Single-mode optical fiber and optical system

Abstract

This optical fiber comprises a central core, an intermediate cladding, a trench, and optical cladding. The central core has a refractive index difference ”n 1 relative to the optical cladding in the range 2.6×10 -3 to 3.5×10 -3 . The trench has a radius r 3 that is less than 24 µm. The refractive index difference ”n 3 of the trench relative to the optical cladding is in the range -15.0×10 -3 to -4.5×10 -3 at 633 nm. The volume V 13 of the trench, defined as follows: V 13 = 2 �¢ À . ˆ« r 2 r 3 ”n r �¢ rdr is in the range 170 %.µm 2 to 830 %.µm 2 . This fiber has an effective area greater than or equal to 150 µm 2 at a wavelength of 1550 nm and lower bending losses. Use in particular in long-haul terrestrial systems or undersea systems with or without repeaters.

Description

Technical field [0001] The present invention relates to the field of optical fiber transmission, and more specifically, to an optical fiber with an increased effective area but no increase in bending loss and a corresponding optical system. Background technique [0002] Generally speaking, in the field of optical fiber, the concept of effective area is introduced in order to calculate nonlinear effects. The effective area generally corresponds to the usable section of the fiber defined by the mode distribution of the field propagation in the fiber. [0003] By way of non-limiting example, the effective area Aeff is defined as follows: [0004] Aeff = 2 π ( ∫ 0 ∞ | F ( r ) | 2 rdr ) 2 ∫ 0 ∞ | F ( r ) | 4 rdr . [0005] Wherein, F(r) is the mode distribution of the fundamental mode LP01 at the radius r, that is, the mode distribution at the polar distance r in the polar coordinate system with the cr...

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Problems solved by technology

[0020] Therefore, the question that arises is: how to increase the effective area Aeff to more than 150 μm 2 , without substantially increasing manufacturing costs and without compromising performance in terms of bend loss

[0040] Thus, the prior art described above does not present a satisfactory compromise regarding distribution characteristics and / or propagation characteristics such that a fiber having a large effective area and relatively low macrobend loss and Slotted Fiber with Microbend Loss

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