This paper shows an implementation of a back focal plane image with and without a grating structure on the surface of a sensor-based surface plasmon resonance. The simulation method is based on a back focal plane of a focal point scanning reflection microscope. Then, a focal point position was taken into account under the proposed calculation. The authors measured qualitative parameters from the surface plasmon-based Kretschmann configuration with and without a dielectric grating in an application. The results showed that the surface plasmon sensor with a modified grating on the surface has higher merit than 20 times. The perspective of this paper has promised the sensor-based surface plasmon resonance and establishes an architecture for enhancing bioanalysis of plasmonic applications.