A new polarization direction measurement via local Radon transform and error correction

Abstract

Vectorial optical field-based spatially polarization modulation has been widely studied for polarization measurement due to its simple system structure. In this system, the polarization information is encoded in the irradiance image, and polarization measurement can be realized by image processing. The classical image processing methods could not meet the increasing demand of practical applications due to their poor computational efficiency. To address this issue, a new image processing method, combining the rapidity of local radon transform (LRT) and the precision of error correction (EC), was proposed in this paper. Firstly, the polarization direction of the light was coarsely estimated from pixels on several circles. Then, the LRT of the input image was completed while the coarsely estimated direction was the center angle for LRT. Finally, the EC was conducted to get the accurate direction depending on the quantitative link between the error of the coarse estimation and the correlation between the LRTs. Experiments on synthetic and real data demonstrate that, compared to the other state-of-the-art methods, our proposed algorithm is more robust and less time-consuming.