Patent ID: 8958999
Filing Date: 2015-02-17
Classification: G01N

Abstract:
1. In a surface plasmon resonance sensor having a metal-dielectric interface formed by microfluidic channels integrated with metal-dielectric layer chips, the method comprising: imaging a pair of collimated laser beams at different angles of incidence onto substantially the same spot on a metal nanohole array sample at the metal-dielectric interface to excite surface plasmons on the array sample and forming a pair of transmitted laser beams emerging from the array sample; forming a pair of parallel laser beams corresponding to the pair of transmitted laser beams; obtaining a pair of device transfer function (DTF) signals from the pair of parallel laser beams, where each respective DTF signal has a different angle of incidence and an intensity peak at a different wavelength relative to a reference wavelength; calculating a difference signal from the pair of DTF signals, where the difference signal has positive and negative values about a zero crossing axis which are representative of transmittivity relative to wavelength and where a resulting shift in the location of the difference signal at the zero crossing axis represents a changing refractive index of the dielectric at the metal-dielectric interface.