Polarimeter by rotating polarizer is one of the well-known and classic division of time polarimeter (DoTP). It is generally acknowledged that this kind of polarimeter is time consuming for each measurement although it has simple, accurate and compact performances. In this paper we present a time-integration polarimeter by using a continuous rotating polarizer. The basic principle and the corresponding mathematical expressions are derived. Numeric analysis and experiments are also made in this paper. Experimental results validate the precision and feasibility of the proposed imaging polarization and state of polarization retrieve theory. The frame-frequency of polarization image is 80fps which is limited mainly by the speed of the photodetector in our experiments, and its maximum frame-frequency can achieve over 270fps in theory for some special applications. That may give this kind of classic polarimeter new attractive prospects and life.

A time-integration imaging polarimeter with continuous rotating retarder is presented, and its full-Stokes retrieving and configuration optimization are also demonstrated. The mathematical expression between the full-Stokes vector and the time-integration light intensities is derived. As a result, the state of polarization of incident light can be retrieved by only one matrix calculation. However, the modulation matrix deviates from the initial well-conditioned status due to time integration. Thus, we re-optimize the nominal angles for the special retardance of 132° and 90° with an exposure angle of 30°, which results in a reduction of 31.8% and 16.8% of condition numbers comparing to the original configuration, respectively. We also give global optimization results under different exposure angles and retardance of retarder; as a result, the 137.7° of retardance achieves a minimal condition number of 2.0, which indicates a well-conditioned polarimeter configuration. Besides, the frame-by-frame algorithm ensures the dynamic performance of the presented polarimeter. For a general brushless DC motor with a rotating speed of over 2000 rounds per minute, the speed of polarization imaging will achieve up to 270 frames per second. High precision and excellent dynamic performance, together with features of compactness, simplicity, and low cost, may give this traditional imaging polarimeter new life and attractive prospects.