Abstract: Provided is an erbium doped optical fiber (EDF) for amplification which allows an easy estimation of the amplification performance and high production stability. The fiber includes a core and a cladding. The core is mainly made of silica glass and doped with erbium at a concentration of 500 wtppm or more and 2500 wtppm or less. In the fiber, the cutoff wavelength is 850 nm or more and 1450 nm or less, the mode field diameter is 4.5 ?m or more and 6.5 ?m or less, the polarization mode dispersion is not more than 0.1 ps per 10 m, the coordination number of oxygen elements around an erbium element in the core is one or more and eight or less, and the bond length between erbium and oxygen is 0.225 nm or more and 0.235 or less.

Abstract: A haptic feedback input device includes a pair of driving levers journaled at a frame such that rotary shafts thereof are perpendicular to each other, an operating lever coupled to an intersection of the two driving levers such that it can rock, and a pair of rotary motors that apply feedback force to the operating lever via the two driving levers. In the haptic feedback input device, a pair of rotary encoders detect the relative dislocation amount of the operating level, and an absolute position detecting unit is composed of swing arms fixed to the two driving levers and photo interrupters that detect the existence of blocking portions formed at the swing arms and that output ON/OFF signals. A control unit calculates a reference position of the operating lever based on ON/OFF switching signals of the photo interrupters.

Abstract: The present invention relates to an optical amplification fiber and others capable of effectively reducing nonlinear interaction between signal channels even in transmission of multiplexed signal light containing multiple signal channels arranged in high density and also effectively reducing bending loss. An optical amplification module has an optical isolator, a WDM coupler, an Er-doped optical fiber (EDF) as an optical amplification fiber, a WDM coupler, and an optical isolator, which are arranged in order on a signal light propagation path from an input connector to an output connector, and further has a pumping light source connected to the WDM coupler and a pumping light source connected to the other WDM coupler. The EDF, at the wavelength of 1607 nm, has a mode field diameter (MFD) of 10 ?m or more to the fundamental mode and a MAC number (=MFD/cutoff wavelength) of 6.8 or less to the fundamental mode.

Abstract: An optical fiber bundle that has better ultraviolet resistance characteristics at a wavelength range of 150 to 250 nm and that can be readily and cheaply manufactured with no risk of, for example, explosion during manufacturing and its manufacturing method are provided. In the optical fiber bundle, optical fibers including a core mainly containing silica glass and a cladding containing silica glass and fluorine are bundled and accommodated in a container. This container has optically transparent ends, accommodates hydrogen or deuterium as well as the optical fibers, and is sealed. The capacity of the container is 10 times or less as large as the volume of glass of the optical fibers.

Abstract: An optical fiber can efficiently excite metallic ions by a pump lightwave, and an optical fiber amplifier and an optical fiber laser light source both incorporate the optical fiber. The optical fiber comprises (a) a solid region that has a first region doped with metallic ions and a second region surrounding the first region and that allows a lightwave for exciting the metallic ions to travel in a multiple mode and (b) a third region surrounding the second region and having a plurality of holes stretching along the length of the optical fiber. The optical fiber has a structure in which the first region is supplied with the power of a lightwave that is included in the pump lightwave and that is in a mode having no intensity peak at the center axis of the solid region.

Abstract: An optical fiber bundle that has better ultraviolet resistance characteristics at a wavelength range of 150 to 250 nm and that can be readily and cheaply manufactured with no risk of, for example, explosion during manufacturing and its manufacturing method are provided. In the optical fiber bundle, optical fibers including a core mainly containing silica glass and a cladding containing silica glass and fluorine are bundled and accommodated in a container. This container has optically transparent ends, accommodates hydrogen or deuterium as well as the optical fibers, and is sealed. The capacity of the container is 10 times or less as large as the volume of glass of the optical fibers.

Abstract: An optical component as an embodiment of the present invention comprises an optical waveguide. This optical waveguide is a single optical waveguide having a first position and a second position along a longitudinal direction thereof. In this optical waveguide, cross-sectional refractive index profiles vary along the longitudinal direction between the first position and the second position. In this optical waveguide, at a predetermined wavelength to become a single mode at the first position, an overlap rate between a field distribution of light having propagated from the first position and having arrived at the second position, and a Gaussian distribution is not less than 90%.

Abstract: The present invention relates to an optical fiber having a structure which allows further improvements to be made both in terms of lower reflectance and narrower bandwidth, and to a fiber grating type filter including the optical fiber. The optical fiber applied to the fiber grating type filter comprises a core region extending along a predetermined axis, and a cladding region provided on an outer periphery of the core region. The core region does not contain any photosensitive dopant which contributes to predetermined wavelength light photosensitivity as a glass property, but a part of the cladding region contain such a photosensitive dopant. By means of this composition, it is possible to form a grating, which has a grating plane slanted by a predetermined angle with respect to the optical axis, in a part of the cladding region surrounding the core region.

Abstract: The present invention provides fluorescent glass containing at least 50 mol % of at least one kind of oxide selected from the group consisting of SiO2, GeO2, and P2O5 as a glass constituent of a region containing a Bi ion as a dopant.

Abstract: Provided is an optical amplifier fiber in which both increasing output light power and sufficiently inhibiting the occurrence of nonlinear optical phenomenon can be compatibly achieved. In addition, an optical amplifier and light source equipment, in which such optical amplifier fiber is used, are provided. The optical amplifier fiber comprises (1) a core region doped with an aluminum element in the range of 1 wt % to 10 wt %, an erbium element in the range of 1000 wt. ppm to 5000 wt. ppm, and a fluorine element, the core region having an outer diameter in the range of 10 ?m to 30 ?m, and (2) a cladding region surrounding the core region and having a refractive index that is lower than the core region, wherein the relative refractive index difference of the core region relative to the cladding region is 0.3% or more and 2.0% or less.

Abstract: A method produces a glass body that contains a reduced amount of OH groups in the metallic-oxide-containing glass layer and that has a reduced amount of transmission loss due to OH groups when the glass body is transformed into an optical fiber. The production method produces an optical glass body. An optical fiber contains the optical glass body in at least one part of its region for guiding a lightwave. The production method includes the following steps: (a) introducing into a glass pipe a gas containing an organometallic compound and a glass-forming material; (b) decomposing the organometallic compound into an organic constituent and a metallic constituent; (c) heating and oxidizing the metallic constituent so that produced glass particles containing a metallic oxide are deposited on the inner surface of the glass pipe to form a glass-particle-deposited layer; and (d) consolidating the deposited layer to form a metallic-oxide-containing glass layer.

Abstract: An optical fiber bundle that has better ultraviolet resistance characteristics at a wavelength range of 150 to 250 nm and that can be readily and cheaply manufactured with no risk of, for example, explosion during manufacturing and its manufacturing method are provided. In the optical fiber bundle, optical fibers including a core mainly containing silica glass and a cladding containing silica glass and fluorine are bundled and accommodated in a container. This container has optically transparent ends, accommodates hydrogen or deuterium as well as the optical fibers, and is sealed. The capacity of the container is 10 times or less as large as the volume of glass of the optical fibers.

Abstract: A method of producing a glass blank with a high rate and high efficiency of deposition on a starting member is provided. A raw material powder including silica-glass-containing particles is transferred with a carrier gas and supplied into a flame, and the raw material powder and the flame are sprayed on a starting member to deposit the raw material powder on the starting member and form a porous body. The porous body is consolidated by heating.

Abstract: An optical fiber can efficiently excite metallic ions by a pump lightwave, and an optical fiber amplifier and an optical fiber laser light source both incorporate the optical fiber. The optical fiber comprises (a) a solid region that has a first region doped with metallic ions and a second region surrounding the first region and that allows a lightwave for exciting the metallic ions to travel in a multiple mode and (b) a third region surrounding the second region and having a plurality of holes stretching along the length of the optical fiber. The optical fiber has a structure in which the first region is supplied with the power of a lightwave that is included in the pump lightwave and that is in a mode having no intensity peak at the center axis of the solid region.

Abstract: Based on an intermediate 20A in which a cladding portion 22 is formed on the outer periphery of a core portion 21, a pair of holes 23 and 24 are provided parallel to the z axis on both sides of the core portion 21 within the cladding portion 22, and an intermediate 20 is thereby fabricated. In this intermediate 20, a width Ry in the y-axis direction is made smaller than a width Rx in the x-axis direction. Moreover, a cylindrical stress applying part 33 is inserted into a hole 23 of the intermediate 20, and a cylindrical stress applying part 34 is inserted into a hole 24 thereof. Thus, a preform 40 is formed. These materials are drawn and integrated together, and a polarization maintaining optical fiber is thereby manufactured.

Abstract: There is disclosed a method of manufacturing an optical fiber whose core is made of multi-component glass without fluctuation in its outer diameter and occurrence of sudden breakage thereof, with a technique of unifying a core rod and a cladding tube at the time of drawing, and yet drawing them; and the optical fiber having a multi-component glass core are disclosed.

Abstract: A method produces a glass body that contains a reduced amount of OH groups in the metallic-oxide-containing glass layer and that has a reduced amount of transmission loss due to OH groups when the glass body is transformed into an optical fiber. The production method produces an optical glass body. An optical fiber contains the optical glass body in at least one part of its region for guiding a lightwave. The production method includes the following steps: (a) introducing into a glass pipe a gas containing an organometallic compound and a glass-forming material; (b) decomposing the organometallic compound into an organic constituent and a metallic constituent; (c) heating and oxidizing the metallic constituent so that produced glass particles containing a metallic oxide are deposited on the inner surface of the glass pipe to form a glass-particle-deposited layer; and (d) consolidating the deposited layer to form a metallic-oxide-containing glass layer.

Abstract: The present invention relates to an optical waveguide and the like having a structure for generating a wide band of ASE. The optical waveguide comprises a material mainly comprised of glass or glass ceramics, and is at least partly doped with a rare earth element. In a spectrum of ASE generated in the optical waveguide when supplied with pumping light having a single wavelength in particular, a 15-dB band or 10-dB band includes a range from 1.45 ?m to 1.65 ?m or a range from 1.5 ?m to 1.7 ?m. Alternatively, a 3-dB band includes S, C, and L bands.

Abstract: A haptic feedback input device includes a pair of driving levers journaled at a frame such that rotary shafts thereof are perpendicular to each other, an operating lever coupled to an intersection of the two driving levers such that it can rock, and a pair of rotary motors that apply feedback force to the operating lever via the two driving levers. In the haptic feedback input device, a pair of rotary encoders detect the relative dislocation amount of the operating level, and an absolute position detecting unit is composed of swing arms fixed to the two driving levers and photo interrupters that detect the existence of blocking portions formed at the swing arms and that output ON/OFF signals. A control unit calculates a reference position of the operating lever based on ON/OFF switching signals of the photo interrupters.

Abstract: Provided are an optical fiber which exhibits a small increment of loss due to the OH group and which is suitable for transmitting signals in a band including a wavelength of 1,380 nm, and methods for manufacturing such optical fiber, an optical fiber preform, and a fluorine doped silica glass article. The fluorine doped silica glass article is produced by (1) depositing silica glass soot on a starting substrate to produce a silica glass soot deposit body and (2) heating the silica glass soot deposit body in an atmosphere including at least a first gas containing fluorine atoms and a second gas having deoxidizing property and containing no fluorine atom nor hydrogen atom. An optical fiber preform and an optical fiber are produced by the use of this glass body. The optical fiber has a clad containing fluorine and exhibits a transmission loss of 0.32 dB/km or less at a wavelength of 1,380 nm.