Polarimetric imaging can provide morphological and structural information of tissue and has demonstrated applications during endoscopy. Polarimetric endoscopy has been shown by conducting polarimetric imaging through customized rigid endoscopes. Here we demonstrate Stokes polarimetric imaging via a commercially available rigid endoscope that can acquire full-Stokes information in a snapshot. This system incorporates two division of focal plane linear polarization cameras, a waveplate and a commercially available rigid endoscope. In addition, the sapphire windows in rigid endoscopes are known for their polarization effects. In this work, the polarization properties of the sapphire windows are carefully measured and calibrated to guarantee the accuracy of the system. Quantified analysis of the system and the imaging results on tissue are provided.
Channeled polarimeters modulate the Stokes parameters onto harmonic carriers of a particular independent domain such as time, space, wavenumber, or angle of incidence. Because the modulation creates many channels within the frequency sampling space of the detector array, channel bandwidth is crucial for this type of device. Much researches has been conducted to exploit more bandwidth in polarimeters that modulate in space, time, or wavenumber along. Our group and others have provided previous theoretical designs for hybrid-domain modulation strategies in order to extend the distance between channels in the Fourier domain through a bandwidth tradeoff approachin order to provide a wider channel bandwidth than systems utilize only one of the corresponding domains. This paper will present results from a a spatio-temporally modulated Stokes polarimeter. The system trades off the bandwidth between space and time to obtain further channel separations. In this work, we demonstrate the system implementation and the experiment results. The experiment compared the spatio-temporal hybrid domain modulated Stokes polarimeter with the spatial and temporal domain only modulated Stokes polarimeter to verify the prediction from the theoretical work. The experimental results indicated that comparing to the spatial and temporal domain only modulated Stokes polarimeters the hybrid-domain modulated polarimeter provides a better image reconstruction and contrast on signals with moderate bandwidth extension. We also consider adaptive reconstruction methods that allow the reconstruction filters to be tailored to the input data. This strategy will allow the bandwidth of the system to be optimally exploited for any particular task.
Multi-domain modulated polarimeters combine carriers on different domains to exploit the bandwidth of the measurement system. However, the inevitable systematic errors in polarimeters will degrade their bandwidth performance, so we developed a new type of multi-domain modulated polarimeter. Compared with conventional polarimeters and our previous separable designs, this new type of system can avoid some of the negative effects (such as the emergence of extraneous channels) caused by the systematic errors. To illustrate the advantages and disadvantages of both systems, both types of Stokes polarimeters are designed based on the same channel structure and their performance is simulated under systematic errors.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.