Hybrid optical-digital design for cost-effective standoff Raman detection system utilizing a night-vision intensified spectrometer

This study presents the development and prototyping of a cost-effective standoff Raman detection system employing a custom night-vision (NV) intensified spectrometer, enabled by an integrated optical-digital design strategy. The optical design and simulation were focused on maximizing light throughput and achieving low-noise signal collection, while digital post-processing employed a non-blind deconvolution algorithm to restore spectral resolution degraded by the NV intensifier. The system was constructed using commercial off-the-shelf components and 3D-printed parts, ensuring flexibility and modular assembly. Standoff Raman detection was successfully demonstrated for explosive-like compounds containing urea (CO(NH₂)₂), nitrate (NO₃^-), and sulfate (SO₄^2-) functional groups, achieving a high signal-to-noise ratio of ∼10² at distances at least 60 m. Furthermore, the system demonstrated a uniform spectral resolution of approximately 1 nm, sufficient to differentiate the nitrate group in similar compounds. This hybrid approach enables efficient utilization of the NV-intensified spectrometer, significantly reducing both the cost and complexity of a standoff Raman detection system while providing reliable long-range detection capabilities.