Angular alignment of a polarization-maintaining optical fiber

Abstract

We describe a simple, fast, and accurate technique for the angular alignment of a polarization-maintaining monomode optical fiber. The method uses simple mechanical supports and is based on the detection of the ellipticity of the light polarization at the fiber output, with the help of a simple rotating polarizer, a photodetector, and an oscilloscope.

Wavelength-dependent orientation of the principal axes of photonic crystal fibers measured by windowed Fourier-transform spectral interferometry

“…The simplest ones are based on the direct observation of the fiber ends using a microscope [1], a CCD camera [2,3] or a polarization alignment instrument that is specially developed for PANDA type PMFs [4]. There are more precise methods, based on monitoring the change in the phase difference between the polarization modes, which rely on the rotation of the polarization plane of the light beam [5] or the rotation of the fiber itself [6]. Other techniques combine the rotation with external perturbations of the fiber, which are often achieved by heating [7][8][9][10][11], applying transversal stress [12], pressure [13] or with a frequency-tunable laser [14,15].…”