Different measurement instruments are available to measure the polarization in optical fibers:

• The polarization measurement instrument PSGA is a universal measuring station used to characterize the polarization-dependent properties of optical fibers.
• The in-line polarimeter is used to determine the current polarization state of the light guided in a fiber.
• Further measurement instruments are used to measure polarization-dependent losses, the extinction ratio, and the degree of polarization.

The polarization measurement system PSGA is a multifunctional optical measuring station that is used to produce six polarization states and measure the degree of polarization, polarization state, polarization mode dispersion (PMD), polarization-dependent losses (PDLs), and polarization extinction ratio (PER).

Polarimeters measure the current polarization of light in optical fibers. The polarization is displayed in tabular form as a Stokes parameter or in an oscilloscope form. A graphical representation using a Poincaré sphere is also possible.

The PDL meter PDL-201 determines the polarization-dependent losses and insertion losses of fiber-optic components. Using a very fast, patented algorithm to determine the minimum and maximum optical power level, the polarization-dependent loss (PDL) of the test component can then be calculated.

The PER meter ERM-202 determines the polarization extinction ratio of polarization-maintaining optical components, PM fibers, and PM patch cables. Another use includes measuring the PER during alignment of the polarization-maintaining fibers.

The DOP-201 is used to measure the degree of polarization: it is suited for the high-precision measurement of small and large degrees of polarization. The maximum and minimum search algorithm makes it possible to determine the degree of polarization of light sources or – in connection with an external light source – to characterize the polarization and depolarizers.