Abstract:
A method for identifying/authenticating a product. The method includes providing a substrate coupled to the product that includes an identification pattern within a region of interest and imaging the region of interest of the substrate to identify identification particles of the identification pattern. For the identified identification particles in the region of interest, calculating a mathematical value representative of a position of the particle relative to at least one other identification particle and converting the mathematical values of the identified identification particles into an identification value representative of the identified identification particles. The identification value is compared with stored identification values in a database to identify/authenticate the product. Alternately, or in addition, the identification value is compared to an identification value decoded from a bar code imprinted on the product.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a method of identifying and authenticating a product using a bar code reader and, more particularly, to a method of embedding a unique identification pattern in the substrate of a tamper-resistant seal or cap of a product and imaging the identification pattern to authenticate and/or track the product as it travels through it distribution system.  
       BACKGROUND OF THE INVENTION  
       [0002]     There is an increasing concern over counterfeit over-the-counter and prescription drugs entering the U.S. market. This concern is exacerbated because of the ready availability of lower cost prescription drugs from pharmacies and drug stores in foreign countries such as Canada.  
         [0003]     Because of governmental regulations and/or to prevent unauthorized tampering, many prescription and over-the-counter drugs are packaged in containers using tamper-resistant seals. The consumer purchasing a drug product must break or destroy the tamper-resistant seal in order to open the container and access the product. While such tamper-resistant seals effectively thwart tampering, sophisticated counterfeit drug manufacturers may manufacture containers that include a tamper-resistant seal. Thus, tamper-resistant seals do not adequately address the issue of counterfeit drugs.  
         [0004]     There is a need to provide an effective identification and authentication procedure to insure that a purchased drug product is authentic, beyond the use of a tamper-resistant seal on the product container. There is also a need to provide an effective method to track drug products as they move through various stages in the distribution system. Finally, there is a need to accomplish the foregoing objectives using readily available technology and equipment.  
       SUMMARY OF THE INVENTION  
       [0005]     The present invention is directed to a method of identifying or authenticating a product by applying a unique identification pattern to the product, product container or product packaging, such as the product&#39;s tamper-resistant seal and authenticating the product by using a bar code reader to read the identification pattern.  
         [0006]     In one embodiment, the unique identification pattern is a pattern of spaced apart particles embedded in the substrate of a tamper-resistant seal. A region of interest of the seal which includes the identification pattern is imaged by a bar code reader and the identification particles within the region of interest are identified. A perimeter of the identification particles is identified and a geometric center of an area defined by the perimeter is determined. Given the geometric center of the identification pattern perimeter, a polar vector (distance and angle) for each identification particle in the region of interest is determined. The distance magnitudes of the polar vectors are scaled or normalized based on the maximum polar vector distance. Angles between radially adjacent particles are computed. The combination of angular differences and scaled distances comprise a unique electronic signature corresponding to the identification pattern for the product.  
         [0007]     The electronic signature is stored in a database for future authentication of the product as it moves through its distribution system. Additionally, the electronic signature may be affixed to the product by, for example, incorporating the electronic signature into the product&#39;s bar code which would be imprinted on a label of the product or the product packaging. Other methods of affixing the electronic signature to the product would be to incorporate the electronic signature into an RFID (radio frequency identification) tag affixed to the product.  
         [0008]     At any point or node in the distribution system, the product&#39;s authenticity can be verified by imaging the identification pattern and obtaining the electronic signature. This may be done either by: 1) comparing the identification pattern electronic signature with an electronic signature incorporated into the product bar code or RFID tag; or 2) by comparing the identification electronic signature with electronic signatures stored in the central database. If the identification pattern signature matches the bar code electronic signature or RFID electronic signature, the product is authentic. Alternately, if the identification pattern signature matches one of the stored signatures in the database, the product is authentic.  
         [0009]     Tracking of the product through the distribution system is also facilitated since when a product is authenticated at a node, the information regarding the location of the node and the time and date of authentication would be obtained and transmitted to a central database.  
         [0010]     Because the identification pattern signature utilizes differences in angles (between radially adjacent particles) and scaled distances (based on the greatest distance between the center and the furthest particle), the identification pattern electronic signature may be determined regardless of the rotational angle of the bar code reader with respect to the identification pattern, the distance between the reader and the label or a degree of magnification used by the reader to image the identification pattern. When the ultimate consumer opens the product, the tamperproof seal is destroyed preventing its reuse for any counterfeit products.  
         [0011]     These and other objects, advantages, and features of the exemplary embodiment of the invention are described in detail in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  is a schematic representation of an authentication/identification system of the present invention including a container having a wrapped tamper-resistant seal, the wrapped seal including a border and a set of identification particles within the border;  
         [0013]      FIG. 1A  is a schematic elevation view of the wrapped seal of  FIG. 1 ;  
         [0014]      FIG. 2  is a schematic representation of the authentication/identification system of the present invention including front elevation view of a container having a tamper-resistant seal including a cap and integral seal ring, the top surface of the cap including a set of identification particles;  
         [0015]      FIGS. 3A-3D  are schematic diagram depicting selected steps of a process implementing the authentication/identification system of the present invention; and  
         [0016]      FIG. 4  is a flow chart depicting selected steps of the authentication/identification process. 
     
    
     DETAILED DESCRIPTION  
       [0017]     One preferred embodiment of the identification or authentication system of the present invention is shown generally at  10  in  FIGS. 1 and 2 . The system  10  includes a product  13  comprising a container  12  that holds, for example, prescription medication in the form of tablets, capsules or liquid. The product container  12  includes a tamper-resistant seal  14 . As shown in  FIGS. 1 and 1 A, the seal  14  may be a plastic wrap  14   a  that tightly overlies a cap or top  15  of the container  12  and a shoulder portion  12   a  of the container below the cap  15 . Typically, the seal wrap  14   a  includes one or more vertical lines of weakness  14   b  that allow a consumer to more easily remove the wrap from container  12 .  
         [0018]     Alternately, as shown in  FIG. 2 , the seal  14  may be a combination of a threaded plastic cap  16   a  with an integral tamper ring  16   b . In either form, to access the product  13  in the container  12 , the consumer must break the seal  14 , effectively destroying it. In the case of the wrap seal, the consumer must tear or cut the seal before opening the cap or top. In the case of the threaded plastic cap with tamper ring, the consumer must unscrew the cap to access the product. Removing the cap permanently breaks the cap from the integral seal ring. The shape of the container adjacent the seal ring permanently retains the seal ring on the container thereby preventing its removal.  
         [0019]     Embedded in the seal  14  is a unique identification pattern  20  comprising a plurality of spaced apart identification particles  22  within an area or region of interest  25  of the seal  14 . To facilitate reading the identification pattern  20 , the region of interest  25 , that is, the portion of the seal  14  where the pattern  20  is to be imaged may be marked with a border  24  to define the region of interest  25  ( FIG. 1A ). Alternately, the region of interest  25  may be an unmarked, discrete portion of the seal  14  which facilitates imaging. For example, in the case of the cap  16   a  with the integral seal ring  16   b  ( FIG. 2 ), a top surface of the cap  16   c  may define the region of interest  25  without the need for a marked border.  
         [0020]     The particles  22  preferably are embedded in the substrate of the seal  14 , that is, the material that the seal  14  is fabricated from. For example, if the seal  14  is a shrink wrap plastic film  14   a  ( FIG. 1 ) or a cap and seal ring combination  16   a ,  16   b , identification particles may be mixed in with the plastic raw materials during the extrusion process. In this manner, the identification particles are distributed through and embedded in the substrate comprising the seal  14 . Advantageously, by embedding the identification particles in the seal substrate during the fabrication process, each seal  14  will have a unique distribution of identification particles throughout the seal substrate and, more importantly, each seal  14  will have a unique identification pattern  20  of particles  22  within the region of interest  25 .  
         [0021]     The identification particles may be comprised of any of a number of different materials so long as the particles can be easily and clearly identified with respect to the substrate material of the seal  14  within the region of interest  25  when the region  25  is imaged by an imaging device  100 , as explained below. By way of example and without limitation, the identification particles may be discrete pieces of material that fluoresce under UV or other specific wavelengths of illumination. The particles  22  may also be discrete pieces of metal such as small metal chips or shavings. The particles  22  may be small pieces of fabric or other material that changes color under illumination of specific wavelength. Alternately, the particles  22  may be discrete markings that are printed, etched or otherwise impressed on the seal  14  within the region of interest area  25 .  
         [0022]     The identification and authentication system  10  further includes the imaging device  100 , such as an imaging-based bar code reader or scanner. The device  100  is used to image the identification pattern  20  found within the region of interest  25 , that is, within the border  24 . Generally, imaging-based bar code readers or scanners utilize imaging arrays such as CCD arrays or CMOS arrays having a plurality of photosensitive elements or pixels. Light reflected from a target image, e.g., a target bar code imprinted on a product label or product packaging, is focused through a lens of the imaging system onto the pixel array. Output signals from the pixels of the pixel array are digitized by an analog-to-digital converter. Decoding circuitry of the imaging system processes the digitized signals and attempts to decode the imaged target, e.g., the imaged target bar code.  
         [0023]     As noted above, the particles  22  of the pattern  20  may be comprised of visible particles embedded in or imprinted on the seal  14  or, alternately, may be comprised of non-visible particles embedded in or imprinted on the seal  14  that may be imaged only when exposed to illumination having proper wavelengths. If the pattern  20  is comprised of non-visible particles, the reader  100  will necessarily include an illumination source  101  generating a proper wavelength illumination for imaging the particles  22  such that the particles may be discerned by an imaging system  102  of the reader. The reader  100  may also include a second illumination source  103  generating targeting illumination pattern to aid a user of the reader in aiming the reader at the border  24 .  
         [0024]     As will be explained below, advantageously, the system  10  permits any rotational angular orientation between the reader  100  and the region of interest  25 , that is, the reader  100  may be used to read the identification pattern  20  regardless of the rotational angle of the reader  100  with respect to the axis R-R in  FIG. 2 . However, the reader  100  should be aligned with the region of interest  25  such that a front lens  102   a  of the imaging system  102  is aligned with and substantially parallel to the region of interest  25  so as to avoid error associated with a skewed image of the region of interest  25 . That is, a line P 1  along a front lens  102   a  of the imaging assembly  102  should be parallel to a line P 2  along a surface of the region of interest  25  and the imaging assembly should be aligned with the region of interest  25  as shown in  FIG. 2 .  
         [0025]     Utilizing its imaging system  102  and bar code decoding circuitry  104 , the reader  100  may be used both to image and decode a bar code  26  imprinted on a label  28  of the container  12  to obtain certain information and for inventory control purposes and then to identify/authenticate the product  13  as described below. For the decoding of the identification pattern  20 , the reader  100  includes additional identification decoding circuitry  106 , embodied either in software or hardware, such that when the seal  14  is imaged by the reader  100 , the identification decoding circuitry  106  analyzes the captured image, identifies the region of interest  25  and the identification particles  22  within it, ascertains the identification pattern  20  and determines an electronic signature  36  for the product  13 .  
         [0026]     As will be explained below, the product bar code  26  may also advantageously include a coded version  29  of the electronic signature  36  of the product  13 . This facilitates identification/authentication of the product  13  without the need for transmission of the identification pattern electronic signature  36  to a database for authentication because the identification pattern electronic signature  36  may be compared to the decoded bar code electronic signature  29  to authenticate the product  13 .  
         [0027]     A process or method used by the identification decoding circuitry  106  is shown schematically in  FIGS. 3A-3D  and generally at  200  in the flow chart of  FIG. 4 . First, at step  201 , the identification decoding circuitry  106  analyzes the image captured by the imaging system  102  and identifies the region of interest  25 . If there is a marked border  24 , the region of interest  25  will be an area within the border. If there is no marked border, then the region of interest will have to be some discrete area of the seal  14  that the user can readily identify and image, e.g., the upper surface  16   c  of the cap  16   a . The circuitry  106  confines further analysis to the region of interest  25 .  FIG. 3A  shows the border  25 , the region of interest  25  and the identification particles  22  within the region of interest  25 .  
         [0028]     Next, at step  202 , the decoding circuitry  106  identifies the particles  22  within the border  24  and filters out any other non identification particle related marks in the image. For example, particles of dust or other containments that may be disposed within the region of interest  25  are determined by the circuitry  106  not to be identification particles and are subsequently ignored. Similarly, any extraneous markings, such as pen or pencil markings would be filtered out by the circuitry  106 . An identification particle that is partially in and out of the region of interest  25 , for example, particle  22   e , will be considered as an identification particle within the region of interest  25 .  
         [0029]     At step  204 , the identification decoding circuitry  106  determines an outer perimeter  30  defined by the particles  22  within the region of interest  25 . This is shown in  FIG. 3B . At step  206 , the circuitry  106  determines a geometric center C of the area  34  within the perimeter  30 .  
         [0030]     Next, at step  208 , the identification decoding circuitry  106  establishes a Cartesian (x-y) coordinate system with its origin at the center C of the area  34 . This is also shown in  FIG. 3B . At step  210 , the circuitry  106  determines a polar vector V (d, θ) for each particle  22 . For example, particle  22   a  is associated with a polar vector Va having a length or distance d 1  measured from the center C and an angle θ 1 , measured counterclockwise with respect to the positive x axis. Similarly, particle  22   b  is associated with a polar vector Vb having a length d 2  and an angle θ 2 , measured counterclockwise with respect to the positive x axis. This is shown in  FIG. 3C .  
         [0031]     At step  212 , for each of the particles  22 , the identification decoding circuitry  106  scales or normalizes the polar vector length d of the particle by dividing the length d by the largest magnitude value of d of all of the particles  22 , that is, the value of the maximum length d max . In the example, of the particles  11 , polar vector Ve has the maximum length d max , thus, Vc would have a normalized length of Vc=1 while each of the other polar vectors would have a normalized length less than one. For example, the normalized length of particle  22   a  would be d 1norm =d 1 /d max .  
         [0032]     At step  214 , for each particle  22 , the identification decoding circuitry  106  calculates a difference between the polar angle of the particle and the polar angle of the next radially adjacent particle when moving or sweeping in a counterclockwise direction about the center C. For example, for particle  22   a , the angular difference, Δ θ1 , would be the difference between θ 2  and θ 1 : Δ θ1 =θ 2 −θ 1 . This is shown in  FIG. 3D . Thus, for each particle  22  within the region of interest  25 , associated therewith is a normalized length and an angular difference. For example, for particle  22   a , the normalized length is d 1norm  and the angular difference is Δ θ1 .  
         [0033]     At step  216 , the identification decoding circuitry  106 , using a hashing algorithm, converts the series of normalized lengths and the angular differences for each of the plurality of particles  22  into an identification pattern electronic signature  36  (shown in  FIGS. 1 and 2 ) for the container  12 . The electronic signature  36  is a unique string of characters which functions as an identifier for the container  12  and the product  13  in the container.  
         [0034]     There are two ways of using the electronic signature  36  to authenticate the product  13 . If the product  13  includes a coded version  29  of the same electronic signature  29  incorporated into, for example, the product bar code  26  printed on the product label  28 , the identification pattern electronic signature  36  may be compared with the decoded bar code electronic signature  29  to authenticate the product  13  without the need to transmit the electronic signature  36  or to access the central database  110 . If the identification pattern electronic signature  36  matches the product bar code electronic signature  29 , the product  13  is authentic. Advantageously, the bar code  26  is a 2D bard code and the electronic signature  29  encoded in the bar code  26  is encoded with a encryption algorithm (e.g., one way hash) so that only the product&#39;s manufacturer can create the electronic signature  29 .  
         [0035]     Alternately or in addition, the identification pattern electronic signature  36  may be compared with a file of electronic signatures stored in the central database  110  to authenticate the product  13 . If the identification pattern signature  36  matches one of the stored signatures in the database  110 , the product  13  is authentic. It should be recognized that for even a higher level of security both methods may be employed, that is, the bar code electronic signature  29  must match the identification pattern electronic signature  36  and both must match an electronic signature in the database  110  for the product  13  to be deemed authentic.  
         [0036]     At step  218 , the first method is used, namely, the reader  100  decodes the product bar code  16  on the label  28 . In addition to other product-related information, the bar code  26  includes the coded version  29  of the product electronic signature, which is decoded by the reader bar code decoding circuitry  104 . At step  220 , the identification pattern electronic signature  36  is compared to bar code electronic signature  29  by reader comparison circuitry  108  to authenticate the product  13 . At step  221 , if the product  13  is determined to be authentic, the comparison circuitry will notify the user by, for example, actuating a speaker on the reader  100  and/or energizing an LED to indicate authenticity. As would be apparent to those of skill in the art, other methods of incorporating or attaching a second electronic signature onto the product  13 , other than through use of the bar code  26 , are possible. For example, an RFID tag affixed to the product  13  may include an electronic coded version of the product&#39;s electronic signature. If the 2D bar code  26  was read by a bar code reader whose bar code decoding circuitry did not have the capability of reading the bar code electronic signature  29 , the reader could still decode the product-related information in the bar code  26  but would be unable to decode the bar code electronic signature  29 .  
         [0037]     Alternately or in addition to the foregoing, the second method is shown at steps  222  and  224 . At step  222 , the identification pattern electronic signature  36  is transmitted to the central database  110 . At step  224 , the identification pattern electronic signature  36  is compared to a database listing of electronic signatures for authentic products. It is presumed, of course, that the identification pattern electronic signature  36  was determined and stored in the database  110  by the manufacturer when the product  13  was introduced into the container  12  and the seal  14  was applied to the container  12 . If a successful match of the signature  36  is made with a database signature and the tamper-resistant seal  14  is intact, the product  13  is confirmed as authentic and, at step  221 , a transmission is sent back to the reader  100  from the database  110  to confirm authenticity to the user of the reader  100 . For example, a speaker on the reader  100  may emits a distinctive beep or an LED may be actuated to indicate authenticity.  
         [0038]     The two methods of authentication each have advantages. The first method has the advantage of not requiring communications with the central database  110  and, therefore, “stand alone” authentication can be done in the field without the need for a central database.  
         [0039]     The second method of authentication advantageously permits trace and track of the product  13  through its distribution system. The transmission of the electronic signature of the container  12  to the central database  110  may also include additional information such as the time and place that the reading of the identification pattern  20  occurred, an identification number of the reader device  100 , an identification number of the user/company authorized to use the reader device  100 . This information permits tracking of the container  12  and, therefore, the product  13  as it moves through its distribution system from manufacturer to consumer.  
         [0040]     Advantageously, because the container&#39;s identification pattern electronic signature  36  is based on normalized polar vector lengths, the identification/authentication method described above may be successfully utilized regardless of the distance between the reader device  100  and the tamper-resistant seal  14  or the degree of magnification used in the optics of the reader device  100  so long as the border area  25  is successfully imaged and the particles  22  identified.  
         [0041]     Further, since the container&#39;s electronic signature  36  is based on angular differences between the particles  22 , the identification method described above may be successfully executed regardless of the relative angle of rotation between the reader device  100  and the seal  14  with respect to axis R-R ( FIG. 2 ), that is, the rotational orientation of the identification pattern  20  when being imaged by the imaging system  102  is of no consequence since the perimeter  30 , the center point C and the angular differences Δθ between the identification particles  22  within the region of interest  25  will be the same regardless of how the container and seal are rotated with respect to the imaging system  102 . Of course, it is important that the reader  100  is aligned with the region is interest  25  such that the region  25  is substantially parallel to the reader imaging system  102 .  FIG. 2  shows the necessary alignment as the region of interest  25  is the upper surface  16   c  of the cap  16   a , that is, lines P 1  and P 2  are parallel. Yet another advantage of the identification system of the present invention is that the seal  14  is effectively destroyed when a consumer opens the container  12  thereby making it impossible to reuse the seal in conjunction with counterfeit product.  
         [0042]     While the present invention has been described with a degree of particularity, it is the intent that the invention includes all modifications and alterations from the disclosed design falling with the spirit or scope of the appended claims.