Static subminiature snapshot imaging polarimeter using spatial modulation

Abstract

The spatially modulated snapshot imaging polarimeter can acquire the image and two-dimensional state of polarization using the spatial carrier fringe to encode the full Stokes vectors in a single interference image. It can be used in space exploration, earth observation and detection of biological medicine, land surface and oceans. In an earlier publication, we demonstrated by theoretical analysis that the spatially modulated snapshot imaging polarimeter using modified Savart polariscopes (MSPSIP) is comparable in carrier frequency, signal-to-noise ratio, and spatial resolution to a spatially modulated snapshot imaging polarimeter using conventional Savart polariscopes. In this investigation, the numerical simulation is used to demonstrate theoretical analysis and the feasibility of MSPSIP. Moreover, a geometric ray model is developed to explain the principle and scheme of MSPSIP and derive the expressions of interference intensities. Moreover, a laboratory experiment is conducted to demonstrate the validity of MSPSIP. In addition, we analyze that the interference intensity varies with the direction of polarization analyzer. This investigation enriches the study on MSPSIP and provides a theoretical and practical guidance for study, design, modulation, experiment and engineering of MSPSIP. Furthermore, the MSPSIP operates based on the principle of encodeding polarization information within the spatial modulation of the image. This unique technology allows all Stokes parameters to be simultaneously recorded from each spatial position in an image with a single integration period of the imaging system. The device contains no moving parts and requires no scanning, allowing it to acquire data without the motion artifacts normally associated with scanning polarimeter. In addition to having snapshot imaging and static (no moving parts) capabilities, image processing is simple, and the device is compact, and miniature. Therefore, we believe that MSPSIP will be useful in many applications, such as remote sensing and bioscience.