Integrated imaging linear polarimeter

The polarimetric vector is a more general descriptor of light than intensity information alone, and it contains physical information about the imaged objects in a scene that traditional intensity based sensors ignore. Polarimeters-devices that measure polarization-are used to extract physical features from an image such as specularities, occluding contours, and material properties. Scientists use polarization information to perform difficult tasks such as image segmentation and surface reconstruction, object orientation, material classification, atmospheric and solar analysis. We will present an integrated CMOS sensor/imager that uses a unique polymer-based polarizing filter to sense two orthogonal directions of linear polarization. The CMOS imager uses analog translinear circuitry to compute, in real-time on the focal-plane, polarization contrast: a measure of the orientation and degree of linear polarization in an imaged scene. We will present the microfabrication technique that enables us to apply CMOS fabrication technology to bulk manufactured poly(vinyl alcohol) linearly polarizing films. This technique allows us to define lithographically micron-scale linearly polarizing regions in polymer-based polarizing filters in order to make a high resolution polarization contrast imager. (C) 1999 Elsevier Science Ltd. All rights reserved.