An optical device includes a non-transparent substrate. The optical device further includes a first optical layer which is at least partially transmissive and at least partially reflective to incident light. The optical device further includes a second optical layer which is at least partially reflective to incident light. The second optical layer is spaced from the first optical layer. At least one of the first optical layer and the second optical layer is movable between a first position at a first distance from the first optical layer and a second position at a second distance from the first optical layer. Movement of the at least one of the first optical layer and the second optical layer between the first and second positions modulates the reflectivity of the device.