Prismatic printing

Abstract

A security document production scheme is presented for the creation of a security document including a prismatic multi-color security image. In accordance with one embodiment of the present invention, a security document is provided comprising a security image defined on a face of the document. The security image is defined along first and second dimensions by the superposition of a primary security image portion and a secondary security image portion. The primary security image portion is defined by security image elements of a first color. The secondary security image portion is defined by security image elements of a second color. The primary security image portion is arranged to include first, second, and third types of security image segments. The secondary security image portion is arranged to include first, second, and third types of security image segments. The first type of security image segment defines an image element tone that decreases in magnitude along the first dimension of the security image and that maintains a substantially constant magnitude along the second dimension of the security image. The second type of security image segment defines an image element tone that decreases in magnitude along the second dimension of the security image and that maintains a substantially constant magnitude along the first dimension of the security image. The third type of security image segment defines an image element tone that maintains a substantially constant magnitude along the first and second dimensions of the security image. The primary security image portion and the secondary security image portion are superposed such that (i) security image segments of the first type in the primary security image portion are superposed with security image segments of the third type in the secondary image portion, (ii) security image segments of the second type in the primary security image portion are superposed with security image segments of the second type in the secondary image portion, and (iii) security image segments of the third type in the primary security image portion are superposed with security image segments of the first type in the secondary image portion.

Dependencies are inferred from the claim text.