This book was motivated by a short course on polarimetric remote sensing that I taught for industry about a year ago. I had supervised three doctoral students on thesis topics involving this subject and when I was asked to teach the course I thought it would be relatively easy to pull the course material together. In the months leading up to the course I discovered two things. First, as is so often the case, in preparing to teach the topic I found I knew far less than I thought I knew and dramatically less than I needed to know to teach a course. Second, I found that while there is a good treatment of polarization principles in the electro-optics literature, the treatment from the remote sensing perspective was quite scarce. In particular, while there were many journal and conference papers on specific topics, there was nowhere to send a student to get a good start on the fundamentals that they would need to prepare to delve into the more specific topics in the journals. So, to make a long story short, with considerable effort, I pulled together a variety of material and taught the course.
Afterwards, I realized I had the foundation for an introductory book that might save others getting started in this field from a similar effort. As a result, I spent the last year fleshing out the initial material, with a good deal of help from dedicated colleagues. The final book focuses on passive electro-optical polarimetric remote sensing in the visible through the thermal infrared (0.4â14 Î¼m).
Polarimetric remote sensing is a relatively new field. It has champions who tout that polarimetric measurements are uncorrelated with traditional measurements of the magnitude and spectral content of the electromagnetic signal and should therefore add significant information. Likewise, it has detractors who point out that often the sought for contrasts between targets and backgrounds or between phenomena are not observed or are not as dramatic as they might be using some other sensing approach. I believe the jury is still out regarding how much utility we will eventually find in passive polarimetric remote sensing and what its role should be relative to other sensing approaches (e.g., multispectral). One of the main reasons for this is that polarimetric signatures are a rather involved function of source, target, and sensor geometry. Potential users must develop a more thorough knowledge of the relevant source-target-propagation-sensor physics to determine the true utility of this modality for their application. Once we understand and apply the relevant physics, we can develop tools to make it easier for other users to guide collection, processing, and analysis to improve signature contrast and determine the true utility of polarimetric remote sensing. It is for these students of the relevant physics (myself included) that I have written this book. I hope you find it a useful starting point for exploring this largely unexplored field.
As I listen today to the waves crashing on the beach, drowned out periodically by the thunder rumbling across the sky and watch the bay lit up by lightning, I can't help but be reminded how rich and complex nature is and how rewarding its study can be.
John R. Schott, Ph.D.
Port Colborne, Ontario
© 2009 Society of Photo-Optical Instrumentation Engineers