Patent ID: 7817278
Filing Date: 2010-10-19
Classification: G01N

Abstract:
1. A surface plasmon resonance (SPR) spectrometer sensor apparatus for measuring a property of an analyte substance that can be adsorbed on a surface by directing a beam of incident radiation on the apparatus at an incident angle relative thereto, receiving a beam of reflected radiation off the apparatus, and measuring dips in reflected polarized radiation as a function of at least one of incident angle and wavelength, each of the dips being indicative of a resonance in the apparatus, the SPR spectrometer comprising: a metal layer having a first side which receives incident radiation, and having a second side opposite to the first side; and a dielectric stack, having first and second sides opposite to each other, the first side being in contact with the conductive layer, the second side for receiving an analyte sample to be disposed thereon; the dielectric stack including a plurality of dielectric layers having respective thicknesses and indices of refraction, each successive one of the plurality of dielectric layers having an index of refraction which is alternatingly higher than, and lower than, the indices of refraction of adjacent ones of the plurality of dielectric layers; the plurality of dielectric layers including a first dielectric layer at the first side of the dielectric stack, and a last dielectric layer at the second side of the dielectric stack, the last dielectric layer having a boundary surface for contacting the received analyte sample, and having an index of refraction so as to achieve total internal reflection (TIR) at the boundary surface; wherein the dielectric stack includes: (i) a first dielectric layer, having a first index of refraction, at the first side of the dielectric stack and disposed on the second side of the metal layer; (ii) a second dielectric layer disposed on the first dielectric layer, the second dielectric layer having a second index of refraction less than the first index of refraction; and (iii) a third dielectric layer disposed on the second dielectric layer, the third dielectric layer having a third index of refraction greater than the second index of refraction; and a prism having a surface disposed on the first side of the conductive layer opposite the second side of the metal layer, which second side of the metal layer is in contact with the dielectric stack, wherein the metal layer receives the incident radiation after passing through a portion of the prism including a second surface thereof, wherein the incident radiation is reflected from the metal layer, and wherein the reflected radiation emerges out of the prism from a third side thereof.