摘要:
An optical fiber comprising: (i) a glass core (20) extending from a centerline and including a central core region (22) with an alpha value of less than 2, a first annular core region (24) surrounding the central core region (22), and a second annular core region (26) surrounding the first annular core region (24), wherein the second annular core region (26) has a higher maximum relative refractive index percent Δ26MAX than that maximum relative refractive index percent Δ24MAX of the first annular core region (24); and (ii) a glass cladding (30) surrounding and in contact with the core (20), the cladding comprising: (a) a first annular cladding region (32) extending from a radius R32 to a radius R34, (b) a second annular cladding region (34) extending from the radius R34 to a radius R36, (c) a third annular cladding region (36) surrounding the second annular region (34) and extending from the radius R34 to an outermost glass radius R36; wherein the core (20) comprises a maximum relative refractive index percent, ΔCMAX; wherein said first annular cladding region (32) comprises relative refractive index percent Δ32(r) % the second annular cladding region (34) comprises a minimum relative refractive index percent, Δ34 MIFN, wherein ΔCMAX>Δ32MAX>Δ34MIN, and Δ34MIN
摘要:
An embodiment of a sensor fiber includes: at least two fiber sections with a plurality of holes; and at least one other fiber section situated between said at least two fiber sections, wherein the at least one other fiber sections being without the plurality of holes.
摘要:
An optical fiber comprising: (i) a glass core (20) extending from a centerline and including a central core region (22) with an alpha value of less than 2, a first annular core region (24)surrounding the central core region (22), and a second annular core region (26) surrounding the first annular core region (24), wherein the second annular core region (26) has a higher maximum relative refractive index percent Δ26MAX than that maximum relative refractive index percent Δ24MAX of the first annular core region (24); and (ii) a glass cladding (30) surrounding and in contact with the core (20), the cladding comprising: (a) a first annular cladding region (32) extending from a radius RC3 to a radius R32, (b) a second annular cladding region (34) extending from the radius R32 to a radius R34, (c) a third annular cladding region (36) surrounding the second annular region (34) and extending from the radius R34 to an outermost glass radius R36; wherein the core (20) comprises a maximum relative refractive index percent ΔCMAX; wherein said first annular cladding region (32) comprises relative refractive index percent Δ32(r) % the second annular cladding region (34) comprises a minimum relative refractive index percent, Δ34 MIN, wherein ΔCMAX>Δ32MAX>Δ34MIN, and Δ34MIN
摘要:
An optical fiber includes a silica-based glass portion having an outer diameter of less than about 120 μm. The glass portion comprises a core, an inner cladding and a low index ring. The core comprises an index of refraction n1, and a relative refractive index percent Δ1% relative to pure silica glass. The inner cladding surrounds the core and comprises an index of refraction n2, a radial thickness of less than about 40 μm and a relative refractive index percent Δ2% relative to pure silica glass, wherein Δ1%>Δ2% and the difference between Δ1% and Δ2% is greater than 0.1%. The low index ring surrounds the inner cladding and comprises boron and fluorine, a radial thickness of less than about 20 μm, an index of refraction n3 and a third relative refractive index percent Δ3% relative to pure silica glass, wherein Δ2%>Δ3% and Δ3% is less than −0.5%.
摘要:
A method for producing an optical fiber is provided. The method includes the steps of drawing an optical fiber from a heated glass source in a furnace and introducing index perturbations to the optical fiber via a plurality of perturbation sources arranged at a plurality of different azimuthal locations. The index perturbations are introduced synchronously at different locations along the axial length of the fiber by the plurality of perturbation sources in a generally helical pattern on the outside surface of the fiber in one embodiment. According to another embodiment, the index perturbations are introduced by the plurality of perturbation sources at different frequencies.
摘要:
A system for simultaneously determining strain and temperature characteristics of an object comprising: (i) at least one optical fiber having at least two Brillouin peaks; (ii) at least one connector securing the optical fiber to the object to be monitored; (iii) a laser positioned to provide laser light to said at least one optical fiber; (iv) a device measuring frequencies of said at least two Brillouin peaks, and determining frequency shifts of said at least two Brillouin peaks for said at least one optical fiber along the length of fiber; and (v) a system calculating strain and temperature characteristics along said fiber, based on the coefficients of strain and temperature as well as the measured Brillouin frequency shifts for said optical fiber along the length of said optical fiber.
摘要:
A large-mode-area (LMA) optical fiber (10) that operates as a single-mode optical fiber. The optical fiber includes a core region (20) surrounded by an inner cladding (32), which in turn is surrounded by an outer cladding (40). The inner cladding includes at least one up-doped ring region (32R1). The ring region is configured to form a large attenuation differential between the higher-order modes and the fundamental mode so only that the fundamental mode remains traveling in the optical fiber. If necessary, the optical fiber can include a bend (10B) having a select “resonant” bend diameter (DB) that increases the relative attenuation of the fundamental and higher-order modes. The optical fiber supports an effective mode field diameter (MFD) of up to 40 μm to 50 μm. As a result, detrimental non-linear effects are suppressed, which allows the optical fiber to carry substantially more optical power than conventional LMA optical fibers. The LMA optical fiber is thus eminently suited for a number of optical-fiber-based applications calling for high optical power, such as fiber lasers and pump sources for wavelength conversion.
摘要:
Generation of a cylindrically polarized light beam, and in particular, a hybrid-azimuthal-radial polarization beams, called HARP modes, generated from an input linearly polarized Gaussian beam using a spun optical waveguide device is taught. The HARP modes are comprised of hybrid-azimuthal polarization (HAP) and hybrid-radial polarization (HRP) superposition modes. These beams possess a non-zero local angular momentum density that is spatially varying and a zero total angular momentum.
摘要:
A detection system comprising: (i) an optical fiber, the optical fiber having (a) a length L≧1 km; (b) beat length between 10 m and 100 m; and (c) beat length uniformity over any distance of at least 100 m within the length L is characterized by standard deviation σ, where |σ|≦10 m; (ii) an OTDR coupled to the fiber and including (a) a radiation source providing pulsed radiation to the fiber, (b) a detection system capable of detecting radiation that is backscattered back through the fiber; and (iii) at least one polarizer situated between the fiber and the detector, such that the backscattered radiation passes through the polarizer before reaching the detector.
摘要:
Multimode optical fiber is disclosed herein having a core surrounded by first and second annular cladding regions. The second annular cladding region has a maximum relative refractive index that is at least 0.05% higher than the minimum relative refractive index of the first annular cladding region.