Relationship between the size of SiO2 nano spheres and the structure color

According to the emerging requirement in the nano fabrication field of obtaining the quantitative relationship between the nano structure and the color exhibited, a sphere size-color model has been proposed and proved by experiments in this paper. The photonic crystal structures of SiO₂ Nano Spheres with different diameters are fabricated on glass substrate by self-assembly. Simulation is carried out by thin film principle using plane segmentation method, and an equation is fitted to express the relationship between the peak position and the diameter of the nano spheres. The result shows good agreement with that by improved Bragg equation, and matched the experimental results. Thus, the characteristics of its color can be determined by the spectra obtained and the colorimetry principle. Finally, according to the model, the linear relationship between the sphere size and the peak position, namely the color of the sample, has been built.