An in-line polarimeter has been unveiled by General Photonics Corp. The POD-101D is a digital signal processor-powered device designed for high-speed polarization analysis and monitoring. It uses four channels to obtain the four Stokes parameters simultaneously and to measure the instantaneous state and degree of polarization of an input light beam. A USB interface transfers data directly to a computer. The device monitors and analyzes fast polarization changes at a sampling rate of up to 625 kS/s. The supplied PolaView software displays in real time the polarization state, either on a Poincaré sphere window for viewing state-of-polarization traces or on an oscilloscope window for tracking polarization changes over time.