Diffractive pigment flakes are selectively aligned to form an image. In
one embodiment, flakes having a magnetic layer are shaped to facilitate
alignment in a magnetic field. In another embodiment, the flakes include
a magnetically discontinuous layer. In a particular embodiment,
deposition of nickel on a diffraction grating pattern produces magnetic
needles along the grating pattern that allow magnetic alignment of the
resulting diffractive pigment flakes. Color scans of test samples of
magnetically aligned flakes show high differentiation between
illumination parallel and perpendicular to the direction of alignment of
the magnetic diffractive pigment flakes.