An ellipsometric surface plasmon resonance system for quantitatively determining the normal of a sensor surface and multi-channel measurement

We present a three-intensity ellipsometric technique to obtain analytical solutions for the surface inclination and ellipsometric parameters under surface plasmon resonance (SPR) condition. The relation between the phase change of ellipsometric parameter and tilt angle of the test surface was obtained after a careful calibration procedure. Four-channel SPR images with different refractive indexes liquids and immobilized biomolecules were demonstrated. Also, the alignment of surface normal and the collimation of the incident light beam were examined in the measurement.