Resonant wavelength shift detection system based on a gradient grating period guided-mode resonance filter

A resonant wavelength detection system based on a gradient grating period guided-mode resonance (GGP-GMR) filter and a linear charge-coupled device is demonstrated. The GGP-GMR used in this work consists of a subwavelength grating structure with a grating period varying from 250–550 nm in increments of 2 nm. We successfully demonstrate that by using this system, we can monitor the shift in a biosensor’s dip wavelength caused by different sucrose concentrations. This technology has the potential to replace a bulky and expensive spectrometer used in most optical biosensor systems. Given its compactness, the system can be integrated with lab-on-a-chip systems for numerous biosensing applications.