Patent Publication Number: US-9852596-B2

Title: Security tag and method of using same to facilitate authorized removal of inventory items from controlled areas

Description:
BACKGROUND OF THE INVENTION 
     Electronic Article Surveillance (“EAS”) systems are often used by retail stores in order to minimize loss due to theft. One common way to minimize retail theft is to attach a security tag to an article such that an unauthorized removal of the article can be detected. In some scenarios, a visual or audible alarm is generated based on such detection. For example, a security tag with an EAS element (e.g., an acousto-magnetic element) can be attached to an article offered for sale by a retail store. An EAS interrogation signal is transmitted at the entrance and/or exit of the retail store. The EAS interrogation signal causes the EAS element of the security tag to produce a detectable response if an attempt is made to remove the article without first detaching the security tag therefrom. The security tag must be detached from the article upon purchase thereof in order to prevent the visual or audible alarm from being generated. 
     One type of EAS security tag can include a tag body which engages a tack. The tack usually includes a tack head and a sharpened pin extending from the tack head. In use, the pin is inserted through the article to be protected. The shank or lower part of the pin is then locked within a cooperating aperture formed through the housing of the tag body. In some scenarios, the tag body may contain a Radio Frequency Identification (“RFID”) element. The RFID element can be interrogated by an RFID reader to obtain RFID data therefrom. 
     The EAS security tag may be removed or detached from the article using a detaching unit. Examples of such detaching units are disclosed in U.S. Pat. No. 5,426,419 (“the &#39;419 patent), U.S. Pat. No. 5,528,914 (“the &#39;914 patent”), U.S. Pat. No. 5,535,606 (“the &#39;606 patent”), U.S. Pat. No. 5,942,978 (“the &#39;978 patent”) and U.S. Pat. No. 5,955,951 (“the &#39;951 patent”). The detaching units disclosed in the listed patents are designed to operate upon a two-part hard EAS security tag. Such an EAS security tag comprises a pin and a molded plastic enclosure housing EAS marker elements. During operation, the pin is inserted through an article to be protected (e.g., a piece of clothing) and into an aperture formed through at least one sidewall of the molded plastic enclosure. The pin is securely coupled to the molded plastic enclosure via a clamp disposed therein. The pin is released by a detaching unit via a probe. The probe is normally retracted within the detaching unit. Upon actuation, the probe is caused to travel out of the detaching unit and into the enclosure of the EAS security tag so as to release the pin from the clamp or disengage the clamp from the pin. Once the pin is released from the clamp, the EAS security tag can be removed from the article. 
     While EAS security tags do help reduce retail theft, their use requires customers to wait in lines to complete purchases, because the tag must be removed so as not to trigger an EAS security alarm when leaving the store. 
     SUMMARY OF THE INVENTION 
     This disclosure concerns implementing systems and methods for security tag detachment or deactivation authorization. According to one aspect, the invention concerns a method to selectively facilitate the authorized removal from a controlled area of items which have been marked with an item identification code. In an exemplary arrangement, the item identification code can be a Universal Product Code (UPC) or Electronic Product Code (EPC) associated with the item. 
     The method involves attaching to each item which is disposed in the controlled area a security tag detectable by an Electronic Article Surveillance (EAS) system. A transaction software application is provided for one or more portable mobile communication devices (PMCDs). The transaction software application is operable to facilitate use of the PMCD to obtain the item identification code and participate in a wireless communication session with a transaction server to receive an authorization for release of the item from the controlled area. For example, the wireless communication session may comprise a purchase transaction in which the PMCD is used to facilitate purchase of the item. 
     The transaction software application is further operable to facilitate use of the PMCD to access from the security tag certain security tag information which is available on or in the security tag. The transaction software causes the PMCD to use the security tag information to compute an unlock code for the security tag. In some embodiments, the unlock code is encrypted as a security measure. The transaction software application is further arranged to facilitate use of the PMCD to wirelessly communicate the unlock code to the security tag after the authorization for release has been received. The security tag is responsive to receipt of the unlock code to unlock a locking mechanism in the security tag or deactivate the security tag. 
     According to one aspect, the security tag information is accessed by the PMCD from the security tag by using an imaging device of the PMCD to scan a barcode disposed on an exterior housing of the security tag. Thereafter, the unlock code is wirelessly communicated to the security tag using an optical communication link. The optical communication link advantageously makes use of hardware elements which are commonly found on conventional PMCDs. For example, the PMCD can make use of a user interface display device or an optical emitter (a camera flash element) disposed on the PMCD to communicate the encrypted unlock code to the security tag. In certain scenarios, the security tag information is accessed by the PMCD from the security tag using a short range wireless communication protocol instead of the optical scanning method. 
     According to a further aspect, the security tag information is chosen to be a public key. In such a scenario, the PMCD uses the public key to compute the encrypted unlock code. The encrypted unlock code thereafter is decodable by the security tag from which security tag information was obtained by using a private key which is stored in the security tag. 
     The invention also concerns a security tag for an Electronic Article Surveillance (EAS) system. A security tag includes a security tag housing and a barcode visibly disposed on exterior of the security tag housing specifying security tag information. At least one EAS detection element is disposed within the security tag housing. The EAS detection element is responsive to an EAS system interrogation signal for producing a detectable electromagnetic signature when the security tag is present within an EAS detection zone. Also disposed within the security tag housing is a computer processing device and a wireless communication receiver operatively coupled to the computer processing device. The computer processing device is responsive to a coded signal determined in accordance with the security tag information and received using the wireless communication receiver to perform at least one security tag action. In some embodiments, the coded signal can be encrypted using a public key specified by the security tag information. In that case, the security tag advantageously includes a private key stored in a data memory of the security tag to decrypt the coded signal. 
     According to one aspect, the security tag includes a latch release mechanism that is responsive to the computer processing device. In such a scenario, the security tag action may comprise transitioning the latch release mechanism to an unlatched state to facilitate release of the security tag from an article. The computer processing device can be further arranged to cause the latch release mechanism to remain in the unlatched state for a predetermined period of time before automatically causing the latch release mechanism to revert to a latched state. According to a further aspect, the EAS detection element is configured to be selectively disabled responsive to the computer processing device. In such a scenario, the security tag action can comprise disabling the EAS detection element to facilitate the removal of the security tag from an EAS controlled area without setting off an EAS alarm. 
     The wireless communication receiver incorporated into the security tag is advantageously selected to be an optical receiver that is operable for receiving the coded signal in an optical format. Also, the security tag can include at least one of an optical emitter and an audio annunciator which are responsive to the computer processing device. The computer processing device is advantageously configured to use at least one of the optical emitter and the audio annunciator to signal that the at least one security tag action has been performed. 
     According to a further aspect, the security tag for an Electronic Article Surveillance (EAS) system as described herein can comprise a security tag information dissemination device which is configured to facilitate short range wireless communication of the security tag information to a PMCD. The security tag can be similar to the security tag described above. But information dissemination device can be a barcode affixed to an exterior of a housing of the security tag as described above, or can be a near field communication wireless radio frequency communication device. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Embodiments will be described with reference to the following drawing figures, in which like numerals represent like items throughout the figures, and in which: 
         FIG. 1  is an illustration of an exemplary architecture for a security tag detachment method and system which permits customers to use their portable mobile communication devices to perform security tag unlocking operations. 
         FIG. 2  is an illustration which is useful for understanding how a PMCD can obtain certain security tag information from a barcode disposed on an exterior housing of the security tag. 
         FIG. 3  is a block diagram that is useful for understanding certain aspects of a security tag as described herein. 
         FIG. 4  is an illustration which is useful for understanding how a PMCD can optically communicate an unlock code to a security tag. 
         FIGS. 5A through 5C  collectively provide a flow diagram of an exemplary method for security tag detachment or deactivation authorization. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     It will be readily understood that the components of the embodiments as generally described herein and illustrated in the appended figures could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by this detailed description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. 
     Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussions of the features and advantages, and similar language, throughout the specification may, but do not necessarily, refer to the same embodiment. 
     Furthermore, the described features, advantages and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. 
     Reference throughout this specification to “one embodiment”, “an embodiment”, or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the present invention. Thus, the phrases “in one embodiment”, “in an embodiment”, and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. 
     As used in this document, the singular form “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. As used in this document, the term “comprising” means “including, but not limited to”. 
     Mobile shopping apps, shopping websites and self-checkout solutions are becoming more prevalent in retail stores. A mobile shopping app allows a customer to complete a purchase transaction using their personal mobile communication device (PMCD) such as a smart phone. Presently, there is no way for a retail store to provide a customer with authorization to detach and/or deactivate security tags attached to protected retail items after they customer completes a purchase using their PMCD. Accordingly when a customer uses their PMCD for to complete a mobile shopping app purchase, the security tags attached to the purchased products will trigger an alarm at a retail store&#39;s exit. For tag deactivation, some retailers have a deactivation device tied to a fixed POS. Deactivation of a security tag is only enabled when there is a scanned UPC. However, there is no verification that the correct security tag is deactivated. 
     The systems and methods discussed herein facilitate security tag detachment/deactivation by a customer using their PMCD after using the PMCD to complete a successful purchase transaction. Accordingly, the present solution facilitates the use of mobile shopping applications and self-checkout solutions in retail establishments that would not otherwise be possible due to the use of security tags. The present solution provides advantages to retailers by (1) reducing labor costs for checkout and security tag detachment/deactivation and (2) allowing better management of customers due to mobile checkout options available. The present solution also provides advantages to customers by (1) allowing customers to self-pay using a mobile shopping applications and self-checkout solutions in store with products protected by security tags. As such, there is no need for the customers to stand and wait in checkout lines. 
     A mobile shopping app which has been downloaded to a PMCD enables the scanning of Universal Product Code (UPC) or Electronic Product Code (EPC) associated with the product. As is known, a UPC is a barcode symbology (i.e., a specific type of barcode) that is widely used for tracking trade items in stores. If a conventional UPC is utilized, the UPC bar code can be printed on a label or tag attached to the physical object or trade item being identified. If an EPC solution is used, the EPC information can be encoded in an RFID tag that uniquely identifies the product by including the EPC. In some scenarios, the RFID tag may be incorporated into the security tag as a dual technology tag for a single security tag option or as a separate tag on the product. The dual technology security tag may have a barcode identifying the encoded EPC. Alternatively or additionally, the EPC may be encoded in a way where the UPC is included in the EPC. 
     Exemplary Systems 
     Referring now to  FIG. 1 , there is provided a schematic illustration that is useful for understanding the inventive arrangements. An exemplary anti-theft system  100  comprises a retail store facility  102  including an EAS system  104 . The EAS system  104  comprises a monitoring system  110  and at least one security tag  106 . Although not shown in  FIG. 1 , the security tag  106  is attached to an article  112 , thereby protecting the article  112  from an unauthorized removal from the retail store facility  102 . The monitoring system  110  establishes a surveillance zone (not shown) within which the presence of the security tag  106  can be detected. The surveillance zone is established at an access point (not shown) for the retail store facility  102 . If the security tag  106  is carried into the surveillance zone, then an alarm is triggered to indicate a possible unauthorized removal of the article  112  from the retail store facility  102 . 
     During store hours, a customer (not shown) may desire to purchase the article  112  using their PMCD  118 . The PMCD  118  is a handheld communication device running the retail transaction application. The handheld communication device can be, but is not limited to, a cellular phone, a smart phone, a portable computer, a tablet, or a personal digital assistant. PMCDs are well known in the art and therefore will not be described here in detail. However, it will be appreciated that a PMCD  118  can include a processing element  140  such as a microprocessor, a data store  142  for storing computer data and one or more application programs carrying out the various processes described herein, a graphical display device  144  for displaying information to a user, and a user input element for receiving user inputs to the PMCD. The user input element can be a keypad (not shown) or may be combined with the graphical display device  144  if a touch screen display is used for such purpose. The PMCD  118  also includes an imaging device  146  (e.g. a camera) that is capable of scanning a barcode, a light emitting device  148  (such as an LED used for camera flash and/or illumination). Finally, the PMCD can include one or more radio frequency communication hardware entities  150  which facilitate radio frequency communications as described herein. Exemplary radio frequency communications protocols implemented by the PMCD  118  can include wireless cellular data communications and wireless network communications. The wireless network communications protocols can be implemented in accordance with various well-known standards such as IEEE 802.11, Bluetooth and Near Field Communication protocols. 
     According to one aspect of the inventive arrangements, the customer can purchase the article  112  using the PMCD  118  when the customer and PMCD  118  are present within the retail store facility  102 . To begin a purchase transaction, the retail transaction application is launched on the customer&#39;s PMCD  118 . The launch process can be started simply by performing a user software interaction, such as depressing a key on a keypad of the PMCD  118  or touching a button on a touch screen display of the PMCD  118 . Once launched, the retail transaction application can wait for a further user input indicating that the user wishes to complete a purchase transaction. 
     To begin the purchase of article  112 , a retail transaction application executing on the PMCD  118  facilitates an exchange of data by which the PMCD receives UPC and/or EPC information pertaining to the article  112 . For example, if a UPC tag is provided on the article  112  the PMCD can use an imager or camera provided as part of the PMCD  118  to optically scan a barcode  114  containing the UPC information. 
     In the barcode scenario, the article  112  has a barcode  114  attached to an exposed surface thereof. The term “barcode”, as used herein, refers to a pattern or symbol that contains embedded data. Barcodes may include, for example, one-dimensional barcodes, two dimensional barcodes (such as matrix codes, Quick Response (“QR”) codes, Aztec codes and the like), or three-dimensional bar codes. The embedded data can include, but is not limited to, a unique identifier of the article  112 . The barcode  114  is read by using an imager/camera (not shown in  FIG. 1 ) that is provided as part of the PMCD. Barcode scanners/reader software is well known in the art and therefore will not be described here in detail. In an alternative embodiment, the article information such as an EPC or UPC can be communicated from the article  112  to the PMCD  118  by means other than optical scanning. For example, a wireless communication, such as a Near Field Communication (“NFC”), could be used for this purpose. 
     After the customer has used the PMCD  118  to acquire the UPC or EPC information they may optionally manually input additional data into the retail transaction application to facilitate a purchase transaction. Such additional data can include any information that is useful for purchasing the article  112 . Alternatively, the user may use a keypad or touchscreen of the PMCD to manually input the UPC or EPC information. 
     After the customer has used the PMCD to obtain the article information for an article  12  that they wish to purchase, payment information is input into the retail transaction application of the PMCD  118 . The payment information can include, but is not limited to, a customer loyalty code, payment card information, and/or payment account information. The payment information can accessed from a data store (not shown) that is associated with the PMCD. Alternatively, the payment information can be input to the PMCD using suitable automated means. Exemplary methods can involve the use of optical scanning devices, cameras, imagers, barcode readers and electronic card readers without limitation. Electronic card readers and barcode readers are well known in the art, and therefore will not be described herein. Any known or to be known automated system for acquiring the payment information can be used without limitation. The payment information can alternatively or additionally be obtained from a remote data store based on a customer identifier or account identifier. In this case, the payment information can be retrieved from stored data associated with a previous sale of an article to the customer. 
     Upon obtaining the payment information, the PMCD  118  automatically performs operations for establishing a retail transaction session with the Retail Transaction System (“RTS”)  124 . RTS  124  is part of a corporate facility  122 . The RTS  124  can be located at the retail store facility  102  or can be at a location that is remote from the retail store facility  102 . 
     The retail transaction session can involve communicating the article information and payment information from the PMCD  118  to the RTS  124  via a data network  120 . The data network can be comprised of a single network or a plurality of interconnected computer data networks. For example, in some scenarios the data network  120  can be comprised of a local wireless computer data network maintained within the retail store facility  102 . But in other scenarios, the data network  120  can include a wireless cellular data network (not shown). The data network  120  can also comprise a network of networks, such as the Internet. The retail transaction can further involve completing a purchase transaction by the RTS  124 ; and communicating a response message from the RTS  124  to the PMCD  118  indicating that the article  112  has been successfully or unsuccessfully purchased. The purchase transaction can involve using an authorized payment system, such as a bank Automatic Clearing House (“ACH”) payment system, a credit/debit card authorization system, or a third party system (e.g., PayPal®, SolidTrust Pay® or Google Wallet®). 
     The purchase transaction can be completed by the RTS  124  using the article information and payment information. In this regard, such information may be received by a computing device  126  of the RTS  124  and forwarded thereby to a sub-system of a private network  128  (e.g., an Intranet). For example, the article information and purchase information can also be forwarded to and processed by one or more transaction sub-systems  130  to complete a purchase transaction. When the purchase transaction is completed, a message is generated and sent to the PMCD  118  indicating whether the article  112  has been successfully or unsuccessfully purchased. 
     If the article  112  has been successfully purchased, then a security tag detaching/deactivation process can be started automatically by the RTS  124  or by the PMCD  118 . Alternatively, the user (not shown in  FIG. 1 ) can start the security tag detaching/deactivation process by performing a user-software interaction using a keyboard or touchscreen of the PMCD  118 . In all three scenarios, the PMCD  118  is used to access security tag information which is available on or in the security tag  106 . According to one aspect, the security tag information can be contained in a security tag barcode  108  which is disposed on an exterior housing of the security tag  106 . The security tag barcode  108  can be any visible pattern or symbol that contains embedded data. Barcodes may include, for example, one-dimensional barcodes, two dimensional barcodes (such as matrix codes, Quick Response (“QR”) codes, Aztec codes and the like), or three-dimensional bar codes. 
     Referring now to  FIG. 2 , there is shown an exemplary security tag  106  with a wire loop  203  that is attached at one end to the housing of the security tag and terminated at an opposing end by a pin  202 . A barcode is disposed on an exterior of the housing  204  of the security tag. The pin  202  is secured within the housing  204  by a releasable latching mechanism which will be described below in further detail. Although not shown in  FIG. 2 , the wire loop  203  can be extended through a portion of an article  112  so that the security tag is fixed to the article  112  in a manner that is well known in the art. It should be understood that there are many different types of security tags with many different mechanisms to facilitate their attachment to a particular article. Accordingly, the particular security tag arrangement shown in  FIG. 2  is provided merely to facilitate an understanding of the invention. The inventive arrangements described herein can be used with any form of security tag where the tag is attached to an article by means of a releasable pin or other type of releasable element that is held in place by a latching mechanism. 
     Referring now to  FIG. 3 , the security tag  106  can include a processing element  302  to facilitate certain functions relating to security tag detachment operations. The processing element  302  is advantageously selected to be a device with very low power consumption so as to minimize power consumption from an onboard power source  312 , such as a battery. Accordingly, the processing element  302  can be implemented as a microprocessor, microcontroller, Field Programmable Gate Array or any other suitable processing element capable of performing the processing functions described herein. The security tag  106  also includes an optical sensor  304  arranged for detecting the encoded optical sequence (“unlock code”) produced by the PMCD  118  and communicating such information to the processing element. The security tag  106  also includes a latch  307  which includes latch release mechanism  308 . The latch release mechanism is controlled by the processing element  302  for latching and unlatching pin  202 . Finally, the security tag  106  can include an optical emitter, such as a Light Emitting Diode (LED), and an audio annunciator  310 , both of which are under the control of the processing element  302 . 
     As is well known a camera or imaging device is often provided as part of a PMCD  118 . Such camera or imaging device can be used to read the security tag barcode  108 . The retail transaction application in the PMCD  118  advantageously includes software or firmware suitable to interpret the barcode  108  and thereby extract the security tag information. After the customer has used the PMCD  118  to scan the security tag barcode and obtain the security tag information, the customer places the PMCD  118  near the security tag  106 . The retail transaction application in the PMCD  118  uses the security tag information and a computational algorithm (such as public key encryption) to compute an encrypted unlock code for the security tag. The encryption method used would be adjusted according to the requirements of the application and the practical data transmission limits of an optical link between the mobile device and the tag as described below. 
     Once the unlock code is computed, the retail transaction application generates an encoded optical sequence (“unlock code”) using hardware elements available in the PMCD. For example, the touch screen display of the mobile device can be used for this purpose by alternating a portion of the screen area using the color white and black to form a sequential optical pattern. Alternatively, a camera flash device incorporated into the PMCD  118  can be used to form the alternating optical pattern or sequence during which the flash device is sequentially turned on and off in accordance with a pattern that corresponds to the unlock code. Of course, the invention is not limited in this regard and other light emitting features or attachments provided as part of a PMCD  118  can be modulated by software on the mobile device to produce the desired optical pattern. Regardless of the particular hardware element in the PMCD  118  that is used to form the optical pattern, it is advantageous that the optical sequence should be encoded using a standard serial communication methods and/or symbols to assure accurate and reliable decoding by the anti-theft tag as hereinafter described. 
     As shown in  FIG. 4 , the processing element  302  in the security tag uses the optical sensor  304  to receive the encoded optical sequence  406  that has been generated by the PMCD  118 . If the processing element  302  determines that the encoded optical sequence comprises a valid unlock code, then the processing element causes the latch release mechanism  308  to release a shank  402  of pin  202  that is locked within a cooperating aperture formed in the housing  204  of the security tag  106 . For example this can be accomplished by causing a tooth associated with the latch  307  to disengage from one of several grooves  404  disposed in the shank  402 . Once the security tag&#39;s latch release mechanism is activated, the pin  202  can be removed from the tag body  204  as shown in  FIG. 4 . Removal of the pin in this manner facilitates detachment of the security tag  106  by the customer from an article  112 . 
     The security tag  106  can be configured such that a customer is notified by a suitable audio or visual signal when the latch release mechanism has been activated using the above-described process. For example, the audio annunciator  310  and/or optical emitter  306  can be used for this purpose. The processing element  302  activates the audio annunciator  310  and/or optical emitter  306  when a correct unlock code has been received and/or the latch release mechanism has been activated so as to visually and/or audibly notify the customer that the tag can be removed. 
     After the latch release mechanism has been activated, the security tag  106  can remain in this state for a period of time that allows the tag to be removed from an article, after which the latch release mechanism  308  is deactivated and the latch  307  reverts back to a locked state. The purchase transaction and security tag detaching process described herein is repeated for each item in the transaction. Once the security tag  106  has been removed from article  112 , the customer  140  can carry the article  112  through the surveillance zone without setting off the alarm. 
     A barcode disposed on the exterior housing of the security tag is on method to facilitate access to the security tag information necessary for computing an unlock code. However, in some scenarios the security tag  106  may comprise an NFC enabled transceiver device  314 . As is known, an NFC communication occurs between NFC enabled devices over a relatively small distance (e.g., N centimeters or N inches, where N is an integer such as twelve). In such a scenario, the NFC communication may be established by touching the PMCD to the security tag  106 , or by bringing them in close proximity such that an inductive coupling occurs between inductive circuits thereof. In such a scenario, the PMCD can also include an NFC transceiver as part of the radio frequency communication hardware entities  150 . The NFC transceiver will facilitate an NFC communication session so as to request and obtain the security tag information needed to determine a suitable unlock code. 
     In some scenarios, the NFC operates at 13.56 MHz and at data rates ranging from 120 kilobits per second to 848 kilobits per second. The NFC may be achieved using NFC transceivers configured to enable contactless communication at 13.56 MHz. NFC transceivers are well known in the art, and therefore will not be described in detail herein. Any known or to be known NFC transceivers can be used herein without limitation. 
     Optical communication of the unlock code is advantageous as it facilitates a relatively simple inexpensive receiving element in the security tag  106  and leverages existing hardware elements in the PMCD  118 . However, the inventive arrangements are not necessarily limited to such optical communications methods. For example, in some embodiments, the optical sensor  304  can be replaced or supplemented by a radio frequency receiving element for receiving radio frequency signals  408  communicated by the PMCD  118 . A near field communication (NFC) type receiver could be used for this purpose if the PMCD  118  is equipped with an NFC transceiver as part of the radio frequency communication hardware entities  150 . The radio frequency signals would comprise a coded message containing the unlock code. In other respects, the security tag with an NFC capability would function in a manner similar to the optical arrangement described herein. 
     Further, although the inventive arrangements have been described thus far with respect to unlocking and removal of a security tag, it should be appreciated that the invention is not limited in this regard. Instead, the approach described herein can also be utilized to deactivate an EAS element of a security tag attached to an article. Also, it should be understood that although the various embodiments have been described with respect to a retail security anti-theft environment, the invention is not limited in this regard. Instead, the security tag detachment or EAS tag deactivation as described herein can more broadly be understood as pertaining to any type of inventory control scenario where the removal of articles or inventory items from a controlled area is desired. In such a scenario, the right or authorization to remove the inventory article from the controlled area might not necessarily involve a purchase transaction. Instead, the permission to right remove the inventory item or article from the controlled area can be established based on some basis other than a payment transaction. In such scenarios, an authorization transaction can be performed in place of the payment transaction. The authorization transaction can comprise any suitable transaction in which credentials or means other than payment are used as a basis for permitting article removal from a controlled area. 
     Referring now to  FIGS. 5A-5C , there is provided a flow diagram of an exemplary method  500  for security tag detachment or deactivation authorization described herein. As shown in  FIG. 5A , method  500  begins with step  501  and continues with step  502  where a purchase transaction (or other similar permission based transaction) is initiated using a PMCD (e.g., PMCD  118  of  FIG. 1 ). Techniques for initiating such a transaction are well known in the art, and therefore will not be described herein. After completing step  502 , step  504  is performed where the PMCD is used to obtain a UPC and/or an EPC for at least one product to be purchased. The UPC uniquely identifies a type of product. The EPC uniquely identifies a particular product. The UPC and/or EPC can be obtained using one or more scanning technologies as is known. The scanning technologies include, but are not limited to NFC technology and/or barcode technology. 
     The UPC and/or EPC is then communicated to a purchase sub-system (e.g., transaction sub-system  130  of  FIG. 1 ) to facilitate the retrieval of product information therefrom, as shown by step  506 . In this regard, the purchase sub-system may comprise or have access to a remote datastore in which product information was pre-stored. The product information includes, but is not limited to, product descriptions and purchase prices. The purchase sub-system then uses the UPC and/or EPC to obtain any associated product description and pricing information from the remote datastore, as shown by step  508 . The product description and pricing information is communicated in step  510  to the PMCD so that it can be displayed to the user thereof. 
     At this time, a decision step  512  is performed to determine whether a UPC and/or EPC has (have) been obtained for each product that is to be purchased. If a UPC and/or EPC has(have) not been obtained for each product that is to be purchased [ 512 :NO], then method  500  returns to step  504 . In contrast, if the UPC and/or EPC has(have) been obtained for each product that is to be purchased [ 512 :YES], method  500  continues with step  514 . Step  514  involves completing the purchase transaction for the product(s) associated with the UPC(s) and/or EPC(s) previously obtained. If the purchase transaction was not successful [ 516 :NO], then step  518  is performed where the purchase transaction is canceled. If the purchase transaction was successful [ 516 :YES], then step  520  is performed to facilitate a security tag detachment/deactivation process. 
     Step  520  involves communicating from the transaction sub-system to the PMCD a tag detachment or deactivation authorization code which enables the PMCD to perform or complete a security tag detachment or deactivation with respect to one or more purchased items. One authorization code can be provided for each UPC and/or EPC corresponding to an article that has been successfully purchased. According to one aspect, the authorization code is an unlock code for a security tag that can be used by the PMCD to generate an encrypted unlock code which is communicated to the security tag as described below. However, the invention is not limited in this regard and the authorization code can be a simple acknowledgment that the PMCD is now authorized to generate or compute an unlock code. In such a scenario, a standard unlock code could be used for all security tags, but such unlock code will be encrypted in accordance with a public key information which is obtained directly from the security tag. The security tag can then use a private key to decrypt the unlock code to determine if it is valid. 
     In some embodiments, the authorization code for each security tag can be provided in association with a particular UPC and/or EPC to identify the particular purchased article for which authorization for tag removal/deactivation has been received. Step  520  is performed so that the PMCD has knowledge of the particular articles which (a) have been successfully purchased and (b) have security tags that need to be deactivated or detached therefrom. It is also performed as a security measure so as to selectively limit the circumstances and conditions under which the PMCD can facilitate detachment and/or deactivation of a security tag. 
     Upon completing step  520 , method  500  continues with step  524  of  FIG. 5B . As shown in  FIG. 5B , step  524  involves receiving the authorization code at the PMCD from the transaction sub-system. Next in optional step  526 , a notification is output from the PMCD. The notification indicates that the authorization code has been successfully received from the transaction sub-system and/or that the user is now authorized to use the PMCD to perform security tag detachment/deactivation actions. In response to the notification, the user optionally initiates the security tag detachment/deactivation in step  528 . For example, the process can be initiated upon receiving a user input on the PMCD indicating that the user is ready to begin the security tag detachment/deactivation process. 
     In a next step  530 , the user is prompted use the PMCD to obtain security tag information from the security tag by moving the PMCD closer to the security tag. The user can also be prompted to use an imager that is integrated into the PMCD and/or NFC hardware elements provided in the NFC to obtain the security tag information. If an imager is used, this process can involve imaging and then decoding a barcode disposed on the exterior of the security tag housing. If NFC hardware elements are available in the PMCD and security tag, then this process can involve using such hardware elements in the PMCD to interrogate the security tag for the security tag information. The process can further involve using NFC to receive such information from the security tag. Once received, the security tag information is used by the PMCD at  532  to compute an encrypted unlock code. The encrypted unlock code can be unique to the particular security tag for which the information has been obtained. In the case of a security tag to be detached, the encrypted unlock code will cause unlatching or unlocking of the security tag to facilitate detachment of the tag from an article when the code is received in the security tag. In the case of a security tag to be deactivated, the encrypted unlock code will cause the security tag to be inactivated. 
     At  538  the encrypted unlock code is communicated to the security tag using an optical communication protocol or NFC type communication protocol. Thereafter, at  540  the security tag performs operations to determine if a correct unlock code has been received. If the correct unlock code has not been received [ 542 :NO], then steps  544 - 546  are performed. These steps involve: denying the detachment/deactivation of the security tag; and outputting a message to the user indicating that the security tag&#39;s detachment/deactivation has been denied. Subsequently, step  548  is performed where method  500  ends or returns to step  528 . 
     If the unlock code does match the unlock code stored in firmware of the security tag [ 242 :YES], then method  500  continues with steps  550 - 554  of  FIG. 5C . These steps involve activating the latch release mechanism at  550  to allow the tag to be detached. Alternatively, in the case where the security tag is being deactivated, the unlock code is used to cause deactivating of the security tag. In step  552 , the user can optionally be notified that the security tag has been unlatched or deactivated. This can be accomplished by using the tag to signal with an audio annunciator or an optical emitter. In some scenarios, the PMCD can configured detect such notification and will respond by updating a list of purchased articles on the PMCD to reflect that the security tag has been detached or deactivated. 
     Upon completing step  554 , a decision step  556  is performed to determine whether the security tags for all of the purchased products have been detached/deactivated. If all of the security tags have not been detached/deactivated [ 556 :NO], then step  558  is performed where method  500  returns to step  528 . In contrast, if all of the security tags have been detached/deactivated [ 556 :YES], then step  560  is performed where method  500  ends or other processing is performed. 
     The transmission of the encrypted unlock code between the PMCD and the security tag will advantageously involve use of a public key encryption scheme to prevent security attacks (such as thieves attempting to capture unlock codes as they are transmitted to the security tag, then using the unlock code to remove other security tags). Asymmetric key encryption can be used to allow the application software in the PMCD to encrypt valid unlock codes where only the security tag which holds the private key (in its firmware) can decrypt the unlock command. According to one aspect, the security tag information obtained by the PMCD from the security tag&#39;s barcode is that tag&#39;s public key. Accordingly, the PMCD obtains the public key by reading the barcode identifier on the security tag. The security of this system relies on keeping the private key of each security tag secret. This would be accomplished by embedding the tag&#39;s private key securely in the firmware of the tag. 
     It is conceivable that a person utilizing the inventive arrangements could seek to circumvent certain theft prevention features of an EAS system. For example, a person could conceivably purchase a low cost item in order to obtain a “detach” authorization from a transaction system (e.g. retail transaction system  124 ), and then use this authorization to detach a tag attached to a higher priced item. There are several options for preventing such a scenario. 
     According to one aspect, when the security tag is applied to an inventory item by an agent or employee of the controlled facility (e.g. retail store), a scanning process would be performed. The scanning process would acquire the UPC/EPC data for the item and the security tag information for the particular security tag that is attached to the item. This information is then stored in a database  132  in a manner so as to associate the security tag information to the UPC/EPC data for the item to which the tag is attached. 
     Thereafter, when a customer wishes to remove an item from a controlled area (e.g. a retail store) they will use their PMCD to communicate the security tag information to the retail transaction system. This action can be performed as part of the purchase transaction and/or as part of the tag detachment/disable operations. 
     Once the security tag information has been received from the PMCD, the transaction system could check the security tag information against the corresponding UPC/EPC stored in the database. The database records will show the UPC/EPC of the item to which the security tag was attached. This particular UPC/EPC linked to the security tag information can then be compared to a list of the purchased items. If the UPC/EPC that is linked to the security tag information does correspond to one of the purchased items, then the transaction system will issue an authorization to the PMCD to facilitate detachment and/or disabling the security tag. As a further security measure, when the authorization code is communicated from the PMCD to the security tag, the public key information from the security tag can be used to encrypt the authorization. 
     According to a further embodiment, each security tag can have a unique authorization code for detaching and/or disabling the tag. The unique authorization code can be associated with or linked to the security tag information in the transaction system database. When a customer wishes to remove an item from a controlled area (e.g. a retail store) they will use their PMCD to communicate the security tag information to the retail transaction system (or inventory transaction system). This action can be performed as part of the purchase transaction and/or as part of the tag detachment operations. If a transaction is successfully executed, the transaction system will provide an authorization code to unlatch and/or disable the security tag. The authorization code in such scenario will be unique to the particular tag that is attached to the item. More particularly, the transaction system can access the database to associate the security tag information with a corresponding specific authorization code that is needed to unlock the particular security tag. The transaction system can also use this opportunity to verify that the security tag information which has been received from the PMCD in fact corresponds to a security tag that has been attached to an item having the particular UPC/EPC. As a further security measure, when the authorization code is communicated from the PMCD to the security tag, the public key information from the security tag can be used to encrypt the authorization. 
     All of the apparatus, methods, and algorithms disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the invention has been described in terms of preferred embodiments, it will be apparent to those having ordinary skill in the art that variations may be applied to the apparatus, methods and sequence of steps of the method without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain components may be added to, combined with, or substituted for the components described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those having ordinary skill in the art are deemed to be within the spirit, scope and concept of the invention as defined. 
     The features and functions disclosed above, as well as alternatives, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements may be made by those skilled in the art, each of which is also intended to be encompassed by the disclosed embodiments.