Method for Characterizing Mode Group Properties of Multimodal Light Traveling Through Optical Components

摘要

The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising:
providing a Mode Group Separating optical fiber in an optical path between a light source and said optical component;launching reference pulses of light with a wavelength λt from said light source through said Mode Group Separating optical fiber into said optical component at discrete intervals between a core center and a core radius of said fiber.;The Mode Group Separating optical fiber is a multimode fiber with an α-profile graded index core with an α-value chosen such that said fiber satisfies the following criterion at the wavelength λt:;Δτ·LΔTREF>4;where:
Δτ is a time delay difference between consecutive mode groups;L is a length of said fiber;ΔTREF is a Full Width at Quarter Maximum of said reference pulses.

主权项

1. A method for characterizing mode group properties of multimodal light traveling through an optical component, wherein said method comprises the steps of:
providing a Mode Group Separating optical fiber (5) in an optical path between a light source (1) and said optical component (8); launching reference pulses of light with a wavelength λt from said light source (1) through said Mode Group Separating optical fiber (5) into said optical component (8) at discrete intervals between a core center and a core radius of said Mode Group Separating optical fiber, and wherein said Mode Group Separating optical fiber is a multimode fiber with an α-profile graded index core with an α-value chosen such that said Mode Group Separating optical fiber satisfies the following criterion at the wavelength λt:Δτ·LΔTREF>4 where:
Δτ is a time delay difference between consecutive mode groups expressed in ps/m;L is a length of said Mode Group Separating optical fiber expressed in m;ΔTREF is a Full Width at Quarter Maximum of said reference pulses expressed in ps, where the Full Width at Quarter Maximum of a reference pulse is the difference between the two time values at which the power of the reference pulse is equal to quarter of its maximum value.