Realization of Low-Cost Multichannel Surface Plasmon Resonance Based Optical Transducer

Abstract

Abstract This paper demonstrates a low-cost and portable multichannel surface plasmon resonance (SPR) based optical transducer. The system’s portability is achieved through the development of compact web-cam based spectrometer, and edge coupling to the SPR chip. Here, two configurations are presented: single-channel integrated system and two-channel system where the SPR chip and the spectrometer are coupled by a pair of plastic optical fibers. For the two-channel configuration, two different approaches are utilized to extract the optical spectrum: manual region cropping and automatic regions detection. For both approaches, image distortion and the size of the fiber tip affect the measured spectrum. For all configurations, mechanical alignment and mounting are made by 3D printing. The developed systems are tested with water and glycerol solution of different concentrations. The measured sensitivity is in the order of 10‒4 RIU (refractive index unit) for all systems under the ambient condition.

Keywords

• Plasmon
• optical diffraction grating
• optical fibers
• spectrometer
• 3D design
• image processing