Abstract: An optical fiber having excellent strength that can be manufactured at low cost, as well as a method for making such optical fiber, is provided. An optical fiber 1 is a silica-based optical fiber comprising a core 11, an optical cladding 12 surrounding the core 11, and a jacketing region 13 surrounding the optical cladding 12 and having a uniform composition throughout from the internal circumference to the outer circumference. A compressive strained layer having a residual compressive stress is provided at the outermost circumference of the jacketing region 13.

Abstract: There is provided a method for producing an optical fiber preform used in producing an optical fiber having low attenuation. The production method includes (1) a rod formation step of forming a glass rod of a silica glass containing an alkali metal element, the average concentration of the alkali metal element being 5 at·ppm or more, (2) a heat treatment step of heat-treating the glass rod, (3) a core part formation step of forming an alkali metal element-free silica glass layer having a chlorine concentration of 6000 at·ppm or more around the perimeter of the glass rod heat-treated in the heat treatment step to form a core part including the glass rod and the silica glass layer, and (4) a cladding part formation step of forming a cladding part of a silica-based glass having a lower refractive index than the core part around the perimeter of the core part.

Abstract: An easily producible optical fiber preform which is drawn to an optical fiber having a core containing a sufficient concentration of alkali metal is provided. An optical fiber preform 10 is composed of silica-based glass and includes a core portion 20 and a cladding portion 30. The core portion 20 includes a first core portion 21 including a central axis and a second core portion 22 disposed on the perimeter of the first core portion 21. The cladding portion 30 includes a first cladding portion 31 disposed on the perimeter of the second core portion 22 and a second cladding portion 32 disposed on the perimeter of the first cladding portion 31. The core portion 20 contains an alkali metal at an average concentration of 5 atomic ppm or more. The concentration of the OH group in the perimeter portion of the first cladding portion 31 is 200 mol ppm or more.

Abstract: An optical fiber having excellent strength that can be manufactured at low cost, as well as a method for making such optical fiber, is provided. An optical fiber 1 is a silica-based optical fiber comprising a core 11, an optical cladding 12 surrounding the core & 11, and a jacketing region 13 surrounding the optical cladding 12 and having a uniform composition throughout from the internal circumference to the outer circumference. A compressive strained layer having a residual compressive stress is provided at the outermost circumference of the jacketing region 13.

Abstract: An optical fiber includes a core section and a cladding section. A k value expressed by k=4Aeff/(?MFD2) is 1.08 or larger, Aeff being an effective area and MFD being a mode field diameter, at a wavelength of 1550 nm, a chromatic dispersion is in a range from +19.0 ps/nm/km to +21.9 ps/nm/km, and MFD is in a range from 10.3 ?m to 13.0 ?m. The inequality, r1<r2<r3, is established, R=r3/r2 is larger than 1.0 and equal to or smaller than 5.4, and a relative refractive index difference ?12 of the maximum value N2 with respect to the minimum value N1 is 0.05% or higher, r1 and r2 being radial positions respectively with minimum and maximum value N1 and N2 of a refractive index in the core section and r3 being a radius of the core section.

Abstract: A method for making a high quality optical fiber preform includes: thermally defusing the alkali metal element into the inner side of a silica glass pipe by heating the glass pipe from the outside by a heat source while vapors of alkali metal salt generated by heating an alkali metal salt is supplied to the inside of the glass pipe from an end thereof; collapsing the glass pipe for forming a core rod; and adding a cladding part around the circumference of the core rod. At the start of the thermal diffusion, the alkali metal salt is heated at a temperature for making the vapor pressure of the alkali metal salt to be 0.1 kPa or less, and thereafter the alkali metal salt is heated up to a temperature for making the vapor pressure of the alkali metal salt to be larger than 0.1 kPa.

Abstract: The device uses a dispensing probe; a dispensing probe drive mechanism having at least one rotation drive shaft as a horizontal drive mechanism for the dispensing probe, a positioning member with a portion, which is contacted by the dispensing probe during positioning, is formed in a circular shape; a contact detection mechanism for detecting contact between the dispensing probe and the positioning member, and a control unit. The control unit drive-controls only one drive shaft into contact with the circular portion of the positioning member, and then drive-controls only one drive shaft other than the previously drive-controlled shaft into contact with the circular portion of the positioning member, and then calculates position information on a center point at a desired position where the dispensing probe is to be positioned, on the basis of position information on each point at which the contact has been detected, or the like.

Abstract: An optical fiber having excellent strength that can be manufactured at low cost, as well as a method for making such optical fiber, is provided. An optical fiber 1 is a silica-based optical fiber comprising a core 11, an optical cladding 12 surrounding the core 11, and a jacketing region 13 surrounding the optical cladding 12 and having a uniform composition throughout from the internal circumference to the outer circumference. A compressive strained layer having a residual compressive stress is provided at the outermost circumference of the jacketing region 13.

Abstract: The invention relates to an optical fiber employable in an optical communication system using Raman amplification and adapted to improve OSNR and suppress bending loss at the same time, and the like. The optical fiber is a silica-based optical fiber having a depressed refractive index profile constituted by at least a core, an inner cladding having a low refractive index, and an outer cladding, an effective area Aeff of 110 ?m2 or more at the wavelength of 1550 nm, and a fiber cutoff wavelength ?c of 1.3 ?m or more but 1.53 ?m or less. The depressed refractive index profile is designed such that the ratio Ra(=2b/2a) of the diameter of the inner cladding to the diameter of the core is 2.5 or more but 3.5 or less and that the relative refractive index difference ?? of the inner cladding with respect to the outer cladding is at least the relative refractive index difference ??min where the bending loss at the wavelength for use is minimized but not exceeding (??min+0.06) %.

Abstract: There is provided a semiconductor device having a reduced number of external terminals allocated for address input to receive access from outside, while realizing a high-speed response to an access from outside. The semiconductor device employs, in order to allow other external devices to directly access resources it possesses in its own address space, in an external interface circuit, external terminals which input a part of the address signal required for access from outside, a supplementary register which supplements the upper portion of address information that has been input from the external terminals, a mode register accessible from outside, and an address control circuit which generates an address signal to access the address space in a form based on information input from the external terminals, required supplementary information, and mode information of the mode register.

Abstract: A reaction solution is mixed in a short period of time with excellent stirring efficiency. During the stirring of the reaction solution, a rotation motor drives a stirring rod and a vertical motor moves the stirring rod in a vertically reciprocating manner in the reaction solution.

Abstract: There is provided a semiconductor device having a reduced number of external terminals allocated for address input to receive access from outside, while realizing a high-speed response to an access from outside. The semiconductor device employs, in order to allow other external devices to directly access resources it possesses in its own address space, in an external interface circuit, external terminals which input a part of the address signal required for access from outside, a supplementary register which supplements the upper portion of address information that has been input from the external terminals, a mode register accessible from outside, and an address control circuit which generates an address signal to access the address space in a form based on information input from the external terminals, required supplementary information, and mode information of the mode register.

Abstract: [Problem] An object of the present invention is to provide a novel anticancer drug which is useful for treating prostate cancer accompanying androgen receptor mutation [Means for Solution] The present inventors conducted thorough research on mutant androgen-related diseases for which the traditional anti-androgen drugs become ineffective. As a result, they found that the compound, which is an active ingredient of the pharmaceutical composition of the present invention, exhibits an inhibitory action against transcriptional activation in a human mutant androgen receptor (AR), and has an excellent antitumor action in a human prostate cancer-bearing mouse, thereby completing the present invention. Accordingly, the compound, which is an active ingredient of the pharmaceutical composition of the present invention, is useful for a series of androgen receptor-related diseases including prostate cancer.

Abstract: An optical fiber includes a core section and a cladding section. A k value expressed by k=4Aeff/(?MFD2) is 1.08 or larger, Aeff being an effective area and MFD being a mode field diameter, at a wavelength of 1550 nm, a chromatic dispersion is in a range from +19.0 ps/nm/km to +21.9 ps/nm/km, and MFD is in a range from 10.3 ?m to 13.0 ?m. The inequality, r1<r2<r3, is established, R=r3/r2 is larger than 1.0 and equal to or smaller than 5.4, and a relative refractive index difference ?12 of the maximum value N2 with respect to the minimum value N1 is 0.05% or higher, r1 and r2 being radial positions respectively with minimum and maximum value N1 and N2 of a refractive index in the core section and r3 being a radius of the core section.

Abstract: A fiber optic device outputs, at high conversion efficiency, an idler lightwave having a wavelength ?2 different from the wavelength of a signal lightwave by converting the signal lightwave having an optional wavelength ?1 in a wide wavelength band. The fiber optic device comprises a wavelength tunable pump light source for outputting a pump lightwave having a wavelength of 2×(?1?1+?2?1)?1; a optical coupler for coupling and outputting the pump lightwave and the signal lightwave; and an optical fiber having a length of 450 m or less, the zero-dispersion wavelength thereof being in the wide wavelength band, the dispersion slope thereof at the zero-dispersion wavelength being +0.01 ps/nm2/km or more and +0.045 ps/nm2/km or less, wherein the optical fiber allows propagation of the signal lightwave and the pump lightwave output from the optical coupler, and generates an idler lightwave by means of the nonlinear optical phenomenon that occurs during such propagation.

Abstract: There is provided a semiconductor device having a reduced number of external terminals allocated for address input to receive access from outside, while realizing a high-speed response to an access from outside. The semiconductor device employs, in order to allow other external devices to directly access resources it possesses in its own address space, in an external interface circuit, external terminals which input a part of the address signal required for access from outside, a supplementary register which supplements the upper portion of address information that has been input from the external terminals, a mode register accessible from outside, and an address control circuit which generates an address signal to access the address space in a form based on information input from the external terminals, required supplementary information, and mode information of the mode register.

Abstract: Highly accurate measurement of chromatic dispersions of a device under test that is an optical component is enabled with a simple structure comprising: propagating pump light having a wavelength ?pump and probe light having a wavelength ?probe through the device; calculating the generation efficiency of the idler light with respect to the wavelength ?pump by measuring the power of idler light having a wavelength ?idler output from the device according to four-wave mixing generated in the device; seeking the frequency difference or wavelength difference between the pump light and the probe light that makes an extremum of generation efficiency of the idler light; calculating phase mismatch among the pump light wavelength having such frequency difference or wavelength difference, the probe light wavelength, and the idler light wavelength; and on the basis of such calculation results, calculating the chromatic dispersion of the device at the wavelength ?pump.

Abstract: A method for the manufacture of an optical fiber preform for producing a low attenuation optical fiber with high yield, comprising preparing a core rod and adding a cladding region. At the step of preparing a core rod, the core rod is produced including a first core region with Cl density of less than 600 atm-ppm, a second core region with Cl density of less than 600 atm-ppm around the first core region, and a third core region with Cl density of 3000 atm-ppm or more around the second core region. An alkali metal is selectively added to the first core region among the first, second, and third core regions. A cladding region is formed around the core rod by heating at a temperature of 1200° C. or higher for 7 hours or less.

Abstract: The chromatic dispersion of an optical component is measured with high accuracy using a simple set-up, which includes a pump light source, a probe light source, and a measuring means. Pump light having a wavelength ?pump and probe light having a wavelength ?probe is propagated through an optical component, with the wavelength ?probe being apart from the wavelength ?pump by a given frequency. The generation efficiency of the idler light with respect to the wavelength ?pump is calculated by measuring the power of idler light having a wavelength ?idler output from the optical component, and by seeking the pump light wavelength for making the generation efficiency a local extreme value, the chromatic dispersion of the optical component is calculated from the result of calculation of phase mismatch among the pump light wavelength having such wavelength as sought, the corresponding probe light wavelength, and the corresponding the idler light wavelength.

Abstract: There is provided a method for producing an optical fiber having low attenuation, the optical fiber including a core that contains an alkali metal element. An optical fiber preform that includes a core part and a cladding part is drawn with a drawing apparatus to form an optical fiber, the core part having an average concentration of an alkali metal element of 5 atomic ppm or more. During the drawing, the time the temperature of glass is maintained at 1500° C. or higher is 110 minutes or less. The drawing speed is preferably 1200 m/min or more and more preferably 1500 m/min to 2300 m/min. The optical fiber preform preferably has a diameter of 70 mm to 170 mm and more preferably 90 mm to 150 mm.