Color pigment, which exhibits zero-order diffraction-color effect, useful in pharmaceutical pill, comprises thin dielectric waveguide layer comprising color pigment, where the layer is provided with zero-order diffractive grating structure

摘要

Color pigment, which exhibits zero-order diffraction-color effect, comprises: at least one thin dielectric waveguide layer comprising the color pigment, which exhibits an optical refractive index of at least 0.25, which is greater than the optical refractive index of the material surrounding this layer, where the waveguide layer is provided with a zero-order diffractive grating structure.