Modeling of Label-Free Optical Waveguide Biosensors with Surfaces Covered Partially by Vertically Homogeneous and Inhomogeneous Films

Figure 2

The structure of the developed MATLAB algorithm. The input parameters are the parameters of the chip structure and the parameters of the modeled adlayer: the refractive index, the layer thickness, the surface coverage, and the vertical refractive index distribution. The algorithm has two main paths. In the upper one, the real surface mass is calculated with an integral. In the other path, the effective refractive indices were calculated from the input parameters, then these values were applied in the homogeneous and isotropic model resulting in quasihomogeneous surface mass, adlayer thickness, and refractive index. The output parameters of the algorithm are the quasihomogeneous refractive index, the layer thickness, and the ratio of the obtained masses.