摘要:
A multimode optical fiber includes a central core, an inner cladding, a buried trench, and an outer cladding (e.g., an outer optical cladding). Typically, the optical fiber's central core is a glass-based central core having an alpha-index profile (i.e., a graded-index profile), an outer radius r1, and a maximum refractive index difference Δn1 with respect to the outer cladding. The central core's alpha-index profile has a minimum refractive index at the central core's outer radius r1 that corresponds to a refractive index difference Δnend with respect to the outer cladding. The inner cladding has an outer radius r2, a width w2, and a refractive index difference Δn2 with respect to the outer cladding. The buried trench has an outer radius rext, a width w3, and a refractive index difference Δn3 with respect to the outer cladding. The multimode optical fiber typically has reduced bending losses, a high bandwidth at wavelengths of both 850 nanometers and 1300 nanometers, and a reduced cladding effect.
摘要:
An optical fiber having a core and an outer cladding, the core including from its center outward a central core having a radius and a refractive index difference with respect to the outer cladding, and a depressed inner cladding. The depressed inner cladding includes at least a first portion having a radius and a refractive index difference with respect to the outer cladding, the first portion preferably being adjacent to the central core, and a second portion adjacent to the first portion constituting a depressed trench having a radius, and a refractive index difference with respect to the outer cladding. The first portion of the inner cladding has a refractive index below the refractive index of the outer cladding, and the depressed trench has a refractive index that is lower than the refractive index of the first portion of the depressed inner cladding. The outer radius of the depressed inner cladding of the optical fiber is between 28 μm and 40 μm, the LP01 mode leakage losses at a wavelength of 1550 nm are less than 0.01 dB/km and the cable cut-off wavelength is less than 1530 nm.
摘要:
A single-mode optical fiber includes a central core, an intermediate cladding, a depressed trench, and an external optical cladding. The central core has a radius r1 and a positive refractive index difference Δn1 with the optical cladding. The intermediate cladding has a radius r2 and a refractive index difference Δn2 with the optical cladding, wherein Δn2 is less than Δn1. The depressed trench has a radius r3 and a negative index difference Δn3 with the optical cladding. At a wavelength of 1310 nanometers, the optical fiber has a mode field diameter (MFD) between 8.6 microns and 9.5 microns and, at a wavelength of 1550 nanometers, the optical fiber has bending losses less than about 0.25×10−3 dB/turn for a radius of curvature of 15 millimeters. At a wavelength of 1260 nanometers, attenuation of the LP11 mode to 19.3 dB is achieved over less than 90 meters of fiber.
摘要:
The present invention embraces an optical fiber that includes a central core having an alpha-index profile with respect to an outer cladding. The optical fiber also includes an inner cladding, a depressed trench, and an outer cladding. Typically, the alpha-index profile of the central core is interrupted at a point having a positive refractive index difference with respect to the outer cladding. The optical fiber achieves reduced bending losses and a high bandwidth with a reduced cladding effect for high-data-rate applications.
摘要:
A multimode optical fiber includes a central core surrounded by an outer cladding. The central core has a graded-index profile with respect to the outer cladding and an outer radius r1 of between about 22 microns and 28 microns. The optical fiber also includes an inner cladding positioned between the central core and the outer cladding, and a depressed trench positioned between the inner cladding and the outer cladding. The multimode optical fiber exhibits reduced bending losses.
摘要:
The present invention embraces an optical fiber that includes a central core having an alpha refractive index profile with respect to an outer cladding. The optical fiber also includes an inner cladding, a depressed trench, and an outer cladding. The optical fiber achieves reduced bending losses and a high bandwidth with a reduced cladding effect for high-data-rate applications.
摘要:
A multimode optical fiber includes a central core having a graded-index profile with a delta value of about 1.9 percent or greater. The graded-index core profile has at least two different alpha parameter values along the core radius, namely a first value in an inner zone of the central core and a second value in an outer zone of the central core. The second alpha parameter value is typically less than the first alpha parameter value. The graded-index core profile and its first derivative are typically substantially continuous over the width of the graded-index core.
摘要:
Disclosed is an optical transmission fiber having reduced bending and microbending losses that is commercially usable in FTTH or FTTC transmission systems.
摘要:
An optical transmission fiber comprises a central core having an index difference Δn1 with an outer optical cladding; a first inner cladding having an index difference Δn2 with the outer cladding; and a second buried inner cladding having an index difference Δn3 with the outer cladding of less than −3.10−3. The second buried inner cladding moreover contains Germanium in a weight concentration of between 0.5% and 7%.The fiber shows reduced bending and microbending losses whilst exhibiting the optical performances of a standard single-mode fiber (SSMF).
摘要:
A multimode optical fiber includes a central core, an inner cladding, a buried trench, and an outer cladding (e.g., an outer optical cladding). Typically, the optical fiber's central core is a glass-based central core having an alpha-index profile (i.e., a graded-index profile), an outer radius r1, and a maximum refractive index difference Δn1 with respect to the outer cladding. The central core's alpha-index profile has a minimum refractive index at the central core's outer radius r1 that corresponds to a refractive index difference Δnend with respect to the outer cladding. The inner cladding has an outer radius r2, a width w2, and a refractive index difference Δn2 with respect to the outer cladding. The buried trench has an outer radius rext, a width w3, and a refractive index difference Δn3 with respect to the outer cladding. The multimode optical fiber typically has reduced bending losses, a high bandwidth at wavelengths of both 850 nanometers and 1300 nanometers, and a reduced cladding effect.