Reflection anisotropy spectra of polydimethylsiloxane under a range of mechanically applied stress

Reflection anisotropy spectra of transparent elastomeric polydimethylsiloxane (PDMS) have been determined over the spectral range 1.5 to 5.0 eV for a range of tensile loads. Using a slight wedge shaped sample the spectra from the incident air/PDMS surface are shown to be weak and largely featureless at all loads. By contrast the spectra from the light transmitted through the sample and reflected at the other interface are large in magnitude and …