The Basic Consideration of Sensing Method Using a Metallic Mesh in the Terahertz Range

We report on a novel sensing method in the terahertz region using metallic mesh. Conventionally, the band-pass filter property of a metallic mesh can be adjusted by changing the mesh geometrical parameters. However, the band-pass filter parameters also depend on the refractive index of the medium in the vicinity of the mesh openings. To inspect this effect as a potential measurement principle, we calculated the electric field distribution around the metallic mesh and analyzed the frequency characteristics due to a sample attached to the metallic mesh using the Finite Difference Time Domain method. For bio-molecular sensing, the Electrospray Deposition method was applied in order to spray a uniform layer of protein over a metallic mesh. We observed a correlation between the quantity of protein and the transmission characteristics of the metallic mesh.