WO2011117473A1

WO2011117473A1 - A point of sales system and a method of using the same

Info

Publication number: WO2011117473A1
Application number: PCT/FI2011/050255
Authority: WO
Inventors: Samuli STRÖMBERG
Original assignee: UPM Raflatac Oy
Current assignee: UPM Raflatac Oy
Priority date: 2010-03-26
Filing date: 2011-03-28
Publication date: 2011-09-29
Anticipated expiration: 2012-09-26
Also published as: FI20105312A0; FI123468B; FI20105312L

Abstract

A method of using a point of sales system (500), said point of sales system (500) comprises a reader (210), a payment unit (300), a control unit (400), and a transmitter (220), said method comprising: - reading first information (INF1) stored in a first radio frequency identification tag (50a) by said reader (210), - identifying an item (100) based on the first information (INF1), - confirming a payment associated with said first information (INF1) by said payment unit (300), - enabling sending second information (INF2) by said control unit (400) when the payment has been confirmed, and - sending the second information (INF2) to a second radio frequency identification tag (50b) by said transmitter (220).

Description

A POINT OF SALES SYSTEM AN D A METHOD OF USING THE SAME

FIELD OF THE INVENTION

The present invention relates to point of sales system and to a method for using the point of sales system.

BACKG ROUND

A European patent EP 1 372097 discloses a point of sales (POS) system, which is arranged to print advertising information on a receipt.

SUMMARY

An object of the present invention is to provide a point of sales (POS) system. An object of the present invention is to provide a method for using a point of sales (POS) system.

According to a first aspect of the invention, there is provided a method according to claim 1 .

According to a second aspect of the invention, there is provided a system according to claim 7.

A point of sales system (500) may comprise a reader (21 0), a payment unit (300), a control unit (400), and a transmitter (220). A method for using the point of sales system (500) may comprise:

- reading first information (INF1 ) stored in a first radio frequency identification tag (50a) by said reader (21 0),

- identifying an item (1 00) based on the first information (INF1 ),

- confirming a payment associated with said first information (INF1 ) by said payment unit (300), - enabling sending second information (INF2) by said control unit (400) when the payment has been confirmed, and

- sending the second information (INF2) to a second radio frequency identification tag (50b) by said transmitter (220).

The system 500 may be located e.g. in a store. Several similar or different tagged items 1 00 may be for sale in the store.

The first information INF1 may comprise e.g. identification data, which allows identification of the item, and associating the item with a price.

The first information INF1 may also be used in other manner e.g. when counting a plurality of items remotely and substantially simultaneously. This may be useful e.g. when making an inventory in a store or for electronic article surveillance (EAS, anti-theft system). Therefore it may be advantageous to send the first information by far field communication.

The second information INF2 sent to the second tag is stored in a memory of the second tag for subsequent reading. The second information INF2 may be later used to prove e.g. that the particular item in question has been sold from a particular store. The second information IN F2 may be used e.g. for preventing refund of a payment when a customer tries to return an item 1 00 to a store, which has been purchased from a different store. Refund may be prevented when a customer tries to return an item, which has not been purchased from a store belonging to a group of authorized (predetermined) stores.

The second information INF2 may be associated with a substantial economical value. Therefore, storing of the second information INF2 to the second portion 20 may be disabled until the payment associated with the item 1 00 has actually been confirmed.

The first information may be stored in a first tag attached to an item, and the second information may be stored in a second tag attached to said item. The second tag may be attached to an item after confirmation of the payment. The second information INF2 may be associated e.g. with a temporally limited advertising campaign.

A large store may contain thousands or even millions of individual items. A considerable fraction of those items may be tagged with first RFID tags before they are sold. A first RFID tag may be a relatively simple and low-cost device. In particular, the first RFID tag may be a cheap disposable device.

In an embodiment, the first information obtained from the first RFID tag needs to comprise only identification data. On the other hand, the second RFID tag may be more expensive. A second RFID tag may be e.g. arranged to withstand wear and/or other demanding environmental conditions such as water, detergents and/or high temperatures. The second RFI D tag may be manufactured to endure substantially during the whole expected lifetime of the sold item.

For example, a second RFID tag attached to a garment after confirmation of the payment may be arranged to withstand washing in a washing machine.

A second RFID tag may comprise e.g. a large memory for containing large amounts of data. A second RFID tag may comprise a hardware encryption unit for preventing counterfeiting of stored information. Considerable savings may be expected when the second tag is attached only to a product, which has truly been sold.

The reading range when using the second RFID tag may be substantially smaller than when using the first RFI D tag, therefore, the second tag may have a smaller antenna. The second tag may be substantially smaller than the first tag. BRIEF DESCRIPTION OF THE DRAWINGS In the following examples, the embodiments of the invention will be described in more detail with reference to the appended drawings, in which

Fig. 1 shows a point of sales (POS) system, and an item positioned in the vicinity of an RFID transmitter of the point of sales system,

Fig. 2 shows subsequent reading of information from a tag attached to said item, shows an RFI D tag attached to the item, shows method steps for reading first information from the tag attached to the item, and for storing the second information, shows a point of sales (POS) system comprising a tag dispenser, shows, in a three dimensional view, an RFID tag, shows, in a three dimensional view, an RFID tag comprising a dipole antenna, and shows, in a three dimensional view, an RFID tag comprising an inductive antenna.

DETAILED DESCRI PTION Referring to Fig. 1 , a first radio frequency identification (RFID) tag 50a may be attached to an item 1 00. The first tag 50a may comprise information INF1 regarding the item. In particular, the first tag 50a may comprise information INF1 which identifies the item 1 00.

A point of sales (POS) system 500 may comprise a reader 21 0 for reading first information IN F1 from the portion 1 0 of the first radio frequency identification (RFID) tag. The system 500 may comprise a transmitter (220) for sending second information IN F2 to a portion 20 of a second radio frequency identification tag 50b. The portion 1 0 may also be called as a first data area. The portion 20 may also be called as a second data area.

The system 500 may comprise a payment unit 300 for confirming payments. The system 500 may comprise a control unit 400 for controlling the operation of the system 500. The system 500 may comprise a memory MEM1 for storing e.g. price information. The memory MEM1 may also be an external database. A point of sales terminal may comprise the reader 21 0, the transmitter 220, and the payment unit 300.

Also a single tag 50 may comprise the first portion 1 0 and the second portion 20 (See Fig. 3). The tag 50 may be attached to the item 1 00.

Alternatively, the first tag portion 1 0 and the second tag portion 20 may be located in separate tags 50a, 50b (see Fig. 1 ).

Radio frequency identification tags 50, 50a, 50b may be attached or otherwise associated with items 1 00 in order to identify the items and/or to track movements of the items. Information stored in the tags 50, 50a, 50b may be read in a wireless manner by using a portable (movable) reader 201 or a stationary reader 21 0. The radio frequency identification tag 50, 50a, 50b comprises a transponder, which is coupled to an antenna. The tag 50, 50a, 50b may respond to an interrogation signal by transmitting a response. The response may contain first information INF1 , which e.g. specifies an identification number of the item 100 attached to the tag 50, 50a, 50b. Unobstructed line of sight between the tag 50, 50a, 50b and the reader 210, 600 is not necessary (a reader 600 is shown in Fig. 2). Typically, the orientation of the item 100 with respect to the reader 210, 600 is not critical. Several items 100 may be remotely identified substantially simultaneously.

The information INF1 stored in the tag 50, 50a may be remotely read by a reader 21 0. The maximum reading distance between the tag 50, 50a and the reader 210 may be e.g. in the range of 5 cm to 3 m, depending on the applied frequency band and communication protocol.

The first information INF1 may comprise e.g. identification data. The identification data may specify e.g. the type of the item 100, a manufacturing batch of said item, and/or a unique serial number of said item.

In particular, the information INF1 may comprise an electronic item code (EPC). A unique electronic item code assigned to an item may be stored in the tag 50a as a binary number of e.g. 64 or 96 bits long. In particular, a bit string may include information regarding an item such as its manufacturer, type of the item, serial number, for example.

The first information INF1 may be communicated by far field communication, and the second information INF2 may be communicated by near field communication (NFC).

The first information INF1 may be communicated e.g. according to the standard EPC Gen2, according to the standard ISO 18000-4, the standard ISO 18000-6, or the standard ISO 18000-7. The second information INF2 may be communicated e.g. according to the standard ISO 15693, or the standard ISO 14443. In particular, an end-user (customer) of the purchased item 1 00 may use a reader 600, which is arranged to communicate according to a near field communication protocol (NFC), but not according to a far- field communication protocol. A NFC reader 600 may be implemented e.g. in a mobile phone or in a portable computer device.

However, the first information INF1 and the second information INF2 may also be communicated according to the same standard or according to the same protocol.

The second information INF2 may be associated with a substantial economical value. Therefore, storing of the second information INF2 to the second portion 20 may be disabled until the payment associated with the item 1 00 has been actually confirmed.

The system 500 may comprise a control unit 400, which is configured to enable transmitting the second information INF2 only after a payment associated with the item 1 00 has been confirmed.

The system may comprise a payment unit 300 for confirming payments. The payment unit 300 may comprise a display 390 for visually displaying price information, and a user interface 380 (e.g. a keypad) for receiving commands.

The payment may be confirmed in different ways.

The client may confirm the payment himself by bringing a payment card 700 in the vicinity of the card reader 370 or by bringing the payment card 700 in contact with the card reader 370.

In certain payment systems, the client may additionally need to enter a confidential personal identity number (PIN number) before the payment is confirmed. In certain payment systems, the client may need to confirm the payment by pressing a sensor plate with his finger in order to authenticate his identity via fingerprint detection. When using the payment card 700, the confirmation of the payment is recorded in a database of the POS system.

The payment card 700 may be a prepaid payment card, a credit card, a bank card. In case of a prepaid card, the price of the item 100 may be transferred from an internal memory of the card 700 to an account of the store. In other words, a number stored in the card 700 may be subtracted by an amount corresponding to the first information INF1 , and said amount may be added to a register in the POS system 500. In case of a credit card or a bank card, the payment card 700 may specify a bank account or a credit account from which the price is subtracted.

In certain payment systems, it is not necessary to present a payment card, because the personality of the client may be otherwise reliably associated with a bank account or a credit account. For example, the client may simultaneously authenticate his identity and confirm the payment by fingerprint detection or by entering a personal identity number (PIN number) via the interface 380.

The salesperson may visually identify the personality of the client, and the salesperson may confirm the payment via the interface 380. Typically, the client is also requested to write his signature on a paper, which indicates the date and the amount paid. However, in technical sense, writing a signature on paper is typically a legal authorization, not a confirmation of payment.

In an embodiment, the second information INF2 may specify an amount of money so that the second portion 20 may be subsequently used as a cash voucher e.g. for buying other items or services. In that case, the corresponding amount may be subtracted from a bank account of the shopkeeper when the second information INF2 is stored in the second portion 20 of the tag 50, 50b. The payment unit 300 may comprise a card reader 370 for reading information INF3 from a payment card 700. The information INF3 sent from the payment card 700 to the payment unit 300 may specify e.g. an identification code associated with the payment card 700.

Traditionally, the client may also give money (banknote, coins) to a salesperson in order to make the payment. If the amount of money forwarded to the salesperson matches with the price corresponding to the first information INF1 , the salesperson may technically confirm the payment via the interface 380, e.g. by pushing a button of the keypad 380.

The confirmation of the payment may be recorded in a database of the POS system. This reduces the risk that a dishonest salesperson might steal the money.

Referring to Fig. 2, the second information INF2 stored in the second portion 20 may be read (retrieved) at a later stage by a reader 600.

A shopkeeper or an end-user of the item 1 00 (i.e. a customer) may use a reader 600 for obtaining the second information INF2. A reader 600 may be implemented e.g. in a mobile phone or in a portable computer device.

The second information INF2 may specify e.g. that the item 1 00 in question has been sold from a particular store. The second information INF2 may be utilized e.g. for preventing refund of a payment when a customer tries to return an item 1 00, which has been purchased from a different store. The second information INF2 may be utilized e.g. for preventing refund when a thief attempts to return an item stolen from the store, and tries to get the price refunded.

The second information INF2 may specify e.g. the amount of the payment that has been made. The second information INF2 may e.g. specify an amount to be refunded when an item is returned to the store.

The second information INF2 may specify e.g. the date of confirmation of the payment.

The second information INF2 may be used e.g. for determining whether a warranty period has expired. The second information INF2 may comprise e.g. a warranty certificate.

The second information INF2 may contain an internet link to a user manual for the product, or to a corresponding user support site in the internet, or to a user discussion forum in the internet. The manual and/or the support/forum site may be specific for the state or territory where the item was purchased. The second information INF2 may contain an internet link to an official importer/retailer. The second information INF2 may contain an internet link to a discussion forum in a predetermined language. The second information INF2 stored in the tag 50, 50b may entitle to a membership in a club. For example buying a kitchen appliance may subsequently entitle the purchaser to a membership in a culinary club, which in turn provides access to a recipe library and entitles the purchaser to buy accessories at a discount price.

The second information INF2 may comprise e.g. a password, which allows the client to download a computer game via internet and/or to use a computer game. The second information INF2 may comprise an activation code (password) for activating a computer program downloaded from the internet. The second information INF2 may comprise a password which allows access to an internet magazine.

The second information INF2 may be used to allow e.g. a free entry to a nightclub during a limited period after purchase of the item 1 00. The second information INF2 may comprise advertising information. A reader 600 may be incorporated e.g. in a mobile phone or computer of a customer so that the customer is able to read at least a part of the second information INF2 by himself.

The second information INF2 may comprise an electronic receipt.

It is known that the paper printer of a conventional cash register may be arranged to print a receipt. According to the invention, the paper printer may be replaced with an RFID transmitter 220, or an RFID transmitter 220 may be used in addition to the paper printer. The second information INF2 sent to the second portion 20 of the tag 50, 50b may comprise the receipt in electronic form. The transmitter 220 may be arranged to receive electric printer data, and convert the electric printer data to a radio frequency signal, which comprises the second information INF2.

In particular, a conventional receipt printer attached to a conventional cash register may directly be replaced with the RFID transmitter 220 with minimum modifications. In particular, the transmitter 220 may communicate with the control unit 400 according to a communication protocol or standard of a conventional (paper) receipt printer.

An RFID tag 50, 50b comprising the second portion 20 may be permanently attached to the item. This minimizes the risk of misplacing or losing the receipt after purchase. In contrast, a traditional paper receipt is typically rather large and may easily get lost after purchase. In particular, text of a receipt printed by a thermal printer on heat- sensitive paper typically disappears in time.

It is known that the paper printer of a conventional cash register may be arranged to print a warranty certificate when the item is purchased. The paper printer may be replaced with the RFI D transmitter 220 in order to store the warranty certificate to the second portion 20 of the tag 50, 50b in electronic form. If the item 1 00 does not already have a tag 50, which comprises the second portion 20, a second tag 50b comprising the second portion 20 may be provided by a tag dispenser 280 (See Fig.5). The tag dispenser 280 may be attached to the The RFID transmitter 220.

The second information INF2 associated with each item 1 00 may unique, i.e. the second information INF2 may different even when the customer buys several identical products. In particular, when the second information INF2 comprises a warranty certificate, each warranty certificate should be unambiguously associated with only one item 1 00.

In another embodiment, the same second information INF2 may be associated with several items 1 00. For example, the same advertising information may be stored in the tags 50, 50b of several different products.

Referring to Fig. 3, a single tag 50 may comprise the tag portions 1 0, 20. However, when dealing with a large number of items, the overall costs for using a single tag 50 may be higher than when using a first tag 50a and a separate second tag 50b.

Fig. 4 shows method steps for storing data into the second portion 20 of a tag 50, 50b.

In step 91 0, the item 1 00 may be identified by reading (retrieving) the first information INF1 stored in the first portion 1 0 of the tag 50, 50a.

In step 920, the control unit 400 may retrieve price information, which corresponds to the first information INF1 , from a memory MEM1 of the POS system 500. The memory MEM1 may also be an external database.

In step 930, the price information may be displayed to a user (salesperson) and/or to a customer. The price information may also be spelled out by a voice. The customer may accept the price and make a payment. In step 940, the payment is confirmed. In step 950, the control unit 400 may check whether the payment corresponding to the item 1 00 has been confirmed. Transmission of the second information INF2 may be disabled until the payment corresponding to the first information INF1 has been confirmed. In step 960, the control unit 400 may retrieve the second information INF2 from the memory MEM1 .

In step 970, the second information INF2 may be sent to the second tag portion 20 and stored in the second tag portion 20 of the tag 50, 50b.

Subsequently, the POS system 500 may optionally be arranged to check that the second information INF2 is validly stored in the portion 20. For example, the reader 21 0 or another additional reader of the POS system may be arranged to send a test interrogation signal, and to receive information INF2 sent from the tag 50, 50b in order to verify that INF2 was validly recorded.

A tag 50, 50a, 50b may comprise an electronic article surveillance (EAS) functionality in order to prevent theft of goods. The electronic article surveillance (EAS) functionality may be switched off in the optional step 980 after the payment has been confirmed.

In an optional step 990, the first information IN F1 stored in the first portion 1 0 may be erased (deleted). In other words, the first tag portion 1 0 may be "killed" after purchase.

At a later stage, in step 1 01 0, the second information INF2 stored in the second tag portion 20 may be read by the reader 600 (Fig. 2). The first information INF1 may be stored in a tag attached to an item. After confirmation of the purchase, the second information INF2 may be stored in the same tag (Fig. 3). Alternatively, a first tag 50a and a separate second tag 50b may be attached to an item. The first information INF1 may be stored in the first tag 50a before purchase. The second information INF2 may be stored in the second tag 50b after confirmation of the purchase. Referring to Fig. 5, the system 500 may comprise a tag dispenser 280 for providing tags 50b, which comprise the second information INF2. Thus, the first information INF1 may be stored in a first tag 50a attached to an item 1 00, and the second information INF2 may be stored in a second tag 50b, wherein the second tag 50b may be attached to the item 1 00 after purchase. The dispenser may be arranged to operate such that dispensing and/or storing is enabled only after confirmation of the purchase.

Referring to Fig. 6, a radio frequency identification tag 50 may comprise the first portion 1 0 and the second portion 20. The portions 1 0, 20 may be separate or they may be partially overlapping. The first portion 1 0 may also be called as a first data area. The second portion 20 may also be called as a second data area. Alternatively, referring to Fig. 7a, a first radio frequency identification tag 50a may comprise the first portion 1 0. Referring to Fig. 7b, a second radio frequency identification tag 50b may comprise the second portion 20. The first portion 1 0 may comprise a first transponder 1 1 coupled to a first antenna structure A1 , A2. The second portion may comprise a second transponder 21 coupled to a second antenna structure CA3.

The transponders 1 1 , 21 may be implemented on the same semiconductor chip 30. The chip 30 and the antennae A1 , A2, CA3 may be supported by a substrate 40. The substrate 90 may be e.g. paper, cardboard or plastic film.

Alternatively, the first transponder 1 1 may be implemented on a first semiconductor chip, and the second transponder 21 may be implemented on a second semiconductor chip.

SX, SY, and SZ refer to orthogonal directions. The reader 21 0 of the POS system 500 (Fig. 1 ) may be capable of sending an interrogation signal according to a communication protocol of the first transponder 1 1 . The first transponder 1 1 may transmit a response to the interrogation signal. A response transmitted by the first transponder 1 1 may comprise the first information INF1 .

A portable or stationary reader 600 (Fig. 2) may be capable of sending an interrogation signal according to a communication protocol of the second transponder 21 . The second transponder 21 may transmit a response to the interrogation signal. A response transmitted by the second transponder 21 may comprise second information INF2.

The transponders 1 1 , 21 may operate according to different protocols. The first transponder 1 1 may be connected to a dipole antenna A1 , A2. The second transponder 21 may be connected to an inductive antenna CA3. The antenna CA3 may be a coil.

Alternatively, the transponders 1 1 , 21 may operate according to the same protocol (i.e. far field communication or near field communication). For example, the first transponder 1 1 may be connected to a dipole antenna A1 , A2, and the second transponder 21 may be connected to a dipole antenna A1 , A2. For example, the first transponder 1 1 may be connected to an inductive antenna CA3, and the second transponder 21 may be connected to an inductive antenna CA3. An RFID tag may be an active device, which comprises a battery for providing operating power.

The tag 50, 50a, 50b may be a passive device, which is powered e.g. by electro-magnetic energy transmitted from the readers 210, 600. In particular, the combination of an antenna structure A1 , A2, CA3 and a radio frequency unit of the transponders 1 1 , 21 may be arranged to provide operating power for the transponders 1 1 , 21 by extracting energy of an in-coming electromagnetic signal.

The tag 50, 50a, 50b may also be a semi-passive tag (battery- assisted).

The antennae A1 , A2, CA3 may be implemented e.g. by printing electrically conductive material on the substrate 40, or by locally etching material away from a layer of electrically conductive material. The electrically conductive material may be e.g. copper or aluminium.

The total thickness of a tag 50, 50a, 50b (in the direction SZ) may be smaller than or equal to 1 mm. The tag 50, 50a, 50b may be flexible. The tag 50, 50a, 50b may further comprise an adhesive layer (not shown). The tag 50, 50a, 50b may further comprise a release layer, which protects the adhesive layer. The release layer can be removed before the tag 50, 50a, 50b is attached to the item 100 by the adhesive layer.

The tag 50, 50a, 50b may be attached or associated with an item 100. The item may be a product, e.g. a television, mobile phone, or a component of an automobile. The item may be a package containing an item, a package containing foodstuff, a package containing medicine, a package containing a chemical substance.

A point of sales terminal comprising the reader 210, the transmitter 220, and the payment unit 300 may be portable (movable). A portable reader 21 0 may be brought close to a tagged item such that the distance between the reader and the tag 50, 50a, 50b is smaller than the maximum reading distance. The point of sales terminal may communicate with the memory MEM1 via wireless communication (e.g. via Bluetooth or mobile telephone network). Thus, a salesperson may freely walk among potential customers without a need to return to a fixed location in order to confirm a payment.

Alternatively, a tagged item may be brought (moved) close to a stationary reader 21 0 such that the distance between the reader and the tag is smaller than the maximum reading distance.

In an embodiment, the customer may even use the point of sales terminal himself.

The interrogation signal sent by the reader 21 0, the response containing the first information INF1 , and the signal containing the second information INF2 may be sent as electromagnetic waves, e.g. in the frequency range 1 00 kHz to 1 0 GHz.

In an embodiment, the first information INF1 may be transmitted by using a far field communication protocol, and the second information INF2 may be transmitted by using a near field communication (NFC) protocol.

In particular, the first information INF1 may be sent according to one of the following standards:

ISO/IEC 1 8000-2A (frequency band 1 25/1 34.2 kHz, reading distance e.g. up to 2 m)

ISO/IEC 1 8000-2B (frequency band 1 25/1 34.2 kHz)

ISO 1 8000-3 (frequency band 1 3.56 MHz, reading distance e.g. up to 3 m) ISO 18000-7 (frequency band 433 MHz)

ISO 18000-6A (frequency band 860-960MHz, reading distance e.g. up to 3 m)

ISO 18000-6B (frequency band 860-960MHz)

ISO 18000-6C (frequency band 860-960MHz)

EPCglobal Class 0 (frequency band 860-960MHz)

EPCglobal Class 1 (frequency band 860-960MHz)

EPCglobal Class 1 Gen 2 (frequency band 860-960MHz)

ISO 18000-4 (frequency band 2.45 GHz, reading range e.g. up to 12 meters)

(Reference is made to the latest versions of the standards as in force on 1 January 201 0). In particular, the second information INF2 may be sent according to one of the following standards:

Proximity cards: ISO/IEC 14443 (frequency band 13.56 MHz, reading distance e.g. up to 12.5 cm)

Vicinity cards: ISO/IEC 15693 (frequency band 13.56 MHz, reading distance e.g. up to 1 .5 m)

(Reference is made to the latest versions of the standards as in force on 1 January 201 0).

The first information INF1 may also be used in other manner e.g. when counting a plurality of items remotely and substantially simultaneously. This may be useful e.g. when making an inventory in a store or for electronic article surveillance (EAS, anti-theft system). Therefore it may be advantageous to send the first information by far field communication. However, far field communication may have a long reading range, and there may be a risk of contribution from wrong tags. If several tags are simultaneously in the reading range of a reader, a particular item may be erroneously associated with a response sent from a wrong tag.

Before transmitting the second information INF2, the item in question should be identified unambiguously, i.e. it should be ensured that the first information INF1 is read from a tag which is associated with the item in question, and that the corresponding second information INF2 is stored only in a tag which is associated with said item.

The first information INF1 and the second information INF2 may be stored in the same tag associated with an item. Alternatively, the first information INF1 and the second information INF2 may be stored in different tags associated with the same item.

Contribution from wrong tags (associated with other items) may be prevented e.g. by limiting the transmitting power of the reader, by using a directional (transmitting and/or receiving) antenna and/or by using an auxiliary radiation-isolating shield. Thus, a method according to the present invention may comprise preventing transmission of second information INF2 from the other tags to the reader e.g. by limiting transmitting power, by using directional antennas and/or by using radiation-isolating structures. The POS system may comprise means for preventing communication with the wrong tags.

When reading the first information INF1 , a maximum reading distance for reading the first information INF1 may be limited such that the distance between the tag 50, 50a containing the first portion 1 0 and the reader 21 0 is e.g. smaller than 0.5 meters, advantageously smaller than 0.2 meters, or even smaller than 0.05 meters.

Thus, it can be ensured that first information INF1 sent as a response to an interrogation signal originates only from a tag, which is in the vicinity of the reader 21 0. The maximum reading distance may be defined e.g. by setting transmission power of the reader, by setting sensitivity of the reader and/or by setting transmission power of the tag. When reading the first information INF1 , the maximum reading distance may be limited e.g. by keeping the level of the interrogation signal sent by the reader 21 0 below a predetermined level. Consequently, only the tag 50, 50a which is in the vicinity of the reader 21 0 receives a sufficient signal level for initiating sending of a response, which contains the first information INF1 .

The maximum reading distance may also be limited by defining a minimum signal level for the response. The reader 201 may accept a response containing the first information INF1 only when the signal level of the response exceeds a predetermined minimum signal level. Consequently only the tag 50, 50a which is in the vicinity of the reader 21 0 may be capable of providing a sufficiently high signal level. If the distance between the tag and the reader is greater than said maximum reading distance, then a low signal level of a response indicates that the distance between the tag and the reader is greater than the predetermined maximum reading distance.

The reader 21 0 may be capable of scanning plurality of tags substantially simultaneously e.g. for identifying all items in a shopping cart. On the other hand, when the intention is to write the second information INF2 to tag 50, 50b associated with a particular item, the maximum reading distance may be temporarily limited for the purpose of unambiguous identification of the tag (unambiguous identification of the item) positioned in the vicinity of the reader 21 0. In other words, the reader 21 0 may have two operating modes. The first mode may be for unambiguous identification of a single tag (item). The second mode may be for scanning of a plurality of tags. In the second mode, the reading distance may be substantially longer than in the first mode. In the first mode, the maximum reading distance may be e.g. shorter than 0.5 meters. In the second mode, the maximum reading distance may be e.g. longer than 2 meters. A reading sector may also be defined e.g. by using directional antennas. A directional antenna of a reader may be sensitive to a signal originating from a location inside the reading sector (reading area), and it may be insensitive to a signal originating from a location outside the reading sector. The angular width of the reading sector may be e.g. smaller than 70 degrees (when signal level or sensitivity of the antenna at the boundaries of the sector is 3 dB lower than at the center of the sector).

For additional verification, the type of the item in question may be e.g. displayed on the display 390 as written information and/or as graphical information. For example, if the payment is associated with a microwave oven, the text "MICROWAVE OVEN" and/or a graphical image of a microwave oven may be displayed. Thus, the shopkeeper and/or customer may visually check that payment is made for the correct item.

If extremely high reliability is required, the identification of a particular item may also be supplemented e.g. by reading an optical bar code attached to the item and/or by optically reading an identification word or number attached to said item, and entering said word or number into the POS system, in addition to reading the first information INF1 sent by radio communication.

The term "transponder" may refer to an electronic device, which is capable of providing an electric response signal to an electric interrogation signal. The term "transponder" may also refer to radio frequency communication device, which is capable of providing an electromagnetic response signal to an electromagnetic interrogation signal. Referring to Figs. 6-7b, the transponder 1 1 may also be understood to comprise the antenna structure A1 , A2. In other words, the antenna structure A1 , A2 may be a part of the transponder 1 1 . The transponder 21 may also be understood to comprise the antenna structure CA3. The various aspects of the invention are illustrated by the following examples:

Example 1 . A point of sales system (500), comprising:

- a reader (21 0) for reading first information (INF1 ) stored in a radio frequency identification tag (50),

- a payment unit (300) for confirming a payment associated with said first information (INF1 ),

- a control unit (400) configured to enable sending second information (INF2) when a payment associated with said first information (INF1 ) has been confirmed, and

- a transmitter (220) for sending the second information (IN F2) to a radio frequency identification tag (50). Example 2. The system (500) according to example 1 further comprising a radio frequency identification tag (50) attached to an item (1 00), wherein the reader (21 0) is arranged to read the first information (INF1 ) stored in a first portion (1 0) of the radio frequency identification tag (50), and wherein the transmitter (220) is arranged to send the second information (INF2) to a second portion (20) of said radio frequency identification tag (50).

Example 3. The system (500) according to example 1 further comprising a first radio frequency identification tag (50) attached to an item (1 00), and a second radio frequency identification tag (50), wherein the reader (21 0) is arranged to read the first information (INF1 ) is stored in a first portion (1 0) of the first radio frequency identification tag (50), and wherein the transmitter (220) is arranged to send the second information (INF2) to a second portion (20) of the second radio frequency identification tag (50).

Example 4. The system (500) according to any of the examples 1 to 3 comprising means (21 0) for erasing the first information (INF1 ) stored in the first portion (1 0). Example 5. The system (500) according to any of the examples 1 to 4 comprising a tag dispenser (280) configured to provide a radio frequency identification tag (50) for storing said second information (INF2).

Example 6. The system (500) according to any of the examples 1 to 5, wherein said reader (21 0) is arranged to communicate according to a far field communication protocol (ISO 1 8000-6), and said transmitter (220) is arranged to communicate according to a near field communication protocol (ISO 1 5693).

Example 7. A method of using a point of sales system (500), said point of sales system (500) comprising a reader (21 0), a payment unit (300), a control unit (400), and a transmitter (220), said method comprising: - reading first information (INF1 ) stored in a radio frequency identification tag (50) by said reader (21 0),

- confirming a payment associated with said first information (INF1 ) by said payment unit (300),

- enabling sending second information (INF2) by said control unit (400) when the payment has been confirmed, and

- sending the second information (INF2) to a radio frequency identification tag (50) by said transmitter (220).

Example 8. The method of example 7 wherein the first information (INF1 ) has been stored in a first portion (1 0) of a radio frequency identification tag (50) attached to an item (1 00), and wherein the the second information (INF2) is stored in a second portion (20) of said radio frequency identification tag (50). Example 9. The method of example 7 wherein the first information (INF1 ) has been stored in a first portion (1 0) of a radio frequency identification tag (50) attached to an item (1 00), and wherein the the second information (INF2) is stored in a second portion (20) of a different radio frequency identification tag (50). Example 1 0. The method according to any of the examples 7 to 9 wherein a tag (50) for storing said second information (INF2) has been attached to said item (1 00) already before the confirmation of the payment.

Example 1 1 . The method according to any of the examples 7 to 9 wherein a tag (50) for storing said second information (INF2) is attached to said item (1 00) after the confirmation of the payment. Example 1 2. The method according to example 1 1 comprising providing a tag (50) by a tag dispenser (280) after the confirmation of the payment.

Example 1 3. The method according to any of the examples 7 to 1 2 comprising reading said first information (INF1 ) according to a far field communication protocol (ISO 1 8000-6), and transmitting said second information (INF2) according to a near field communication protocol (ISO 1 5693). Example 1 4. The method according to examples 1 3 wherein a maximum reading distance for reading the first information (INF1 ) by the reader (21 0) is limited to be smaller than 0.5 meters, preferably smaller than 0.2 meters. Example 1 5. The method according to any of the examples 7 to 1 4 comprising erasing the first information (INF1 ) stored in a radio frequency identification tag (50).

For the person skilled in the art, it will be clear that modifications and variations of the devices and the methods according to the present invention are perceivable. The drawings are schematic. The particular embodiments described above with reference to the accompanying drawings are illustrative only and not meant to limit the scope of the invention, which is defined by the appended claims.

Claims

1 . A method of using a point of sales system (500), said point of sales system (500) comprising a reader (21 0), a payment unit (300), a control unit (400), and a transmitter (220),

said method comprising:

- identifying an item (1 00) based on the first information (INF1 ),

2. The method of claim 1 wherein the first radio frequency identification tag (50a) has been attached to an item (1 00) before the confirmation of the payment, and the second radio frequency identification tag (50b) is attached to the item (1 00) after the payment has been confirmed.

3. The method according to claim 2 comprising providing the second radio frequency identification tag (50b) by a tag dispenser (280) after the confirmation of the payment.

4. The method according to any of the claims 1 to 3 comprising reading said first information (INF1 ) according to a far field communication protocol (ISO 1 8000-6), and transmitting said second information (INF2) according to a near field communication protocol (ISO 1 5693).

5. The method according to claim 4 wherein a maximum reading distance for reading the first information (INF1 ) by the reader (21 0) is limited to be smaller than 0.5 meters, preferably smaller than 0.2 meters.

6. The method according to any of the claims 1 to 5 comprising erasing the first information (INF1 ) stored in the first radio frequency identification tag (50).

7. A point of sales system (500), comprising:

- a reader (21 0) for reading first information (INF1 ) stored in a first radio frequency identification tag (50a) attached to an item (1 00),

- a transmitter (220) for sending the second information (IN F2) to a second radio frequency identification tag (50b).

8. The system (500) according to claim 7 comprising means (21 0) for erasing the first information (INF1 ) stored in the first radio frequency identification tag (50a).

9. The system (500) according to claim 7 or 8 comprising a tag dispenser (280) configured to provide the second radio frequency identification tag (50b).

1 0. The system (500) according to any of the claims 7 to 9, wherein said reader (21 0) is arranged to communicate according to a far field communication protocol (ISO 1 8000-6), and said transmitter (220) is arranged to communicate according to a near field communication protocol (ISO 1 5693).