Abstract: Under condition that a non-circularity ratio is 5% or lower and a thermal expansion coefficient of a glass which forms the core is &agr;1 and a thermal expansion of a glass which forms the cladding is &agr;2, the difference of coefficients is controlled such that a formula −2.5×10−7/° C.≦&agr;1−&agr;2≦1.0×10−7/° C. is satisfied so as to maintain a polarization mode dispersion to be 0.03 ps/km0.5 or lower. The difference of coefficients is further controlled such that a formula −1.5×10−7/° C.≦&agr;1−&agr;2≦0/° C. is satisfied so as to maintain a polarization mode dispersion to be 0.015 ps/km0.5 or lower. By doing this, birefringence is reduced by adjusting the thermal expansion coefficient in a core and a cladding; thus providing an optical fiber, and an optical transmission path using the optical fiber, having preferable PMD for high speed transmission.

Abstract: The present invention relates to an optical fiber having improved hydrogen-resistance properties. The optical fiber includes a high concentration germanium layer and a low concentration germanium layer. The high concentration germanium layer is disposed at a central position of the optical fiber and contains germanium oxide in a concentration of 0.1% by weight or more, relative to the total weight of the high concentration germanium layer. The low concentration germanium layer is disposed around the high concentration germanium layer and contains germanium oxide in a concentration of less than 0.1% by weight, relative to the total weight of the low concentration germanium layer. The ratio of optical power leaking from the high concentration germanium layer to the low concentration germanium layer in an employed wavelength band is 0.4% or less, relative to the total optical power propagating through the optical fiber.

Abstract: A single-mode optical fiber has a core and a cladding, and is produced in such a way that, when the radii of layers having individual refractive indexes are varied, more than one optical properties of the core, for example, the effective core area Aeff and the dispersion slope exhibit respective limiting values within a specific range of a reference radius. Such optical fibers provide basically the same optical properties but enable to vary the chromatic dispersion within a specific range so that the single-mode optical fiber is ideally suited for use in high-speed and large capacity communication systems.

Abstract: An optical fiber having a chromatic dispersion of +1.0 ps/nm/km or more in a 1460 nm wavelength band, a dispersion slope of 0.04 ps/nm2/km or more in a 1550 nm wavelength band, and a cutoff wavelength of 1450 nm or less, comprises a relation of an RDS, which is a value of the dispersion slope to the chromatic dispersion, to a wavelength &lgr; is −1.67×10−5&lgr;+0.0300≧RDS(&lgr;)≧−1.67×10−5&lgr;+0.0285.

Abstract: A manufacturing method and apparatus for manufacturing a coated optical fiber which has a superior surface smoothness of a resin coating and which can be coated with a colored ink with high coating performance. In the method including the steps of making a coated optical fiber by forming an outer coating layer around a bare optical fiber; and winding the coated optical fiber via pulleys by a take-up, the surface roughness of each solid body which the outer layer of the running coated optical fiber contacts is 0.8 &mgr;m or less. When the temperature of the outer coating layer is a room temperature or the Young's modulus of the outer coating layer is higher than 500 MPa, the surface roughness of each solid body, which the outer layer of the coated optical fiber contacts during drawing or rewinding, is 1.2 &mgr;m or less.

Abstract: An optical fiber coating die is made such that an interfacial shear rate of the optical fiber to the resin coat is calculated in accordance with a pressure value of resin inside a coating cup, and the interfacial shear rate is in a range of −1.5×105 to 0 sec−1. Also, an optical fiber drawing die is made such that the interfacial shear rate of the optical fiber to the resin coat is calculated in accordance with a diameter of a coating resin, and the interfacial shear rate is in a range of range of −3×105 to 2×105 sec−1. By doing this, an optical fiber drawing die which can be used in an optical fiber drawing method so as to realize stable resin coating operation even in high-speed drawing operation and high productivity can be realized.

Abstract: The present invention relates to a method for the production of a lutein-fatty acid ester concentrate of high purity by dissolving marigold oleoresin in a ketone solvent such as acetone, cooling the solution, and removing wherefrom a ketone solvent-insoluble component to uniform the quality of oleoresin, followed by dissolving the acetone-soluble portion obtained as above in butanol, cooling the solution, removing a butanol-soluble impurity after adding or without adding one or more members selected from the group consisting of water, methanol, ethanol and a mixture thereof, and washing the resulting butanol-insoluble with ethanol.

Abstract: An optical fiber is formed by performing vapor phase deposition of SiO2 on the outside of a glass rod comprising a core section and a first cladding section and drawing a glass preform which formed by a second cladding section. Also, a single mode optical fiber is manufactured so that the ratio of the diameter D of the first cladding section and the diameter d of the core section is in a range of 4.0 to 4.8, and OH concentration is 0.1 ppm or less. Also, an optical fiber is manufactured so that a value of D/d>4.8, and the OH concentration is 0.1 ppm or less. It is thereby possible to maintain an initial loss in the 1380 nm wavelength range even if hydrogen diffusion occurs.

Abstract: An optical fiber and an optical fiber preform having optical characteristics, such as the wavelength dispersion, close to design values by controlling the amount of change in the refractive index in the core, thereby realizing high-quality and high-speed transmission, and manufacturing methods therefor. The optical fiber or the optical fiber preform is manufactured in a manner such that at each position in the area in which the relative refractive index of the core with respect to the cladding is 80% or higher of the maximum value of the relative refractive index, the absolute value of the rate of change of the relative refractive index with respect to the position along the diameter of the cladding is 0.5 or less, where the position along the diameter of the cladding is defined by percentage with respect to the diameter.

Abstract: An improved method for manufacturing an optical fiber preform uses the CVD method in which a portion of or the whole of the optical fiber preform is formed by depositing glass on the inner wall of the starting tube. The method comprises a first step of depositing glass on the inner wall of the starting tube and collapsing the starting tube so that a silica rod is formed; a second step of removing the starting tube surrounding the silica rod or removing the starting tube and a part of synthetic glass; and a third step of depositing glass on an outer periphery of the silica rod obtained in the second step. By setting the refractive index of the cladding to be less than that of pure silica using the present method, an optical fiber having an extremely low transmission loss may be obtained.

Abstract: The present invention relates to an optical fiber having improved hydrogen-resistance properties. The optical fiber includes a high concentration germanium layer and a low concentration germanium layer. The high concentration germanium layer is disposed at a central position of the optical fiber and contains germanium oxide in a concentration of 0.1% by weight or more, relative to the total weight of the high concentration germanium layer. The low concentration germanium layer is disposed around the high concentration germanium layer and contains germanium oxide in a concentration of less than 0.1% by weight, relative to the total weight of the low concentration germanium layer. The ratio of optical power leaking from the high concentration germanium layer to the low concentration germanium layer in an employed wavelength band is 0.4% or less, relative to the total optical power propagating through the optical fiber.

Abstract: An information processing apparatus in accordance with the present invention includes a main body input and output section, provided to a main body cabinet section, for displaying a plan view of an object; and a lid body input and output section, provided to a lid body, for displaying a front view of the object. The main body cabinet section and the lid body are connected to each other by hinges so as to be opened and closed. A main control section is provided for changing a display state of the object on either the main body input and output section or the lid body input and output section in a predetermined manner, in response to a change in the display state of the object on the other input and output section.

Abstract: A sewing machine includes a sewing machine motor, a main shaft driven by the sewing machine motor, a sewing needle driven by the main shaft, a shuttle for capturing a thread loop in cooperation with the sewing needle, the shuttle having a hook shaft, a shuttle driving motor for driving the hook shaft of the shuttle independent of the sewing machine motor, a drive control device for controlling the sewing machine motor and shuttle driving motor so that the shuttle is rotated in synchronism with the main shaft, a thread jamming detecting device for detecting a thread jamming in the shuttle, and a releasing device for controlling the shuttle driving motor so that the shuttle is released from the thread jamming, when the thread jamming is detected by the thread jamming detecting device.

Abstract: A solid-state imaging device includes a plurality of sensor portions, and a vertical shift register corresponding to each of a series of sensor portions. A transfer electrode of the vertical shift register is formed of a first electrode and a second electrode which are repeatedly provided corresponding to the respective series of sensor portions and also formed continuously between the sensor portions adjacent to each other in the vertical direction. A signal charge is read out from each of the sensor portions through a portion below a read gate portion of the first electrode between sensor portions located in the vertical direction.

Abstract: A sewing system including a stitch-forming device including at least one sewing needle, for forming stitches on at least one workpiece; a feeding device which feeds at least one of the stitch-forming device and the workpiece relative to the other of the stitch-forming device and the workpiece along a reference plane; a control device which controls, according to at least one set of sewing data corresponding to at least one sewing pattern including a plurality of stitches, the stitch-forming device and the feeding device to form the stitches of the sewing pattern on the workpiece; a dimension-data memory which stores a plurality of sets of dimension data which correspond to a plurality of dimensions, respectively, each of which relates to the set of sewing data; and a selecting device which is operable for selecting one of the sets of dimension data stored in the dimension-data memory.

Abstract: An oscillating shuttle, including a shuttle race having a substantially annular guide groove including two end portions opposed to each other in a circumferential direction thereof, a shuttle body which includes a part-annular guided portion and a hook portion and which is oscillatory while the guided portion is guided by the guide groove, a driver which rotates the shuttle body about an axis line, wherein when the hook portion hooks a thread loop, the shuttle body is rotated by the driver in one of opposite directions such that the tail portion passes through one of the two end portions of the guide groove and enters an upper opening of the shuttle race and, when the shuttle body is rotated back in the other direction, a tail portion of the guided portion enters the one end portion of the guide groove, and at least one of the one end portion of the guide groove which has, in a direction parallel to the axis line, a width greater than a width of a remaining portion of the guide groove, and the tail portion of