Methods for identification and verification

#The invention generally relates to apparatus and methods for identification and verification. More particularly, the invention relates to apparatus and methods for detecting an element or elements intrinsically present—or extrinsically added—in an object by using X-ray fluorescence to identify and verify that object. Even more particularly, the invention related to apparatus and methods for detecting an element or compound intrinsically present—or extrinsically added—in an object by using X-ray fluorescence to identify and verify the elemental taggant(s), thereby tracking and tracing those objects.

#There has been significant interest in apparatus and methods for identifying and verifying various articles or products (or objects) such as explosives, ammunition, paint, petroleum products, and documents. Known methods used to identify and verify such objects generally involve adding and detecting materials like microparticles, bulk chemical substances, and radioactive substances. Similar marking methods include inks that are transparent in visible light are sometimes applied to objects and the presence (or absence) of the ink is revealed by ultraviolet or infrared fluorescence. Other methods include implanting microscopic additives that can be detected optically. Other methods used for identifying and verifying objects include those described in U.S. Pat. Nos. 6,106,021, 6,082,775, 6,030,657, 6,024,200, 6,007,744, 6,005,915, 5,849,590, 5,760,394, 5,677,187, 5,474,937, 5,301,044, 5,208,630, 5,057,268, 4,862,143, 4,485,308, 4,445,225, 4,390,452, 4,363,965, 4,136,778, and 4,045,676, as well as European Patent Application Nos. 0911626 and 0911627, the disclosures of which are incorporated herein by reference.

#As well, there has been significant interest in using similar methods to collect and record data about an object. In particular there has been significant interest to track and trace objects using these methods, e.g. to prevent loss or counterfeiting. Recognizing that manual data collection and keyed data entry were inefficient and error-prone, many industries adopted bar code technology in the mid 1980s. Bar codes were determined, however, to not be suitable for direct part (or object) marking (DPM). Instead, bar codes were used on labels or other packaging for the object or part.

#FIGS. 1, 2a, 2b, 3, 4a, 4b, and 5-8 are views of one aspect of apparatus and methods according to the invention, in which:

#FIG. 1 generally depicts the operation of XRF;

#FIG. 2a and 2b illustrate the operation of XRF at the molecular level;

#The following description provides specific details in order to provide a thorough understanding of the invention. The skilled artisan will understand, however, that the invention can be practiced without employing these specific details. Indeed, the invention can be practiced by modifying the illustrated apparatus and method and can be used in conjunction with apparatus and techniques conventionally used in the industry. For example, the invention is described with respect to apparatus and methods for identifying and tracking/tracing objects using taggants in combination with two-dimensional data labels. The invention described below, however, could be easily modified to be used in combination with other anti-counterfeiting technologies. Indeed, the invention could be modified to be used in place of (or in addition to) other anti-counterfeiting technologies.

#The invention uses x-ray fluorescence analysis to detect at least one elemental taggant intrinsically or extrinsically present in the material of an object. With x-ray fluorescence (XRF) analysis, x-rays produced from electron shifts in the inner shell(s) of atoms of the taggants and, therefore, are not affected by the form (chemical bonding) of the article being analyzed. The x-rays emitted from each element bear a specific and unique spectral signature, allowing one to determine whether that specific taggant is present in the product or article.

#FIGS. 1, 2a, and 2b represent how it is believed XRF generally operates. In FIG. 1, primary gamma rays or x-rays 40 are irradiated on a sample of a target material 46 of article 42. Secondary x-rays 44 are emitted from that sample of target material 46.