Device and method for polarization-extinction-ratio-measurement

摘要

Disclosed is a power detection device (11) for determining a polarization extinction ratio (PER) for aligning a polarization maintaining optical fiber (PMF) to an optical source providing a linear polarized optical signal. The power detection device (11) comprises a polarization signal splitting device (26), whereby the optical signal transmitted by the fiber (16) is split into a parallel polarized signal component (28) having a signal power value (Pp) and perpendicular polarized signal component (29) having a signal power value (Ps), which are measured by measuring elements (31,32). The polarization extinction ratio is derived from the determined signal power values Ps and Pp. If this ratio is maximized, one of the two principal polarization axes of the PMF (16) is coincident with the linear polarization state of the optical source (36). This allows a maximal maintaining of the polarization state at the end of the fiber.