Theoretical and practical aspects of optical scattering measurements

Sammanfattning

Characterizing the optical scattering properties of materials is usefulfor many purposes. There are also multiple ways to describe scatteringfrom matter. One way, from a macroscopic point of view, is to measurethe bidirectional scatter distribution function (BSDF) with an opticalscattering measurement device, such as a scatterometer. On the otherend, mathematical descriptions such as Mie theory provide an exact de-scription of scattering from well-defined objects. In this work we considerboth theoretical and practical aspects of optical scattering measurementsin the development of an optical scattering measurement device. Firstwe study electromagnetic scattering theory, especially Mie theory. Thenwe study optical models, from a geometrical-optics point of view, of thedetector system of an optical scattering measurement device. We developand configure a detector system and also a BSDF mockup device withwhich we perform some BSDF measurements on a sample of milk. Wecompare the experimental result with the result from a simulation of anoptical scattering model for milk based on Mie theory. The results seemto stay within the same order of magnitude but the uncertainties of themeasurements and the experimental setup are too high to find any clearcorrespondence between the results.