Abstract

Determination of a single-mode fiber's cutoff wavelength, characteristic of the fiber's index profile, is an important consideration required to avoid modal noise¹ in many applications, including communication systems and sensors. Use of an effective cutoff wavelength, which is characteristic of a particular fiber length or condition of curvature, can be in error by hundreds of nanometers and lead to system design errors. After considerable research and experimentation, two types of experiment have evolved to measure the cutoff wavelength of the LP₁₁ mode in a single-mode fiber: a near-field transmission experiment² and a refracted power experiment.³

© 1982 Optical Society of America