Nippon Telegraph and Telephone Corporation

Japan Aviation Electronics Industry, Limited

Nippon Telegraph and Telephone Public Corporation

Ntt Advanced Technology Corporation

Juichi Noda

Hiroaki Hanafusa

Yoshiaki Takeuchi

Hiroyuki Sasaki

Masato Shimamura

Etsuji Sugita

Nobuo Tomita

Taisuke Oguchi

Koichi Fujiwara

Shiro Nishi

Ryo Nagase

Katsunari Okamoto

Takao Edahiro

Kazunori Naganuma

Hitoshi Goto

Taisei Miyake

Hiromichi Mizutani, Deceased

Itaru Yokohama

Yoshio Noguchi

Mitsuhiro Tateda

Kazumasa Takada

Yutaka Sasaki

Hiroko Mizutani

Noriyoshi Yamada

Haruo Nagai

Ai Fukuhara

Isao Iwakane

Toshihito Hosaka

Yuji Takaoka

Kazunori Chida

Hiromichi Mizutani

Hiroko Misutani

Yamada Noriyoshi

Kou Niida

A cleaning tool for cleaning optical fiber connectors exposes a cleaning sheet in a window of the case. A winding pulley is operable to wind the cleaning sheet upon rotation at a constant pitch. A rotation mechanism, that is operated by a lever, rotates the winding pulley. The case is constructed of a first front plate and a second front plate which are closed off by a perimeter wall along their outer circumference. The case has an open portion in a part of the perimeter wall, and the lever is disposed in the open portion in an inclined orientation.

Cleaning tool for optical fiber connectors

A dielectric multilayer filter applicable to optical communication systems is disclosed, as is a fabrication method therefor, and an optical element incorporating the same. The disclosed dielectric multilayer filter includes a fluorinated polyimide base layer with a dielectric multilayer formed thereover. According to the disclosed fabrication method, a fluorinated polyimide layer is formed by applying liquid fluorinated polyimide material over a smooth surface to a predetermined thickness followed by drying and hardening, after which a dielectric multilayer is formed over the fluorinated polyimide layer by an ion assist vapor deposition method, and then stripping the fluorinated polyimide layer away from the underlying smooth surface. The disclosed dielectric multilayer filter can be easily and economically produced at a suitably small thickness with no need for grinding, exhibits highly uniform physical and optical properties, and is exceedingly durable and resistant to curling and warping.

Method of fabricating a dielectric multilayer filter

Laser magnetic immunoassay method and apparatus therefor

A laser magnetic immunoassay (LMIA) method which enables detection of less than picograms of target analyte in milliliter of analyte solution. The method involves the steps of: affixing an antibody or antigen on the surface of non-magnetic carrier particles; immunoreacting the affixed antibody or antigen to capture a target analyte contained in a specimen; preparing magnetic labeled microparticles treated so as to bind with the target analyte; reacting the labeled complex to sandwich the target analyte between the magnetic particles and the non-magnetic carrier particles; separating the free species from the bound species by centrifugation; dispersing the precipitated solid to make an analyte solution; applying a spot magnetic field gradient on the analyte solution and irradiating a selected spot with a laser beam; and analyzing the resulting interference patterns to quantitatively determine the quantity of target analyte.

Laser magnetic immunoassay method and apparatus thereof

Dielectric multilayer, filter, manufacturing method therefor, and

Two single mode optical fibers are reduced in diameter over a predetermined length to form reduced-diameter portions whose center portions have different diameters. The two optical fibers are intersected at a small angle to each other substantially centrally of their reduced-diameter portions and then are fused together at the intersecting portions and the fused portions of the two optical fibers are heated and stretched to provide an optical coupler having a desired coupling ratio.

Wide-band optical fiber coupler and its manufacturing method

Two single mode optical fibers are stretched to form prestretched portions of different diameters, and then the optical fibers are fused together at their prestretched portions to form a coupling region which is stretched to obtain a wide-band optical fiber coupler of a desired splitting ratio.

A ferrule for optical fibers transmitting linearly polarized light capable of preventing deterioration and fluctuation of the extinction ratio. The ferrule incorporates at least two paths connecting a region in a vicinity of an end of a puncture for an optical fiber inside the flange portion with outside of the ferrule. These paths effectively enable the removal of air in such a region which could have caused an extraneous stress on the optical fiber resulting in deterioration of the extinction ratio. An optical fiber connector using this ferrule is also disclosed.

Ferrule for optical fiber transmitting linearly polarized light and

In a method of making an optical fiber coupler through heat elongation of optical fibers, the performance of the coupled optical fibers is measured after the optical fibers are heat elongated at least once, and based on the measured elongation length and the performance of the coupled optical fibers, a functional equation representing their relationship is determined by approximate calculation. The functional equation is used to calculate an elongation length which provides the intended performance of the coupled optical fibers, and then the optical fibers are heat elongated to the calculated length.

Method for the manufacture of an optical fiber coupler

According to this invention, a superluminescent diode includes a current injection portion having a current injection electrode formed adjacent to a first end face, a light-absorption portion contiguous with the current injection portion; and a waveguide continuously formed to extend from the current injection portion to the light-absorption portion. The waveguide is constituted by an active layer and a member which completely buries the active layer, has a bandgap larger than that of the active layer, and is formed of a material having a small refractive index. The waveguide of the current injection portion is linearly formed to be perpendicular to the first end face. The waveguide of the light-absorption portion has an end portion for guiding reflected light in a direction different from a propagation direction of light propagating through the waveguide.

Superluminescent diode

A fiber coupler includes first and second optical fiber groups and a fused-elongated region. The first optical fiber group is obtained by parallelly arranging a plurality of optical fibers on a single plane, a coating of each of the optical fibers being removed throughout a predetermined portion at the same position as that of an adjacent optical fiber in a longitudinal direction. The second optical fiber group is obtained by parallelly arranging adjacent optical fibers on a predetermined plane parallel to an arrange plane of the first optical fiber group at the same pitch as that of the first optical fiber group, a coating of each of the optical fibers being removed throughout a predetermined portion at the same position as that of an adjacent optical fiber in a longitudinal direction as the first optical fiber group. The fused-elongated region is located at a portion of the predetermined portions from which the coatings are removed and obtained by fusing/elongating at least some optical fibers of the first optical fiber group with at least some optical fibers of the second optical fiber group so that corresponding optical fibers are fused/elongated. A plane including centers of two cores of the optical fibers fused with each other at the fused-elongated region is arranged substantially perpendicular to the arrange planes of said first and second optical fiber groups, and at least a portion of the first and/or second optical fiber groups is a fiber ribbon obtained by integrally forming a plurality of optical fibers each having a core and a clad by a coating.

Fiber coupler and method and apparatus for manufacturing the same

A method and apparatus for measuring ultrashort optical pulses is described. Pulse waveforms to be measured are the type which vary at high speed in a time close to or less than the response time of an optical detector. Changes of optical wavelength or frequency are measured at various sections of that pulse. The light to be measured is split into two beams, and recombined after provided with different delay times, respectively. The combined light is caused to enter a doubling crystal to generate a second-harmonic light, and the second-harmonic light component, or both the second-harmonic and fundamental components, is measured. The intensity shape and chirping of the pulses is obtained from the changes in the intensity of these components as a function of delay time difference by Fourier analysis including iterative arithmetic operations.

Method and apparatus for measuring ultrashort optical pulses

A single-polarization single mode optical fiber of the type comprising an elliptical core, a pair of stress applying parts on both sides of the minor radius of the elliptical core for applying asymmetrical stress thereto and a clad embedding therein the core and the stress applying parts, the stress applying parts being made of B.sub.2 O.sub.3 wherein a relative refractive index difference .DELTA. between the core and the clad satisfies a relation 0.004.ltoreq..DELTA..ltoreq.0.05, an ellipticity .epsilon. satisfies a relation 0.01.ltoreq..epsilon..ltoreq.0.9, the B.sub.2 O.sub.3 has a molar concentration of 1 to 25 mole %, ratio of thickness of the stress applying parts and the core is 5 to 15, a modal birefringence B expressed by an equation B=(.beta..sub.x -.beta..sub.y)/k satisfies a relation B=1.times.10.sup.-6 where (.beta..sub.x -.beta..sub.y) represents a propagation constant difference between HE.sub.11.sup.x and HE.sub.11.sup.y modes, and k a wave number in vacuum, whereby a polarization mode dispersion, that is a delay time difference between the HE.sub.11.sup.x and HE.sub.11.sup.y modes which are orthogonal with each other is zero.

Single-polarization single-mode optical fiber

Growing community of inventors

Mito, Japan

Juichi Noda