To realize high detection precision of surface plasmon resonance（ SPR） biosensor based on phase detection

angle detection and wavelength detection

numerical simulation software for SPR sensor with Kretschmann model was set up using Matlab. Effect of refractive index （ RI） of prism

RI of sample and the thickness of Au thin film on SPR curve of three different detecting method is described. Theoretical analysis results show that the SPR angle increase with the increase of RI of sample when the angle modulation. The phase detection has selectivity to the refractive index of the sensing layer.