Background of the Invention The invention relates to a product recognition system. The invention is in particular applicable to a product recognition system for use in a retail store, but can have many other uses.

In addition to the trade name and product description to be found on a product label, it is common for manufacturers of retail products to incorporate a machine-readable product code into the label on each product. The product codes are commonly in the form of an optical barcode, which can be read by a barcode reader, but which is unintelligible to the shopper. Several standards for such barcodes exist, including the Universal Product Code (UPC), and the European Article Number (EAN), which have become European standards.

Some people have difficulties in shopping in a self-service retail store, due to not being able to read the product description or the trade name on the product label. Such people include the visually impaired generally, that is partially sighted or completely blind people, as well as those unable to read, or who have difficulty reading. We have appreciated that the barcode itself can however be used in such a way as to enable such persons to'read'the label without difficulty.

Summary of the Invention The present invention in its various aspects is defined in the independent claims below to which reference should now be made. Advantageous features of the invention are set forth in the appendant claims.

A preferred embodiment of the invention is described below with reference to the drawing, and comprises a product recognition system for use in a supermarket or like retail store. The system includes a plurality of customer product recognition units and a central unit.

Customers who are visually impaired can scan barcodes on the products with a scanner. The output of the scanner is transmitted by a UHF radio link together with a code identifying the particular unit to the central unit comprising a PC. The product code is looked up in a database and a corresponding description is applied to a voice synthesizer. A sound signal is transmitted by a VHF radio link to the customer unit and is played to the customer over earphones.

Brief Description of the Drawing A preferred embodiment of the invention will now be described with reference to the drawing in which the sole figure shows the components which make up a preferred system embodying one aspect of the invention.

Detailed Description of the Preferred Embodiment The product recognition system 10 illustrated in the drawing is designed for use in a retail store and includes customer product recognition units 20 carried by the shoppers, and a central in-store computer 50. In practice there will of course be a substantial number of product recognition units 20, which may be used simultaneously by different shoppers, but there need be only one central

unit 50. The product recognition units 20 are preferably portable so that a customer may easily carry one around the store. Alternatively, they may be attachable to movable trolleys, such as supermarket shopping trolleys.

The product recognition unit 20 is shown in the lower part of the Figure. It comprises a transmission part 22 and a reception part 24, which could be combined or share components in common. The transmission part 22 consists of a barcode scanner 26 for scanning optical barcodes on products, a customer unit identification code unit 27, a UHF (ultra high frequency) transmitter 28, and a transmission antenna system 30. The reception part 24 consists of a receiving antenna system 32, a VHF (very high frequency) receiver 34, a customer unit identification decoding unit 35, and an audio output device 36. The audio output device conveniently takes the form of an earphone or pair of earphones, but could be constituted by a small loudspeaker or other electrical to audio transducer, such as a hearing aid. The unit also includes a power supply (not shown so as to avoid undue complexity) the connections of which will be understood by those skilled in the art. The power supply includes a battery in the form of a dry cell.

The unit 20 can communicate through the antenna systems 30 and 32, receiver 34, and transmitter 28, with the in-store computer 50, using a UHF link, diagrammatically shown at 40, for upward transmission from the product recognition unit 20 to the central unit 50, and using a VHF link, diagrammatically shown at 42, for downward transmission from the central unit 50 to the product recognition unit 20.

The central unit 50 is based around a personal computer (PC) 52 which may be of the well-known IBM standard. Most of the internal components of the PC 52 are not shown in the Figure to avoid undue complexity, but they will be understood by those skilled in the art. The PC includes a central processing unit, and is provided with storage 54 in the form variously of read-only memory (ROM), random-access memory (RAM) and a hard disk. For present purposes it is sufficient to note that the storage contains working software 56 and a database or look-up table 58. The PC also has a display screen 70 and a keyboard 72. Associated with the PC is a sound card and voice synthesizer 60.

The central unit 50 communicates with the product recognition units by means of a receiving antenna system 62 and an UHF receiver 64, which receive signals from the UHF transmitter 28 and transmission antenna system 30 in the product recognition units 20, and a VHF transmitter 66 and transmitting antenna system 68 which transmit signals to the receiving antenna system 32 and VHF receiver 34 in the product recognition units 20.

Each product in the store carries an optical barcode representative of a unique product code or number.

Generally this barcode will have been put on the product by the original manufacturer, but for some products the barcode may be generated in the store itself. The database 58 at the central unit 50 contains for each product code a corresponding associated character string.

Each character string comprises information about the product having that product number.

The use of the illustrated system will now be described. On entry to the store, a customer with

impaired sight first picks up a product recognition unit 20, and puts on the earphone or earphones constituting the audio output device. When the customer wants to know what a product in front of them is, he or she simply picks up the product and scans the barcode on the product label using the optical barcode scanner 26. The output of the barcode scanner is combined with a customer unit identification code in unit 27 and is then applied to the UHF transmitter 28 in the customer product recognition unit 20. The transmitter 28 sends a UHF signal via the transmission antenna system 30 over the link 32 to the receiving antenna system 62 and the UHF receiver 64 in the central unit 50. This signal thus identifies the barcode that has just been scanned, and includes an identification code which is unique to that particular scanner 26 or that unit 20.

This signal is received by the receiver 64 and passed to the PC 52. The PC 52 looks up the barcode number received from the unit 20 in the database 58 stored in the storage 54, and finds the character string which corresponds to that barcode. This character string is then sent by the PC 52 to the sound card and voice synthesizer 60, together with an identification signal indicating which customer product recognition unit the request emanated from. In this example the same customer unit identification coding scheme is used for the upward and downward transmission. The sound card and voice synthesizer, using known software, converts the character string into a series of phonemes. This series of phonemes forms an electrical sound signal which constitutes a verbal message identifying the product scanned. From the sound card 60, this electrical sound signal is sent to the

VHF transmitter 66, along with the customer unit identification code. The transmitter 66 then transmits a signal comprising the sound data and the identification code via the transmission antenna system 68 and the VHF link 42.

This signal is received by all the units 20, but will be discarded by the decoding unit 35 in all the units except the unit which has the corresponding identification code. This unit 20 then plays over the earphones 24 an audible message identifying the product which has just been scanned. In this way, simply by scanning the product, the shopper hears through the earphones a voice telling them what the product is.

The information heard by the shopper can, with very slight additional complexity, also include the price, as this will be held in the in-store computer. Information about special offers, or about other products related to the particular product being scanned may also be included.

A practical embodiment of the system can be designed on the following basis. The upward link 40 is a UHF link, and this may be based on known optical radio barcode readers of the type which are used to handle large items at a store checkout. These operate akin to a cordless telephone, and include components corresponding to the barcode scanner 26, UHF transmitter 28, and antenna system 30. Receiver units for use with them include components corresponding to the antenna system 62 and the UHF receiver 64. The downward link 42 is a VHF link, and this may for example be based on technology developed for use in baby alarms and the like. The system can operate in full duplex, handling upwards and downwards transmissions simultaneously.

Alternatively the system may use the same transmission and reception band between the customer unit 20 and the central unit 50. In principle, any wire-less link between the central unit and the customer units may be used. Other frequencies to those described may be employed for transmission, including for example infra-red frequencies.

The system could be combined with an in-store Local Area Network (LAN) arranged so that the location of the unit 20 can be tracked around the store. On receiving information on the position of the customer in the store, a message identifying the types of product in the locality of the customer could be sent to the customer in the same manner as described above.

The equipment illustrated thus provides a product recognition system in which, when a product is scanned using a product recognition unit, a message identifying the product which has been scanned is sent to a set of earphones assigned to that unit. This enables individuals with sight or reading problems, who would otherwise have trouble identifying the product they had picked up, quickly to identify the product.

The system illustrated is particularly convenient, in that new product codes can quickly and simply be added to the system, merely by changing the table stored in the database associated with the in-store PC. It is not necessary to make any changes at the individual units.

Changes in price, in particular, can very readily be made.

The system can be arranged to operate in a"learning" mode. In the learning mode, products are scanned, and if a product code is scanned which does not exist in the database, or which exists but which has no associated

character string, then a message is displayed on the screen 70 of the PC 52 inviting the operator to enter a description etc. for that product. This description is entered via the PC keyboard 72.

The system has been described for use in a retail store, but other applications can be envisaged. For example, it can be used in a dispensary or hospital to provide information about medicines.

In a hospital the medicine containers can be barcoded and each patient also given a barcode securely attached to their person. When dispensing medicines from a dispensing trolley, the nurse reads the patients bar code which is transmitted to a central unit by radio link together with an identification code indicating the particular dispensing trolley. The central unit returns a code or codes indicating the appropriate medicines for that patient, which are announced to the nurse. In an extension of the system, the nurse then scans the medicine containers to confirm that the correct drugs are being prescribed.

The system can be adapted for use in a photographic dark room to provide audible information about items in the dark room. Similarly it can be used in an audio tape, CD, or large print library. The central unit can return the title and also a precis of the plot.

It will be seen that the system has wide application in recognising items and the term"product"as used herein should be construed correspondingly broadly.