Abstract: An optical fiber and an optical fiber device, which can suppress generation of the stimulated Brillouin scattering while maintaining large nonlinearity. The fiber includes a central core which is made of SiO2 as a main component and contains Al2O3 at concentration of 15 wt % or more. The fiber is allowed to propagate only a fundamental mode and has an absolute value of chromatic dispersion of 5 ps/nm/km or less at a predetermined wavelength. The device includes the fiber having the above composition. The fiber guides first light and second light having different wavelengths to propagate therethrough such that the first light and the second light interact with each other by a nonlinear optical phenomenon during the propagation, thus causing the fiber to output the first light or the second light modulated by the nonlinear optical phenomenon or third light newly produced by the nonlinear optical phenomenon and having a different wavelength.

Abstract: A core rod is inserted into a cladding pipe, moisture in a space between the core rod and the cladding pipe is removed, and an optical fiber is drawn while the space is connected to a dry-gas atmosphere and/or being decompressed and while the core rod and the cladding pipe are being unified with each other. Alternatively, the core rod is inserted into the cladding pipe, and an optical fiber is drawn from one end while moisture on the surface of the core rod and the internal surface of the cladding pipe is being removed. Accordingly, a high quality optical fiber is manufactured with good productivity.

Abstract: There is disclosed an optical fiber wherein an absolute value of the fourth order dispersion ?4 of fourth derivative ?4 of propagation constant ? with respect to angular frequency ? at a mean zero dispersion wavelength ?0 in an overall length is not more than 5×10?56 s4/m and wherein a fluctuation of a zero dispersion wavelength along a longitudinal direction is not more than ±0.6 nm.

Abstract: Compounds useful as GnRH receptor antagonists are provided. The present inventors have further examined propane-1,3-dione derivatives and confirmed as a result that a propane-1,3-dione having 2-(1,3-dihydro-2H-benzimidazol-2-ylidene), or a compound which has benzene or thiophene ring substituted with a group derived from 1-hydroxymethyl, shows excellent availability, in addition to its excellent GnRH receptor antagonism, thereby accomplishing the invention. Since the compound of the invention shows excellent availability, in addition to its strong GnRH receptor antagonism, it can be expected that it exerts superior drug effect in the living body, and it is useful for the treatment of sex hormone dependent diseases such as prostate cancer, breast cancer, endometriosis, uterine leiomyoma, benign prostatic hypertrophy and the like.

Abstract: Provided is a hollow-body cavity inspection device for inspecting a hollow-body cavity filled with a limited-wavelength transparent medium.

Abstract: The present invention provides a luminescence measuring method that can be accurately and quickly carried out while inhibiting a possible background associated with viable bacteria adhering to a nozzle or Adenosine Tri Phosphate remaining in the nozzle, and an apparatus for the method. The present invention uses a washing apparatus characterized by including a nozzle, a lysys solution, a luminescence reagent solution, and a detection section, as well as a relevant washing method and a relevant luminescence measuring method. To remove viable bacteria adhering to the nozzle, the nozzle is immersed in the lysys solution and then in the luminescence reagent solution. The detection section monitors luminescence occurring during a washing process.

Abstract: A light source unit and a spectrum analyzer are provided in which the influence of interference can be reduced under conditions where light is separated into spectral components. A spectrum analyzer 1 is equipped with a light source unit 2 for irradiating light onto sample A, a detector unit 3 for detecting the light reflected, scattered, or transmitted from the sample A, and a sample stage 4 on which a sample A is placed. A wide band light source 20 generates wide band light P1 such as supercontinuum light (SC light). Also, the light source unit 2 has an interference suppressing means for suppressing the interference of each wavelength component of the wide band light P1.

Abstract: The present invention relates to an optical fiber for light pulse expansion in which the ratio (?3,?2) of the third derivative ?3 to the second derivative ?2 is negative, the absolute value thereof is large, and the absolute value of the second derivative ?2 is also large. Such an optical fiber comprises at least a central core portion having a maximum refractive index N1 and an outer diameter 2a , a depressed portion, provided on the outer periphery of the central core portion, having a minimum refractive index N2 and an outer diameter 2b, and a cladding portion, provided on the outer periphery of the depressed portion, having a maximum refractive index N3. The respective maximum refractive indices of the central core portion, the depressed portion and the cladding portion satisfy the relationship “N1>N3>N2”. The relative refractive index difference ?1 of the central core portion with respect to the cladding portion is larger than 1.

Abstract: A container for an optical fiber coil and an optical fiber module including the container is provided, wherein an excess length portion of a pigtail fiber is accommodated in the container and the remaining portion can be drawn out from the container. The container includes a first part for accommodating a coil having a functional optical fiber, and a second part disposed on an outer periphery side of the first part and windingly accommodating a pigtail fiber that is optically connected to the functional optical fiber. The second part has a gap that extends over the entirety of the outer periphery, and communicates with the exterior. The optical fiber module includes the container, the coil having the functional optical fiber accommodated in the first part of the container, and the pigtail fiber that is optically connected to the functional fiber and that has a portion windingly accommodated in the second part.

Abstract: Methods of manufacturing an optical fiber preform and an optical fiber, and an optical fiber formed by this method of manufacturing an optical fiber are provided, the optical fiber preform having a desired refractive index profile and being capable of suppressing an increase in loss due to the absorption by OH groups. A pipe is formed by an inside vapor phase deposition method such that glass layer to be formed into a core and a glass layer to be formed into a part of a cladding pipe are deposited in a starting pipe, the glass layers each containing at least one of fluorine, germanium, phosphorous, and chlorine, the starting pipe being made of a silica glass having an outside diameter in the range of 20 to 150 mm and a wall thickness in the range of 2 to 8 mm. The pipe thus formed is collapsed to form a glass rod in which the concentration of hydroxyl groups is 10 weight ppm or less in a region from the surface of the glass rod to a depth of 1 mm therefrom.

Abstract: A core rod is inserted into a cladding pipe, moisture in a space between the core rod and the cladding pipe is removed, and an optical fiber is drawn while the space is connected to a dry-gas atmosphere and/or being decompressed and while the core rod and the cladding pipe are being unified with each other. Alternatively, the core rod is inserted into the cladding pipe, and an optical fiber is drawn from one end while moisture on the surface of the core rod and the internal surface of the cladding pipe is being removed. Accordingly, a high quality optical fiber is manufactured with good productivity.

Abstract: An optical fiber and an optical fiber device, which can suppress generation of the stimulated Brillouin scattering while maintaining large nonlinearity. The fiber includes a central core which is made of SiO2 as a main component and contains Al2O3 at concentration of 15 wt % or more. The fiber is allowed to propagate only a fundamental mode and has an absolute value of chromatic dispersion of 5 ps/nm/km or less at a predetermined wavelength. The device includes the fiber having the above composition. The fiber guides first light and second light having different wavelengths to propagate therethrough such that the first light and the second light interact with each other by a nonlinear optical phenomenon during the propagation, thus causing the fiber to output the first light or the second light modulated by the nonlinear optical phenomenon or third light newly produced by the nonlinear optical phenomenon and having a different wavelength.

Abstract: An optical fiber capable of effectively suppressing stimulated Brillouin scattering, and an optical module including the fiber are provided. The fiber includes a core region, and a cladding region having a refractive index lower than that of the core region and an acoustic velocity higher than that of the core region. An effective area of the fiber is 5?2 or less at at least one light wavelength ?. The ratio ?A/?O of an acoustic relative refractive index ratio ?A and an optical relative refractive index ratio ?O is 25 or more. The optical module includes the optical fiber, a light source that outputs first light having a wavelength ?1, and a multiplexer that receives the first light and second light having a wavelength ?2 and that multiplexes and couples the first light and the second light to the optical fiber.

Abstract: Provided is a method of manufacturing an optical fiber preform from which an optical fiber having the desired characteristics can easily be produced.

Abstract: Glass can be synthesized and deposited at a high rate by the inside CVD method using a plasma burner in a manner such that unconsolidated portions or bubbles are little generated. The method includes a step of depositing a glass film on the inner wall surface of a starting pipe. In a first aspect, temperature the pipe is controlled not to exceed (1800+100×d)° C., a temperature of (1100+100×d)° C. or higher being continued for 20 seconds or more at each point of the pipe, where d (mm) represents the wall thickness of the pipe. In a second aspect, the burner includes at least two inlets and has an inner diameter of 80 mm or more, and the deposition step is performed in the relationship, 150 mm/s<(Total flow rate of the gases introduced into the burner)/(Sectional area of the burner)<600 mm/s.

Abstract: An optical device and wavelength conversion method can selectively perform wavelength conversion of a probe lightwave. An optical fiber is suitable for them. The device 1 comprises (a) a pump light source 12 for outputting a pump lightwave having a wavelength of ?pump and (b) an optical fiber 11 that guides the pump lightwave and a probe lightwave having a wavelength of ?probe and generates through a nonlinear optical phenomenon an idler lightwave having a newly produced wavelength of ?idler that is in accordance with the wavelength ?probe. The wavelength ?probe dependence of the efficiency of the wavelength conversion has a main band including the wavelength ?pump and a subband distinct from the main band. The probe lightwave included in the subband is guided in the optical fiber 11 to generate in it the idler lightwave having the wavelength ?idler that is in accordance with the wavelength ?probe.

Abstract: The present invention relates to an optical fiber which has a structure for further increasing an FOM (=|dispersion|/loss) and which can be applied to a dispersion compensation module. The optical fiber is mainly composed of silica glass and has a core region including a center of an optical axis, a depressed region surrounding the core region, a ring region surrounding the depressed region, and a cladding region surrounding the ring region and doped with F. As compared with the refractive index of pure silica glass, a relative refractive index difference of the core region is 3% or more but 4% or less, a relative refractive index difference of the depressed region is ?1% or more but ?0.5% or less, a relative refractive index difference of the ring region is 0.01% or more but 0.24% or less, and a relative refractive index difference of the cladding region is ?0.3% or more but ?0.1% or less. The FOM at the wavelength of 1550 nm is 250 ps/nm/dB or more.

Abstract: The present invention relates to an optical fiber which has a structure for further increasing an FOM (=|dispersion|/loss) and which can be applied to a dispersion compensation module. The optical fiber is mainly composed of silica glass and has a core region including a center of an optical axis, a depressed region surrounding the core region, a ring region surrounding the depressed region, and a cladding region surrounding the ring region and doped with F. As compared with the refractive index of pure silica glass, a relative refractive index difference of the core region is 3% or more but 4% or less, a relative refractive index difference of the depressed region is ?1% or more but ?0.5% or less, a relative refractive index difference of the ring region is 0.01% or more but 0.24% or less, and a relative refractive index difference of the cladding region is ?0.3% or more but ?0.1% or less. The FOM at the wavelength of 1550 nm is 250 ps/nm/dB or more.

Abstract: A method and apparatus capable of suppressing fluctuation in shrinkage of a silica glass pipe such that an optical fiber preform uniform in the longitudinal direction can be produced are provided. In the step of depositing a glass layer in the silica glass pipe, at least the amount of the exhaust gas or buffering gas is feedback-controlled, and at least other one of them is pattern-controlled according to a flow rate pattern corresponding to heating positions on the silica glass pipe. The apparatus includes two or more in total of an exhaust portion and a buffering gas inlet portion, a heat source, a position detecting means for detecting a heating position, a first control means for controlling at least the amount of the exhaust gas or buffering gas according a flow rate pattern corresponding to heating positions, and second control means for feedback-controlling at least other one of them.

Abstract: An optical fiber capable of effectively suppressing stimulated Brillouin scattering, and an optical module including the fiber are provided. The fiber includes a core region, and a cladding region having a refractive index lower than that of the core region and an acoustic velocity higher than that of the core region. An effective area of the fiber is 5?2 or less at at least one light wavelength ?. The ratio ?A/?O of an acoustic relative refractive index ratio ?A and an optical relative refractive index ratio ?O is 25 or more. The optical module includes the optical fiber, a light source that outputs first light having a wavelength ?1, and a multiplexer that receives the first light and second light having a wavelength ?2 and that multiplexes and couples the first light and the second light to the optical fiber.