A novel millimeter wave band-pass frequency selective surface transparent to infrared wave

A novel millimeter wave (MMW) frequency selective surface (FSS) is proposed. The periodic elements of FSS are etched on a layer of semiconductor film. The film is transparent at infrared (IR) wavelength and periodic elements are designed to decrease the transmission loss due to the finite conductivity of the film at millimeter wavelength. An FSS with the resonant frequency at 35 GHz is designed. Simulated results show that the transmission properties of the FSS for MMW illuminated by both TE and TM incidences are satisfactory. In the meantime, the area of the elements is no more than 18% of the total FSS area that ensure the good transparency of the IR wave.