding region of the optical fiber are doped with concentrations of Ge and B sufficient to impart photosensitivity to the inner cladding region, and to result in an index of refraction in the inner cladding region substantially equal to the index of refraction of the outer cladding region.

Abstract: An optical fibre has a cladding layer surrounding a core, the cladding layer comprising at least a first, relatively inner generally cylindrical region, a third, relatively outer generally cylindrical region, and a second region disposed between the first and third regions, the second region having a higher refractive index than the first and third regions; and the peak difference in refractive index between the first cladding region and the core being less than about 0.0030.

Abstract: Disclosed is a fiber optic filter that includes a central core, a ring core concentric with the central core, an inner cladding region of refractive index ni between the central and ring cores, and a cladding layer of refractive index nc surrounding the ring core. The maximum refractive index n1 of the central core and the maximum refractive index n2 of the ring core are greater than nc and ni. The propagation constants of one core mode and one ring mode are different at wavelengths except for at least one wavelength &lgr;O whereby power transfers between the two cores at &lgr;O. At least a portion of the fiber optic filter fiber is wound around a reel to subject it to a continuous curvature, the radius of which determines the amplitude of the attenuation. Such fibers are useful in fiber amplifiers in which the central core contains active dopant ions.

Abstract: PURPOSE: To increase the mechanical strength of a connected optical fiber, by carrying out a surface treatment by dipping the melt-struck connection part of the optical fiber in a treating liquid of strong acid and then in a treating liquid of hydrofluoric acid. CONSTITUTION: A treatment liquid 6 of a mixture solution consisting of 1 or ≧2 kinds of strong acid such as sulfuric acid, hydrochloric acid, nitric acid, etc. is stored in a liquid tank 7. A melt-stuck connection part 5 of end parts 2A and 2B of optical fibers 1A and 1B is dipped in the tank 7. Thus coat residue, dust, metallic particles, etc. sticking to the surface of the part 5 are removed. Then the part 5 is dipped in a treating liquid containing an aqueous solution of hydrofluoric acid, ammonium fluoride, sodium fluoride in a liquid tank 8. Thus the minute flaws on the surface are removed or annealed. As a result, the strength is increased at the part 5.

Abstract: An optical fiber coupler has at least an m-core optical fiber optically coupled to an n-core optical fiber, where m and n are positive integers and m is greater than 1. A channel add/drop multiplexer includes an optical fiber coupler and a Bragg grating disposed on the m-core fiber outside the coupling region.

Abstract: A Bragg grating filter is provided for use in an optical fiber of an optical fiber system. The optical fiber includes a core and a cladding. A plurality of Bragg grating segments are formed into the core of the optical fiber. Each grating element is defined by periodic variations in the refractive index. The period variations in the refractive index have a spatially asymmetric index of modulation, such that dispersion of the reflection at one end of the grating element can be decreased at the expense of increased dispersion of reflection at the other end of the grating element.

Abstract: Disclosed is a fiber optic filter that includes a central core, a ring core concentric with the central core, an inner cladding region of refractive index ni between the central and ring cores, and a cladding layer of refractive index n, surrounding the ring core. The maximum refractive index n, of the central core and the maximum refractive index n2 of the ring core are greater than nc and ni. The propagation constants of one core mode and one ring mode are different at wavelengths except for at least one wavelength &lgr;0 whereby power transfers between the two cores at &lgr;0. At least a portion of the fiber optic filter fiber is wound around a reel to subject it to a continuous curvature, the radius of which determines the amplitude of the attenuation. Such fibers are useful in fiber amplifiers in which the central core contains active dopant ions.

Abstract: The invention provides a method of manufacturing a chirped optical fiber grating, the method comprising the steps of an etching the cladding of the optical fiber to vary the cross-sectional area of a portion of an optical fiber, and impressing a grating of uniform pitch on the portion of the fiber in which the portion of the fiber is subjected to different respective longitudinal forces during the impressing step and during subsequent use of the grating.

Abstract: Tin-doped photosensitive optical glass is disclosed, together with applications of the glass in fabricating waveguides and waveguide devices such as Bragg gratings.

Abstract: An optical fiber comprises a glass core having a core refractive index; a glass primary cladding at least partially surrounding said core, said primary cladding having a primary cladding refractive index lower than said core refractive index; a glass secondary cladding at least partially surrounding said primary cladding, said secondary cladding having a secondary cladding refractive index lower than said core refractive index but higher than said primary cladding refractive index; said glass of said core and said glass of at least part of said primary cladding containing one or more photosensitizing dopants.

Abstract: An optical fiber has a cladding glass layer surrounding a glass core, in which a region (preferably annular) of the optical fiber partially overlapping the cladding and/or the core is formed of photosensitive glass.