Integrated Waveguide Probes as Alternatives to Fiber-Optic Probes for Backscattering and Fluorescence Measurements
Integrated optical probes for detecting backscattered light (i.e. in Raman spectroscopy) show desirable characteristics when compared to conventional fiber probes despite the fact that the latter generally present better collection efficiencies. The major advantages of integrated probes are the reduced size; reduced background noise due to scattering in the probe because of reduced propagation length; potential for monolithic integration with filters, spectrometers and detectors; very small collection volumes, providing high spatial resolution; and polarization maintenance. In our work we demonstrated that in a practically relevant case where scattered light needs to be collected from a thin layer at the samples surface, integrated probes have better collection efficiency than fiber probes do.