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Polarization Analyzer series SK010PA

Exhibition Setup

Universal measurement and test systems for coupling laser beam sources into polarization-maintaining fiber cables.
  • First setup: Optimization of the polarization axis alignment during fiber-coupling.
  • Second setup: Adjustment of quarter-wave plates
More information on the Polarization Analyzer SK0101PA can be found here.

Description

The Polarization Analyzer series SK010PA is a universal measurement and test system for coupling laser beam sources into polarization-maintaining fiber cables. It was developed from practical experience with a focus on high usability and procedures for the optimization of the alignment

Exhibition setup

The SK010PA exhibition shows how to correctly align the polarization axis of the fiber to that of the laser source when fiber-coupling. It also demonstrates how to visualize the different polarization states exiting a fiber collimator with integrated quarter-wave plate.

First setup: Optimization of the alignment of the polarization axis during fiber-coupling.

The procedure starts with the recording of polarization states ex fiber while the fiber is carefully bended, to cause the exit polarization to fluctuate. A circle is then automatically fitted to the data points on the Poincaré sphere, and the mean and minimal PER are displayed.

The radius of this circle indicates the quality of the ­alignment, since it shows the angle deviation between the fiber polarization axis and the linear SOP of the incoming radiation. For an optimally aligned ideal fiber, the data circle converges to a single point, the center of the circle.

For a non-optimum alignment the circle on the Poincaré sphere has a large radius at first.  

SK010PA PER adjustment routine - bad alignment
During continuous measurement of the SOP ex fiber, the polarization axis of the source is rotated with respect to the fiber axis, here using a half-wave plate. 

The optimum alignment is reached when the SOP ex fiber approaches the circle center on the Poincaré sphere as far as possible.

A second measurement then determines the PER of the optimized polarization alignment of the fiber.
SK010PA PER adjustment routine - good alignment

Second Setup: Alignment and Quantification of retardation optics  

The SK010 Polarization Analyzer can be used to align and quantify retardation optics, e.g. fiber collimators with integrated quarter-wave plates series 60FC-Q.

The outcome polarization is adjusted by rotating the quarter-wave plate with respect to the input polarization. A full rotation corresponds to a figure-of-eight on the Poincaré sphere. Circularly polarized light is set when the poles are reached: right-handed circular polarization at the north pole, and left-handed polarization at the south pole.