Elastic backscattering spectroscopic microscopy.

The spectral properties of elastic light-scattering signals have been shown to provide a wealth of information on nanostructures and microstructures. We present elastic backscattering spectroscopic microscopy that allows simultaneous acquisition of microscopic images and backscattering spectra at each pixel. Within a single homogeneous micrometer-scale particle we observe two distinct and highly localized spectral oscillation features that arise from different optical paths: (1) surface waves (e.g., the ripple structure) and (2) a not previously reported anomalous ripple structure that is due to the interference of waves scattered from front and back surfaces at the particle's center. We also demonstrate that the spectroscopic data can provide nanoscale structural information beyond what conventional microscopy reveals.