Development of thin-film tunable band-pass filters based hyper-spectral imaging system applied for both surface enhanced Raman scattering and plasmon resonance Rayleigh scattering

Abstract

We describe the development of a hyper-spectral imaging (HSI) system composed of thin-film tunable band-pass filters (TF-TBPFs) and its application to inhomogeneous sample surfaces. Compared with existing HSI systems, the system has a simpler optical arrangement and has an optical transmittance of up to 80% owing to polarization independence. The HSI system exhibits a constant spectral resolution over a spectral window of 80 nm (530 to 610 nm) and tunable spectral resolution from 1.5 to 3.0 nm, and requires only 5.4 s per measurement. Plasmon resonance and surface enhanced Raman scattering (SERS) from inhomogeneous surfaces dispersed with Ag nanoparticles (NP) have been measured with the HSI system. The measurement of multiple Ag NPs is consistent with conventional isolated NP measurements as explained by the electromagnetic mechanism of SERS, demonstrating the validity of the HSI system.