US Patent 7508608 Lithographically fabricated holographic optical identification element

A method for fabricating an optical identification element is provided, wherein a removable plate or substrate having photosensitive material fabricated thereon, one or more gratings are written on the photosensitive material, then lines are etched to create one or more separate optical identification elements. The one or more gratings may be written by exposing the photosensitive material to ultraviolet (UV) light. The lines may be etched to create the one or more separate optical identification elements by photolithography to define/create the same.