Santec Europe Ltd. offers a device for measuring polarization extinction ratio, optical power and polarization angle in real time. The PEM-310 simultaneously displays the measurements on the front panel and can output the results via a general-purpose interface bus, RS-232 or an analog interface. The device can cover all the wavelengths used in telecommunications systems, including 980, 1310, 1480 and 1550 nm. It is suitable for aligning the polarization axes of fibers and components, and for polarization-state monitoring in optical fiber systems. It has an optical power operation range of -40 to +10 dBm, and has resolution of 0.1 dB over a wide dynamic range and 40 dB for polarization extinction ratio. A high-power version for use up to +23 dB also is available.