In part, the invention relates to a single clad fiber to multi-clad optical fiber connector for use in applying excitation light to a sample and obtaining reflected light from the sample. The connector can include a dual clad optical fiber portion and a single clad optical fiber portion in optical communication with the dual clad optical fiber portion. In one embodiment, a core of the dual clad optical fiber portion and a core of the single clad optical fiber portion have substantially similar indices of refraction. In one embodiment, excitation light is propagated by the core of the dual clad optical fiber. Further, in one embodiment, light reflected by the sample is propagated by the first cladding layer of the dual clad optical fiber portion.