Complete Stokes vector analysis with a compact, portable rotating waveplate polarimeter

Accurate calibration of polarization-dependent optical elements is often necessary in optics experiments. A versatile polarimeter device to measure the polarization state of light is a valuable tool in these experiments. Here, we report a rotating waveplate-based polarimeter capable of complete Stokes vector analysis of collimated light. Calibration of the device allows accurate measurements over a range of wavelengths, with a bandwidth of >30 nm in this implementation. A photo-interrupter trigger system supplies the phase information necessary for full determination of the Stokes vector. An Arduino microcontroller performs rapid analysis and displays the results on a liquid crystal display. The Arduino can also be interfaced with a computer to store time series of Stokes vectors. The optical measurement apparatus of the polarimeter is compact and can be placed anywhere on an optical table on a single standard post. The components to construct the device are only a fraction of the cost of commercially available devices, while the accuracy and precision of the measurements are of the same order of magnitude.