TRANSPARENT RETROREFLECTIVE SHEETS CONTAINING DIRECTIONAL IMAGES AND METHOD FOR FORMING THE SAME

摘要

A directional image is created in substantially transparent retroreflective sheeting comprising a monolayer of microlenses and a partially light transmissive mirror disposed at the rear surfaces of at least some of said microlenses. The image is created by irradiation of the sheeting with a laser beam to form axial markings associated with at least some of the micro lenses. The image may be formed in sheeting which has been applied to a document as an overlay.