Bell Communications Research, Inc.

Lucent Technologies Inc.

Virendra S Shah

William C Young

Lyn Curtis

Derek D Mahoney

James W Sulhoff

Atul Kumar Srivastava

Yan Sun

Liyan Zhang

A method of modeling erbium doped fiber (&ldquo;EDF&rdquo;) for use in erbium doped fiber amplifiers (&ldquo;EDFA&rdquo;). The EDF has a length and a fractional population density of erbium ions in an excited state. Since the EDF supports N channels, the power propagation along the EDF is characterized by N&plus;1 differential equations as a function of the direction of propagation, z, of the channels along the length l of the EDF and the time t. By applying an average inversion model to a spatially averaged inversion level of the erbium ions in the fiber, the N&plus;1 partial differential equations are reduced to a single ordinary differential equation. This allows an analytical solution at the boundary and initial conditions of the fiber so that an expression for the power of the signal propagating along the fiber can be obtained. With this expression, the single equation can be solved analytically for the inversion level at any point along the EDF.

Methods of modeling erbium doped fiber amplifiers

A smooth, oblique-angled endface fracture of an optical fiber 39 useful in low reflectance, low insertion loss mechanical splices is achieved by creating tensile stress in the fiber and scoring the fiber at an angle to its longitudinal axis. Tension may be applied by bending the fiber with a flexible platen 16 to which it is affixed, and the scoring may be accomplished by scribing the fiber surface with a sharp point or impressing a notch into the fiber with a blade 28.

Oblique fracturing of optical fibers by angled scoring

A smooth, oblique-angled endface fracture of an optical fiber 20 useful in low reflectance, low insertion loss mechanical splices is achieved by tensioning the fiber while it is in contact with the abrupt edge 23 of an anvil 22 and applying a shearing force to the fiber at a point closely offset from the anvil edge and in a direction substantially perpendicular to the longitudinal axis of the fiber.

Oblique fracturing of optical fibers by offset shearing

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Edison, NJ, United States of America

Virendra S Shah