The DOP-201 measures and displays the Degree of Polarization (DOP) of a light source in real time on the front panel display. The instrument incorporates a patented maximum & minimum search technique that accurately measures both low and high DOP. This technique is superior to polarimeter-based methods that are inaccurate at low values of DOP as well as scrambler-based methods which are less accurate at high values of DOP. The instrument’s wide range includes the S, C and L bands, without calibration. Simultaneous measurement of DOP and optical power level of the light source under test can be used to obtain DOP power dependence and to ensure low insertion loss during depolarizer manufacturing. The DOP-201 replaces the DOP-101 and offers higher measurement speed, higher measurement accuracy and resolution, wider operating power range, a better and brighter display (see example of OLED display below), and the addition of an analog output port for integration in automated test stations. General Photonics DOP 201 Degree Polarization Meter