OPTICALLY VARIABLE ELEMENT

摘要

The invention relates to an optically variable element having first and second diffraction gratings, which are high-frequency diffraction gratings and thus are reflective into the zeroth order of diffraction. Either a first color is generated by the first diffraction grating and simultaneously a second color different from the first color is generated by the second diffraction grating at a certain angle of rotation and a certain illumination angle, or a visible color is generated substantially only by the first diffraction grating at a first angle of rotation and a visible color is generated substantially only by the second diffraction grating at a second angle of rotation.