To improve the performance of existing guided-mode resonance(GMR) anti-counterfeiting grating, a tri-color shift device based on a one-dimensional(1D) singly periodic rectangular structure and Zn S film is reported. By turning the azimuths, the proposed device exhibits tri-color shifts of blue, green, and red for both TE and TM polarizations simultaneously. As the natural light can be considered as a superposition of TE and TM polarizations, in order to achieve the azimuth-tuned tri-color shifts of blue, gr...