Design of an Infrared Shield Device Based on 1D Photonic Crystal

A novel optical low pass filter acting as an infrared shield film is designed. The filter is composed of a 1D photonic crystal structure that blocks infrared light and passes only light of short wavelengths. The low pass filter has a configuration of 1.6(L/2(HL)nHL/2), which was modeled using the transfer matrix method (TMM). Here, H and L denote the high and low refractive indices material. In addition, L/2 matching layers are introduced to reduce the magnitude of ripples in the pass band. The design was done with computational help of optimization using “OpenFilters” software. Transmission greater than 90% in the visible region and reflection greater than 99% in the infrared region has been observed. The properties of the filter by varying the angle of incidence of light at both TE (p-polarization) and TM (s-polarization) modes have been investigated