| 摘要 |
A sheet having a set of axial markings viewable as a contour-dependent, directional image. The image is intact only when the sheet is in substantially a predetermined contour and viewed within a predetermined conical field of view. The figure shows a cross section of an embossed card (60) to the surface of which a microlens sheeting (62) comprising a monolayer of microspheres (64), a binder layer (66), and a layer of adhesive (68) was adhered before embossing. The card and adhered microlens sheeting have been embossed with desired characters (70, 72), such as with the account numbers on a credit card, and the sheeting has assumed a nonplanar contour. The embossing pattern has been altered by removing some characters (70, 72) and adding another (74). Due to the change of the contour of the card, the spatial arrangement between the individual axial markings has been altered, thereby disrupting the image, as represented by the nonparallel arrangement of the lines. Also a method for forming such sheets is presented. |
