Polarization Imaging Camera Fundamentals

Operating Principle

A polarizer array with elements the same size as the pixels of the CCD is deployed in front of the CCD (upper right diagram). Thus each pixel detects a particular polarization.

By calculating the intensity of each of the four neighbouring pixels that constitute a unit cell, the
  1.  Polarization Axis Azimuth, Theta
  2.  Average Luminance, A
  3.  Polarization Component Strength, B
are determined.

Conventionally, because integration of the polarizer was extremely difficult, it was necessary to rotate a polarizer in front of the camera to obtain the above described polarization state information. Thus the subject had to remain stationary, and animation was not feasible.

Using the autocloning method, a high quality polarizer array can easily be fabricated in one process (see SEM to right). As a result, it has been possible to shift the paradigm of acquiring polarized light information from temporal partitioning to spatial partitioning. The PI-100 is capable of heretofore unprecedented animation and high speed analysis of polarization distributions.