An optical structure comprising: a first transparent dielectric layer having a first transparent dielectric layer refractive index greater than or equal to 1.65 at one or more wavelengths in the visible spectral range; a first metal layer disposed over the first transparent dielectric layer , the first metal layer having a first metal layer refractive index, wherein a ratio of the real part (n) of the first metal layer refractive index to the imaginary part (k) of the first metal layer refractive index (k) is greater than or equal to 0.01 and less than or equal to 0.5; a second transparent dielectric layer disposed over the first metal layer , the second transparent dielectric layer having a second transparent dielectric layer refractive index, wherein the imaginary part (k) of the second transparent dielectric layer refractive index is between 0 and 0.5; a second metal layer disposed over the second transparent dielectric layer , the second metal layer having a second metal layer refractive index, wherein a ratio of the real part (n) of the second metal layer refractive index to the imaginary part (k) of the second metal layer refractive index is greater than or equal to 0.01 and less than or equal to 0.5; and a third transparent dielectric layer disposed over the second metal layer , the third transparent dielectric layer having a third transparent dielectric layer refractive index greater than or equal to 1.65 at one or more wavelengths in the visible spectral range, wherein the optical structure is configured to produce a first color in reflection mode and a second color different from the first color in transmission mode. a first transparent dielectric layer having a first transparent dielectric layer refractive index greater than or equal to 1.65 at one or more wavelengths in the visible spectral range; a first metal layer disposed over the first transparent dielectric layer , the first metal layer having a first metal layer refractive index, wherein a ratio of the real part (n) of the first metal layer refractive index to the imaginary part (k) of the first metal layer refractive index (k) is greater than or equal to 0.01 and less than or equal to 0.5; a second transparent dielectric layer disposed over the first metal layer , the second transparent dielectric layer having a second transparent dielectric layer refractive index, wherein the imaginary part (k) of the second transparent dielectric layer refractive index is between 0 and 0.5; a second metal layer disposed over the second transparent dielectric layer , the second metal layer having a second metal layer refractive index, wherein a ratio of the real part (n) of the second metal layer refractive index to the imaginary part (k) of the second metal layer refractive index is greater than or equal to 0.01 and less than or equal to 0.5; and a third transparent dielectric layer disposed over the second metal layer , the third transparent dielectric layer having a third transparent dielectric layer refractive index greater than or equal to 1.65 at one or more wavelengths in the visible spectral range, wherein the optical structure is configured to produce a first color in reflection mode and a second color different from the first color in transmission mode. <EOS>