摘要:
A drawing method for a bare optical fiber, comprises the steps of: melting an optical fiber preform using a heating device and drawing the bare optical fiber; and naturally cooling down the bare optical fiber or forcibly cooling down the bare optical fiber by a cooling device after the heating and melting step, wherein a temperature history during the drawing the optical fiber preform to obtain the bare optical fiber in the heating device satisfies a relational expression: T≦−0.01X+12 where a time period when the heated and molten portion of the optical fiber preform heated and molten by the heating device reaches 1800° C. or higher is T (min) and a OH group concentration in a cladding layer of the optical fiber preform is X (wtppm).
摘要:
An optical fiber twisting apparatus that prevents line distortion in an optical fiber undergoing a drawing process and provides a consistent coating on a bare optical fiber. This optical fiber twisting apparatus includes a twist roller apparatus that having a twist roller that, by imparting a twist to an optical fiber, imparts a twist to a molten portion of an optical fiber preform positioned on an upstream side of the optical fiber, and a support portion that supports the twist roller. The accuracy of the outer circumference of the twist roller when the twist roller is forming a part of the twist roller apparatus is 15 μm or less.
摘要:
A drawing method for a bare optical fiber, comprises the steps of: melting an optical fiber preform using a heating device and drawing the bare optical fiber; and naturally cooling down the bare optical fiber or forcibly cooling down the bare optical fiber by a cooling device after the heating and melting step, wherein a temperature history during the drawing the optical fiber preform to obtain the bare optical fiber in the heating device satisfies a relational expression: T≦−0.01X+12 where a time period when the heated and molten portion of the optical fiber preform heated and molten by the heating device reaches 1800° C. or higher is T (min) and a OH group concentration in a cladding layer of the optical fiber preform is X (wtppm).
摘要:
An optical fiber twisting apparatus that prevents line distortion in an optical fiber undergoing a drawing process and provides a consistent coating on a bare optical fiber. This optical fiber twisting apparatus includes a twist roller apparatus that having a twist roller that, by imparting a twist to an optical fiber, imparts a twist to a molten portion of an optical fiber preform positioned on an upstream side of the optical fiber, and a support portion that supports the twist roller. The accuracy of the outer circumference of the twist roller when the twist roller is forming a part of the twist roller apparatus is 15 μm or less.
摘要:
An optical fiber twisting apparatus that prevents line distortion in an optical fiber undergoing a drawing process and provides a consistent coating on a bare optical fiber. This optical fiber twisting apparatus includes a twist roller apparatus that having a twist roller that, by imparting a twist to an optical fiber, imparts a twist to a molten portion of an optical fiber preform positioned on an upstream side of the optical fiber, and a support portion that supports the twist roller. The accuracy of the outer circumference of the twist roller when the twist roller is forming a part of the twist roller apparatus is 15 μm or less.
摘要:
An optical fiber twisting apparatus that prevents line distortion in an optical fiber undergoing a drawing process and provides a consistent coating on a bare optical fiber. This optical fiber twisting apparatus includes a twist roller apparatus that having a twist roller that, by imparting a twist to an optical fiber, imparts a twist to a molten portion of an optical fiber preform positioned on an upstream side of the optical fiber, and a support portion that supports the twist roller. The accuracy of the outer circumference of the twist roller when the twist roller is forming a part of the twist roller apparatus is 15 μm or less.
摘要:
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.
摘要:
A magnetic material of an embodiment includes: first magnetic particles that contain at least one magnetic metal selected from the group including Fe, Co, and Ni, are 1 μm or greater in particle size, and are 5 to 50 μm in average particle size; second magnetic particles that contain at least one magnetic metal selected from the group including Fe, Co, and Ni, are smaller than 1 μm in particle size, and are 5 to 50 nm in average particle size; and an intermediate phase that exists between the first magnetic particles and the second magnetic particles.
摘要:
A radiowave absorber of an embodiment includes: core-shell particles each including: a core portion that contains at least one magnetic metal element selected from a first group including Fe, Co, and Ni, and at least one metal element selected from a second group including Mg, Al, Si, Ca, Zr, Ti, Hf, Zn, Mn, rare-earth elements, Ba, and Sr; and a shell layer that coats at least part of the core portion, and includes an oxide layer containing at least one metal element selected from the second group and contained in the core portion; and a binding layer that binds the core-shell particles, and has a higher resistance than the resistance of the core-shell particles. The volume filling rate of the core-shell particles in the radiowave absorber is not lower than 10% and not higher than 55%.
摘要:
According to one embodiment, there is provided a nanoparticle composite material, including nanoparticle aggregates in a shape having an average height of 20 nm or more and 2 μm or less and having an average aspect ratio of 5 or more, the nanoparticle aggregates including metal nanoparticles having an average diameter of 1 nm or more and 20 nm or less and containing at least one magnetic metals selected from the group consisting of Fe, Co and Ni and binder existing between the nanoparticle aggregates.