Book

book

Optical Scattering: Measurement and Analysis, published by SPIE Press is now available in it’s third edition and may be purchased from SPIE here.

The Preface to the third edition is copied below.

Preface

When the last edition was published I really didn’t expect another one would be written. Instrumentation was being sold that could measure down to the practical noise floor associated with Rayleigh scatter from air molecules. The math for scatter from optically smooth surfaces was understood and experimentally confirmed. Round robin tests had been performed finally confirming that we all spelled BRDF the same way. What else could possibly be needed? Then I entered the semiconductor industry for several years, where signals are scatter from small isolated defects and roughness scatter is a noise source, and realized that the book really only covered half the scatter issues for that industry. Other industries became concerned about scatter from much rougher surfaces (solar energy and appearance to name two) and this opened another set of scatter related problems. My SPIE Course, which was the inspiration for the book, kept changing to keep up with industry concerns and eventually I realized there was material for another edition. Then a friend told me that the book was old enough that some of his colleagues assumed I was dead and that pushed me into action. As a result the book you are holding has three new chapters, several new sections and a rewrite of the older material. I expect in another decade or two there will be enough material for yet another edition, but without serious advances in medical science as well, I doubt if I will be writing it.

Several hundred million dollars worth of scatterometers have been sold in the semiconductor industry since publication of the last edition. They call them “particle scanners,” but they are just scatterometers automated for beam scanning and wafer handling. As you read this several thousand of these instruments are hard at work and they do so 24/7. International standards are used to support the specification of these instruments and I was lucky enough to become involved in writing them in both ASTM and SEMI. One of the new chapters reviews scatter related standards.

Just as we learned to model scatter from residual roughness on optics some really smart people leaned how to model scatter from discrete surface defects. Scatter signals can now be used to determine whether that flash of light in a scanner is from a pit or a particle. Unfortunately a lot of these models are proprietary (but not all) and there is a chapter on capabilities and availability of discrete scatter models.

Beauty is in the eye of the beholder and, as you are well aware, what we see is scattered light. As a result industries concerned with appearance have also learned about BRDF and its measurement. Examples are new car interiors, beer cans and movie scenes of everything from dinosaurs to spacecraft. These kinds of problems often require full hemispherical measurement (not just incident plane scans) and array camera instrumentation has been developed. There is a new chapter on Appearance and new sections involving instrumentation and scatter from optically rough surfaces.

So once again dear scatterbrain, I am hoping you find the new edition worth my time and your (company’s?) money.

John C. Stover