Compact Raman Fiber Optic Probe with Inline Spectral Filtering

In this SBIR effort, Nikira Labs Inc. proposes to develop a compact Raman fiber optic probe with inline spectral filtering that improves fiber-coupled Raman measurements by filtering out Raman scattering from the excitation fiber and elastically scattered laser light from the collection fibers. The technology will enable compact fiber probes for Raman studies and complement existing NIST Raman spectroscopy efforts including tissue studies and broadband coherent anti-stokes Raman scattering. In Phase I, we will demonstrate technical feasibility by fabricating a set of Raman probes that include a central excitation fiber surrounded by collection fibers. A custom, dielectric coating will be deposited on the face of the excitation fiber to serve as a bandpass filter and remove wavelengths generated by inelastic Raman scattering within the fiber. Likewise, dielectric coatings will be deposited on the collection fiber faces to reject elastically scattered laser light and only pass Raman signal. The fibers will be integrated into a probe assembly and extensively tested on Raman standards, highly scattering compounds, and a phantom tissue sample. Contingent on availability, one probe may be delivered to NIST for testing in their Raman systems. Finally, the Phase I results will be used to design a Phase II system.