Guided Mode Resonance Transmission Filters Working at the Intersection Region of the First and Second Leaky Modes

Based on the guided mode resonance effect, single-layer transmission filters are presented. It is found that there is an intersection region in which the strong modulation waveguide modes TE₀ and TE₂ can be simultaneously excited by the second and first diffraction orders, respectively. A very high transmission peak emerges when the leaky modes interact with each other. Based on the normalized eigen−function of a single-layer waveguide grating, the high resonance transmission filters can be designed at any central wavelength. In order to demonstrate this concept, we design narrow line-shaped band pass filters with a central wavelength at 0.8, 1.06 and 10.6 µm .