3D Source Localization and Polarimetry using High Numerical Aperture   Imaging with Rotating PSF
  Rotating-PSF imaging via spiral phase engineering can localize point sources over large focal depths in a snapshot mode. This letter presents a full vector-field analysis of the rotating-PSF imager that quantifies the PSF signature of the polarization state of the imaging light. For sufficiently high image-space numerical apertures, there can be significant wave-polarization dependent contributions to the overall PSF, which would allow one to jointly localize and sense the polarization state of light emitted by point sources in a 3D field. 
Zhixian Yu and Sudhakar Prasad
physics.optics