Light reflected from the scarab beetles Cetonia aurata (C. aurata) and Chrysina gloriosa (C. gloriosa) has left-handed polarization. In this work the polarizing properties and structural characteristics of the cuticles of these two beetles are investigated with two different techniques: scanning electron microscopy (SEM) and Mueller-matrix spectroscopic ellipsometry (MMSE). SEM is used to get cross section images of the epicutucle and the endocuticle. Thicknesses around 18 μm were measured for both layers for C. aurata and between 12 and 16 μm for C. gloriosa. A layered structure is observed in both beetles. In addition, a cusp-like structure is also observed in C. gloriosa. MMSE showed left-handed near-circular polarization of light reflected on both beetles. For C. aurata this is observed in a narrow wavelength range (500-600 nm) and for C. gloriosa in a wider wavelength range (400-700 nm) when measured on golden areas of the cuticle. C. gloriosa also has green areas where the reflected light was linearly polarized. The results are used in regression modelling. A good model approximation was found for C. aurata for angles up to 60 whereas a good starting point for future work was reached for C. gloriosa.
| Identifer | oai:union.ndltd.org:UPSALLA1/oai:DiVA.org:liu-86339 |
| Date | January 2012 |
| Creators | Fernández del Río, Lía |
| Publisher | Linköpings universitet, Institutionen för fysik, kemi och biologi, Linköpings universitet, Tekniska högskolan |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Student thesis, info:eu-repo/semantics/bachelorThesis, text |
| Format | application/pdf |
| Rights | info:eu-repo/semantics/openAccess |
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