摘要:
A method includes a first step of joining a multimode fiber to a first end of an optical fiber being a specimen, allowing light to propagate from the multimode fiber to the specimen, measuring an intensity of light from a second end of the specimen, and determining a first power spectrum; a second step of joining the multimode fiber to a first end of a reference fiber having bending loss higher than that of the specimen, allowing light to propagate from the multimode fiber to the reference fiber, measuring an intensity of light from a second end of the reference fiber, and determining a second power spectrum; a third step of determining a difference spectrum by subtracting the second power spectrum from the first power spectrum; and a fourth step of determining a higher-order mode cutoff wavelength of the specimen on the basis of a shape of the difference spectrum.
摘要:
A method includes a first step of joining a multimode fiber to a first end of an optical fiber being a specimen, allowing light to propagate from the multimode fiber to the specimen, measuring an intensity of light from a second end of the specimen, and determining a first power spectrum; a second step of joining the multimode fiber to a first end of a reference fiber having bending loss higher than that of the specimen, allowing light to propagate from the multimode fiber to the reference fiber, measuring an intensity of light from a second end of the reference fiber, and determining a second power spectrum; a third step of determining a difference spectrum by subtracting the second power spectrum from the first power spectrum; and a fourth step of determining a higher-order mode cutoff wavelength of the specimen on the basis of a shape of the difference spectrum.
摘要:
The present invention relates to an analyzing apparatus and the like having a structure for enabling spectrometry and the like up to a longer frequency region while being excellent in practicality. The analyzing apparatus comprises a light source section and a light-detecting section. The light source section includes a seed light source emitting laser light, and a solid highly nonlinear optical fiber generating SC light in response to the input of the laser light, and thereby emitting the SC light as irradiation light to an object. The light-detecting section detects light to be detected from the object irradiated with the irradiation light. Here, the seed light source in the light source section emits pulsed light having a center wavelength within the range of 1.3 μm to 1.8 μm.
摘要:
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.
摘要:
An apparatus can heat a glass body with high efficiency, and a method incorporating the apparatus produces an optical fiber preform. The apparatus has (a) a heating element that has a nearly cylindrical shape and that heats a glass body inserted into the heating element and (b) an infrared reflector that is placed at a position next to each of the openings of the heating element, that surrounds the glass body together with the heating element, and that has an inner surface having a spectral emissivity of at most 0.70 in a wavelength range of 4 to 12 μm.
摘要:
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.
摘要:
An optical fiber and a broadband light source that can generate SC light having a broader bandwidth. A broadband light source 1 is equipped with a seed light source 11 and an optical fiber 12. The seed light source 11 outputs light having a central wavelength in the wavelength range of 1500 nm to 1650 nm. The optical fiber 12 outputs supercontinuum light a result of input of the light output from the seed light source. The optical fiber 12, which has a zero dispersion wavelength in the wavelength range of 1300 nm to 1500 nm and an effective area of 12 μm2 or less at the central wavelength, outputs supercontinuum light having a wavelength bandwidth expanded to 1000 nm or more.
摘要:
Provided is a hollow-body cavity inspection device for inspecting a hollow-body cavity filled with a limited-wavelength transparent medium. The hollow-body cavity inspection device is capable of multifunction in addition to acquisition of an image and comprises: (1) one or more light sources for emitting two or more inspection light beams of different characteristics; (2) a light transmitting member for transmitting the two or more inspection light beams to an inspection objective in a hollow-body cavity and transmitting the reflected/scattered light from the inspection objective to the outside of the hollow-body; and (3) an inspection data formation means for receiving the reflected/scattered light and forming inspection information therefrom, wherein the two or more inspection light beams include first inspection light having its main wavelength bandwidth at the transmittable wavelength band, and the inspection data formation means comprises a plurality of means for outputting inspection information differing according to each of the two or more inspection light beams.
摘要:
A method of manufacturing an optical fiber preform is provided, with which an increase of PMD and transmission loss of an optical fiber can be restrained. The method of manufacturing an optical fiber preform includes a process of heating a glass pipe and comprises the steps of (1) supporting the glass pipe at both ends thereof such that the longitudinal axis of the glass pipe becomes substantially horizontal and (2) heating the glass pipe with a heat source, wherein the bending moment at the supporting end of the glass pipe which is treated as a cantilever is 6 Nm or more, and the displacement of the heated region of the glass pipe in the heating process is equal to or less than 1.5 mm.
摘要:
In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.