Abstract:
The reading of data from a memory tag to another device, using a memory tag reader, is described. The other device has an active portion which can detect the presence and position of the memory tag reader when brought adjacent to it. The memory tag reader is brought adjacent to the memory tag and data uploaded into the memory tag reader. The memory tag reader is moved adjacent to the active portion of the other device into a position which identifies the location to which the data is to be transferred. The data is then downloaded into that location in the other device. A similar process is described for downloading data from the other device to the memory tag. Apparatus appropriate to carry out each stage of these processes is described.

Description:
FIELD OF THE INVENTION 
   The invention relates to a method of transferring data from a memory tag to another device and to apparatus for reading data from memory tags and in some cases also for writing data to such tags. 
   BACKGROUND OF THE INVENTION 
   Memory tags may most generally be considered as memory devices that are not self-powered but which provide input and or output when powered (rather than only when placed in an appropriate drive, such as a CD). Such memory tags may thus be used in situ in any physical environment where they can be powered. 
   Existing memory tags typically comprise a transponder (an electrical device designed to receive a specific signal and automatically transmit a specific reply)—Radio Frequency Identification (RFID) tags are one such form of tag. RFID tags come in many forms but all comprise an integrated circuit including a memory, in which in use information can be stored, and a coil which enables the circuit to be interrogated by a reader which also powers it by means of an inductive (wireless) link. Until recently RFID tags have been quite large, due to the frequency they operate at (13.56 MHz) and the size of coil they thus require, and have had very small storage capacities. Such RFID tags have tended to be used in quite simple applications, such as for file tracking within offices or in place of or in addition to bar codes for product identification and supply chain management. 
   Much smaller RFID tags have also been developed, operating at various frequencies. For example Hitachi-Maxell have developed “coil-on-chip” technology in which the coil required for the inductive link is on the chip rather than attached to it This results in a memory tag in the form of a chip of 2.5 mm square, which operates at 13.56 MHz. This chip is capable of both being read and being written to. In addition Hitachi has developed a memory tag they call a “mu-chip” which is a chip of 0.4 mm square and operates at 2.45 GHz. This chip is written with data during the manufacturing process in Read-Only-Memory (ROM), but is small enough to be embedded in paper. 
   Many uses of memory tags are already known, as indicated above. However, as the storage capacity of the memory tags increases their uses are becoming more to do with data storage rather than simply as a convenient place to store a single number or very limited data. For example Eastman Kodak Company has proposed a range of applications relating to images, presumably intended for use with photographic images, whereby data relating to the images is stored in RFID tags connected to the substrate on which the photographs are printed, e.g. as disclosed in EP 1 076 316 A2 and U.S. Pat. No. 6,363,239 B1. 
   Many forms of readers and reader/writers for communication with memory tags are also known. Some are wireless and hand held but simply display the limited information read from the tag on a small screen, such as those used to read the tags implanted into pet animals. Others, such as those manufactured by TEK Industries, Inc. and apparently intended for use in supply chain management, are wireless and hand held and store the information from a number of memory tags in internal memory before being downloaded to computer using a cradle or alternative connection technique using additional apparatus. Other readers, also available from TEK Industries, Inc. and capable of writing as well as reading, couple to a personal digital assistant (PDA) to form a single hand held unit and communicate (for example the TEK Stationary Reader) immediately with the PDA. Yet other forms of readers and reader/writers are known which are integral with large fixed equipment such as printers, or are simply hardwired to a computer. 
   The invention provides assistance in making practical use of the developments in RFID technology, and indeed in any other memory tag technologies, in relation to the ease with which data stored in the memory tags may be read and transferred elsewhere. 
   SUMMARY OF THE INVENTION 
   In one aspect there is provided a method of transferring data from a memory tag to another device, using a memory tag reader, wherein the other device has an active portion which can detect the presence and position of the memory tag reader when brought adjacent to it, the method comprising the steps of: bringing the memory tag reader adjacent to the memory tag; uploading the data into the memory tag reader; moving the memory tag reader adjacent to the active portion of the other device into a position which identifies the location to which the data is to be transferred, and downloading the data into that location in the other device. 
   According to a second aspect of the invention there is provided a method of transferring data to a memory tag from another device, using a memory tag reader/writer, wherein the other device has an active portion which can detect the presence and position of the memory tag reader/writer when brought adjacent to it, the method comprising the steps of: identifying the data to be transferred, bringing the memory tag reader adjacent to the active portion of the other device; uploading the data into the memory tag reader, moving the memory tag reader adjacent to the memory tag, and downloading the data into the memory tag. 
   According to a third aspect of the invention there is provided a reader to read data from a memory tag and transfer it to another device, having a memory in which to store the data temporarily once read from the memory tag, wherein the reader is responsive to a download instruction from another device to which it is adjacent to download the data read from the memory tag. 
   According to a fourth aspect of the invention there is provided apparatus for transferring data from a memory tag to another device, comprising a memory tag reader having a memory in which to store the data temporarily once read from the memory tag and an active portion of the other device which can detect the presence and position of the memory tag reader when brought adjacent to it. 
   According to a fifth aspect of the invention there is provided apparatus for transferring data to a memory tag from another device, comprising a memory tag reader/writer having a memory in which to store the data temporarily once read from the other device and an active portion of the other device which can detect the presence and position of the memory tag reader/writer when brought adjacent to it. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
       FIG. 1  schematically illustrates a memory tag and a read/write device as known in the prior art; 
       FIG. 2  schematically illustrates a first embodiment of a read or read/write device according to the invention; 
       FIG. 3  schematically illustrates the embodiment of  FIG. 2  in use; 
       FIG. 4  illustrates the method of transfer of data from the memory tag to the computer for the embodiment of  FIGS. 2 and 3 ; 
       FIG. 5  schematically illustrates a second embodiment of a read/write device according to the invention; 
       FIG. 6  schematically illustrates a third embodiment of a read/write device according to the invention, and 
       FIG. 7  schematically illustrates a fourth embodiment of a read/write device according to the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to  FIG. 1  the basic operation of a RFID-type memory tag  10  and of a basic read/write device  12  will be described. The memory tag  10  includes an antenna coil L 1  and a capacitor C 1  connected in parallel therewith to form a resonant circuit. It further includes a memory M 1  and processing and power circuit P 1 . The read/write device  12  includes an antenna coil L 2  and a capacitor C 2  in parallel therewith to form a resonant circuit, and a processing and signal generating circuit P 2 . 
   A signal generator with in P 2  generates a signal at the chosen frequency, such as 2.45 GHz, this is applied to the antenna coil L 2  and thus generates an electro-magnetic field which, provided the memory tag  10  is sufficiently close to the read/write device  12 , penetrates the antenna coil L 1  of the memory tag  10 . By induction a voltage is thus generated in the antenna coil L 1 , this is rectified in circuit P 1  and used to power the memory tag  10 . The capacitance of the capacitors C 1  and C 2  is selected such that the resonant circuits are both resonant at the frequency generated by the signal generator, in order to maximise transmitted signal strength and received signal. 
   When data is to be written to the memory tag  10  by the read/write device  12  the radio frequency signal generated in P 2  is modulated, e.g. amplitude modulated, with the data before being applied to the antenna coil L 2  and transmitted. The signal received by the memory tag  10  by inductive coupling thus both powers the memory tag  10  and communicates with it, the circuit P 1  separating the data signal from the carrier and passing data for storage to the memory M. 
   Similarly, if data is to be read from the memory tag  10  the circuit P 1  applies a signal indicative of the data to the antenna coil L 1  which is detected, as a result of the inductive coupling, by antenna coil L 2  and deciphered in circuit P 2  before being passed from the read/write device  12  to where ever it is required. This signal may for example be transmitted using load modulation. In RFID systems such as this the power consumed by the memory tag  10  can be measured as a drop in voltage across the internal resistance of the antenna coil L 2  of the read/write device  12 . A load resistance within the circuit P 1  may be switched on and off, thus altering the power consumed by the memory tag  10  which is then detected as an amplitude modulation of the voltage across the antenna coil L 2  of the read/write device  12 . 
   Referring now to  FIG. 2 , a read device (or reader)  14  according to the invention will be described. In addition to the functional units described above with reference to  FIG. 1 , those parts being like referenced in  FIG. 2 , the read device  14  includes a memory M 2 , a communication unit U and a battery B as it is a hand held wireless device. Conveniently the read device  14  has a physical shape not dissimilar to a pen. 
   The read device  14  is configured such that when it is switched on, and brought adjacent to a memory tag  10 , the drop in voltage across L 2  is detected and the processor P 2  automatically reads data from the memory M 1  of the memory tag  10  as described above. The data thus read is stored in the memory M 2  of the read device  14 . 
   When it is desired to download the data from the memory M 2  of the read device  14 , the read device  14  is brought adjacent to a touch sensitive screen  16  of a PDA, personal computer (PC) or other computer  18 , as shown in  FIG. 3 , and then the screen  16  is touched at a location to indicate where the data in the memory M 2  should be downloaded to, e.g. into a particular file, or into a particular location in a document The computer  18  is configured to detect the read device  14  touching, or being located adjacent to, the screen  16  and in response to trigger the download of the data from the memory M 2 . The communication between the read device  14  and the computer  18  is via the communication unit U and by any appropriate wireless means, of which a number are known, such as infra red, or Bluetooth. 
   The method of transferring data from the memory tag  10  to the computer  18  is illustrated by the flow diagram of  FIG. 4 . 
   The method may be implemented as follows. The computer  18  will run some form of windows management software, such as Microsoft Windows® which will typically include software to interface with a stylus intended for use with the computer  18  and its screen  16 . Such software is also generally able to support alternative special function human interface devices, such as the read device  14 , but if not special interface software may be provided. When the read device  14  is brought into contact with the screen  16  it will initially act as the stylus intended for use with the computer  18 . That is the location of the read device  14  will be detected and passed to the program controlling the relevant window. This will cause that program to select the object displayed at the relevant location on the screen  16  as the target of an operation, in this case the insertion point for the data being downloaded from the memory M 2  of the read device  14 , and the triggering of that download by causing the computer  18  to send an appropriate instruction to the read device  14 . The download from the read device  14  is conveniently triggered when the read device  14  is moved from contact with the screen  16 , as this will cause a change in the status of the screen  16  which will be detected by the relevant program (the stylus driver). Thus the stylus driver interrogates the read device  14  over the wireless link, via the communication unit U and processor P, as described above and co-ordinates the download of the data into the computer  18 . 
   As described above the read device  14  is just that, as far as the memory tag  10  is concerned, a read device, but it may readily also be configured to write whatever is in its memory M 2  to a memory tag  10 , in which case it will be a read/write device. The data in the memory M 2  may have been read from another memory tag  10 , as described previously, or may have been uploaded from a computer  18 . In the latter case this may conveniently operate as follows. The data to be uploaded is highlighted on the screen  16  of the computer  18 , and may for example be a section of a document or a whole document. The highlighting may be undertaken by a combination of key strokes and/or use of the mouse, or other interface device. Alternatively the read/write device  14  may be used to highlight the relevant document or portion thereof by touching it onto the screen  16  at the start of the portion and dragging it to the end of the portion before lifting off from the screen  16 . 
   If highlighting is undertaken by the former method, the read/write device  14  is then touched onto the screen  16  at the location of the highlighted data and when the read/write device  14  is lifted from the screen  16  this triggers the computer  18  to upload the highlighted data to the memory M 2  of the read/write device  14 . If the highlighting is undertaken by the latter method, the action of lifting the read/write device  14  from the screen  16  at the end of highlighting the portion for upload, triggers the upload to take place. 
   The read device or read/write device  14  provides a very simple and convenient method for the transfer of data from a memory tag  10  into a document on a computer, or to transfer it in the other direction into the memory tag  10 . Thus for example if the memory tag  10  is located on an image print  20 , on which an image  22  might for example be in low resolution as it is purely for library purposes, and contains the full image data in high resolution then the image  22  can readily be placed at a desired location in a document being prepared on the computer  18 . 
   The read/write device  14  described above does have one disadvantage in that when taken adjacent to a memory tag  10  it automatically downloads the contents of its memory M 2  to the memory tag  10  and this might overwrite any data already stored there. There is therefore a need for read/write devices over which the user has more control. 
   Referring now to  FIG. 5 , a second embodiment of a read/write device  30  is very similar to the read/write device  14 , and like parts are like referenced, but it has in addition a download button  32  on the exterior surface thereof for operation by a user. Thus in using the read/write device  30 , as for the device  14 , upload of data from the memory tag  10  is triggered automatically when the read/write device  30  is brought close to the memory tag  10 , but download of data to a memory tag  10  is not triggered automatically. Instead download is enabled by depression of the download button  32 , and then triggered by proximity of the read/write device  30  to the memory tag  10  or alternatively simply triggered by depression of the button  32  when the read/write device  30  is adjacent to the memory tag  10 . The download button  32  may also be depressed to enable download of data to the computer  18 , although the download may be triggered by removing the read/write device  30  from the screen  16  as previously. This again helps to ensure that data already stored in a particular location is not overwritten accidentally. Uploading of data from a computer  18  to the read/write device  30  will be as described above for the device  14 . 
   Referring now to  FIG. 6 , a third embodiment of a read/write device  40  is very similar to the read/write device  30 , and like internal functional blocks are like referenced, but it has both a download button  42  and an upload button  44  on the exterior surface thereof for operation by a user. Thus in using the read/write device  40  download of data to a memory tag  10  is not triggered automatically when the read/write device  40  is brought close to the memory tag  10  but is enabled by depressing the download button  42 . Similarly, when using the read/write device  40  download of data to computer  18  is not triggered automatically when the read/write device  40  is touched onto the screen  16  of the computer  18  but is enabled by depressing the download button  42 . 
   When using the read/write device  40  to upload data, then in a similar fashion, the upload button  44  is depressed to enable (or in some cases trigger) upload of data from a computer  18  for subsequent download to a memory tag  10 , or upload of data from a memory tag  10  for subsequent download to a computer  18 . The highlighting of data to be uploaded from the computer  18  will be as described previously for the device  14 . 
   Referring now to  FIG. 7 , a fourth embodiment of read/write device  50  has similarities to the read/write devices previously described and like internal functional blocks are like referenced. The read/write device  50  has separate read head  52  and write head  54  which are conveniently located at opposite ends of the read/write device  50  and are preferably clearly distinguished visually such as by being different colours or shapes. 
   The read head  52  includes the antenna coil L 2  and capacitor C 2  forming a first resonant circuit as previously described, and a first touch sensitive switch  56 . The write head  54  includes, in similar fashion, an antenna coil L 3  and capacitor C 3  forming a second resonant circuit, and a second touch sensitive switch  58 . 
   A single button  59  is provided which may have a variety of uses depending on the programming within the processor P of the read/write device  50 . For example write operations may suppressed unless the button  59  is depressed to enable them. 
   The read/write device  50  may be used as follows. When the read head  52  is brought adjacent to a memory tag  10  the first resonant circuit L 2 , C 2  couples in the normal manner with the memory tag  10  and data is read into the memory P 2  of the read/write device  50 . When the read head  52  is brought into contact with the screen  16  of the computer  18  the pressure sensitive switch  56  is activated which signals to the processor P 2  that a read operation from the computer  18  is required, and this is then initiated by removing the read/write device  50  from contact with the screen  16 . The data to be uploaded form the computer  18  may have been highlighted as previously described, by key strokes or mouse use, or by means of the read/write device  50  being dragged across the screen  16 . 
   When the write head  54  is brought adjacent to a memory tag  10  the first resonant circuit L 2 , C 2  couples in the normal manner with the memory tag  10  and data is written into the memory M 1  of the memory tag  10  from the memory P 2  of the read/write device  50 . When the write head  54  is brought into contact with the screen  16  of the computer  18  the pressure sensitive switch  58  is activated which signals to the processor P 2  that a write operation to the computer  18  is required, and this is then initiated by removing the read/write device  50  from contact with the screen  16 . 
   The use of the pressure sensitive switches  56 ,  58  may also be used in the control of communication between the read/write device  50  and the memory tag  10 . In addition the contents of the memory M 1  of a memory tag  10  may be deleted by applying the write head  54  of the read/write device  50  to the memory tag  10  when the memory M 2  of the read/write device  50  is empty. 
   The embodiments of read and read/write devices according to the invention described above have been described as downloading the data read from a memory tag to a computer. However, they may alternatively be used to download the data directly to a printer for immediate printing, or to download the data into another memory tag. 
   Embodiments of read and read/write devices according to the invention may also be constructed which omit the battery and have a connection to an external power source. Furthermore embodiments may be constructed which are not wireless but which are connected to a computer, printer or other device to which the data from memory tags is to be downloaded by a wired connection. However, they would retain the functionality described above whereby the location to which the data is to be downloaded is identified by contact with the screen of the computer or similar contact with the other device. The screen of the computer may not be touch sensitive but may use any of the other known ways of detecting the presence of a read or read/write device. 
   Embodiments of read and read/write devices according to the invention may also include visual indicators on their external surfaces, such as LEDs which light up or a small LCD screen on which information can be displayed, to communicate the status of the device to a user. The devices may also or alternatively provide audible signals to assist the user, for example they might beep to indicate that a download or upload has been completed.