JP5935536B2 - IC card with display and communication system using the same - Google Patents

Description

  The present invention relates to a non-contact display-equipped IC card having display means using an electrophoretic display element and a communication system using the same.

  In recent years, a display element having a memory property has attracted attention from the viewpoint of extremely low power consumption. As a display element having a memory property, an electrophoretic display element that performs display by movement of charged particles, a liquid crystal element, and the like are well known. In particular, a display panel also referred to as electronic paper using an electrophoretic display element is mounted on a portable electronic device such as an electronic book because of its high contrast and good display quality.

  In such an electrophoretic display element rewriting technique, the display data storage unit stores the data being displayed and the display data to be newly rewritten, and the display transition detection unit detects the transition of the display data to display the data. A configuration is employed in which a display inversion pulse for inverting the display is output only for a segment that needs to be rewritten in the panel (see, for example, Patent Document 1).

  Here, the display panel using the electrophoretic display element according to Patent Document 1 is the same as the display panel used in the present invention, and although this display panel is known per se, it helps to understand the present invention. The configuration and operation principle of the display panel using the electrophoretic display element will be described below with reference to FIGS.

[Configuration and operating principle of display panel using electrophoretic display element]
In FIG. 9, a display panel 50 is an electrophoretic display panel in which charged particles move by electrophoresis. In the display panel 50, a transparent common electrode (common electrode) COM made of an ITO (indium tin oxide) film is formed on the entire back surface of a transparent resin substrate 51, and a microcapsule display layer also called electronic ink is formed thereon. 53 is formed. A flexible printed circuit board (hereinafter abbreviated as FPC) 55 having a segment electrode SEG for each pixel formed on the surface of the microcapsule display layer 53 is adhered and configured by an adhesive layer 54.

  In the microcapsule display layer 53, a large number of microcapsules 60 having a diameter of about several tens of μm are dispersed in a mixture such as a binder, a surfactant, a thickener, and pure water. That is, in the display panel 50, a transparent resin substrate 51 and an FPC 55 are disposed as a pair of substrates, a common electrode COM is formed on one of the opposing surfaces, a segment electrode SEG is formed on the other surface, and a microelectrode is interposed therebetween. A capsule 60 is enclosed.

  Next, the operation principle of the display panel 50 will be described with reference to FIG. In FIG. 10, a microcapsule 60 has white particles 63a made of titanium oxide or the like as charged particles and black particles 63b made of carbon black or the like as charged particles in a capsule shell 61 made of transparent methacrylic resin or the like. It is encapsulated in a state of being dispersed in a transparent dispersion medium 62 having a high density. The white particles 63a are negatively charged, and the black particles 63b are positively charged.

Of the electrodes arranged so as to sandwich the microcapsule display layer 53, one common electrode COM integrated on the entire surface is grounded, and a negative voltage is applied to the segment electrode SEG on the other FPC 55. The negatively charged white particles 63a in the microcapsule 60 are moved to the transparent common electrode COM side, and the positively charged black particles 63b are moved to the segment electrode SEG side. Therefore, when viewed from the viewing side (direction of arrow A), Looks white. On the other hand, in the portion where a positive voltage is applied to the segment electrode SEG, the black particles 63b positively charged in the microcapsule 60 by the electric field in the opposite direction are transferred to the transparent common electrode COM side, and the white particles 63a negatively charged are segmented. Since it moves to the electrode SEG side, it looks black when viewed from the viewing side.

  Therefore, the display state can be changed to white or black depending on the polarity of the voltage applied between the common electrode COM and the segment electrode SEG. At this time, the white particles 63a and the black particles 63b move in the dispersion medium 62 by electrophoresis. However, since the dispersion medium 62 has a high viscosity, the display state is changed by applying a voltage, and then the application of the voltage is stopped. Even so, the intermolecular force of each particle can provide a memory effect that maintains its display state. As a result, the display panel 50 only has to apply a drive voltage only when the display is changed, and thus the power consumption is extremely small.

  Next, FIG. 11 shows an example in which characters such as numbers are displayed on the display panel 50 described above. In FIG. 11, the display panel 50 is composed of a display body that represents a seven-segment character SC consisting of segments S0 to S6 by one digit.

  The display panel 50 has one common electrode COM and seven segment electrodes as electrodes. The seven segment electrodes are segment electrodes SEG0 to SEG6 corresponding to the segments S0 to S6. Further, the eight lines extending from the lower portion of the display panel 50 are lead wires connected to the common electrode COM and the seven segment electrodes SEG0 to SEG6, and each lead wire is connected to each segment to be connected. The same name as the electrode is shown. Each lead wire is connected to a driver circuit (not shown here) that drives the display panel 50.

  Next, FIG. 12 shows a case where the seven segment character SC by the display panel 50 shown in FIG. 11 is changed from a state where the number “2” of (A) is displayed to a state where the number “3” of (B) is displayed. Show. In FIG. 12, in the first display state (A), the segments S0, S1, S3, S4 and S6 are black, and the segments S2 and S5 and the surrounding area S7 are white. In the changed display state (B), the segments S0, S1, S2, S3 and S6 are black, and the segments S4 and S5 are white.

  As a driving method for actual display, in order to change the display state of the seven segment character SC, first, the common electrode COM is always grounded (that is, 0 V) in order to display the number “2” in (A). A positive drive voltage is temporarily applied to the segment electrodes SEG0, SEG1, SEG3, SEG4, and SEG6. Further, a negative voltage is temporarily applied to the segment electrodes SEG2 and SEG5, and thereafter, all the segment electrodes are set to 0 V having the same potential as the common electrode COM.

  Next, in order to change the display to the number “3” in (B), the common electrode COM is always grounded (that is, 0 V), and a positive drive voltage is temporarily applied to the segment electrode SEG2 that changes from white to black. A negative voltage is temporarily applied to the segment electrode SEG4 that changes from black to white. After that, the segment electrodes SEG2 and SEG4 return to 0V, which is the same potential as the common electrode COM, and the segment electrodes SEG0, SEG1, SEG3, SEG5, and SEG6 that do not change continue to be applied with 0V.

In this way, a positive or negative voltage is temporarily applied to the segment electrode for rewriting the display to black or white, and 0 V, which is the same potential as the common electrode COM, is continuously applied to the other segment electrodes whose display does not change. This is because, as described above, the display panel 50 has a memory property, so that the previous display state can be maintained as it is. The above is the configuration and operation principle of the display panel using the electrophoretic display element. Thus, the display panel using the electrophoretic display element has a memory property, so that the display state is maintained even when the power is turned off. I can do it.

  As another technique for rewriting the electrophoretic display element, display data being displayed is stored in the EEPROM before the power supply to the display device is cut off (power off), and the display data is read from the EEPROM when the power is turned on again. An image display device that can acquire and specify display data when the power is turned off is known (for example, see Patent Document 2). According to this image display device, it is shown that the display panel can be completely rewritten or partially rewritten appropriately with reference to display data at the end of display during re-power-on (that is, stored data in the EEPROM). ing.

JP 2009-48077 A (page 9, FIG. 1) JP 2010-169886 (page 13, FIG. 11)

  However, since the power supply is continuously turned on in the display device of Patent Document 1, data that is being displayed in the display data storage unit, which is a volatile memory, and new data to be rewritten will be stored one after another. The display transition detector can detect the transition of the display data and generate a display inversion pulse to the display panel. However, when the display device is incorporated in a power-less device such as an IC card, the power supply is not When stopped, the data being displayed in the display data storage section disappears, and there is a problem that the transition of the data being displayed cannot be detected.

  For this reason, when the power supply is started again (when the power is turned on), the displayed data that has been displayed since the power is turned off is not stored, so the transition of the display data cannot be detected, and the current display It is necessary to erase all the displayed states. That is, it is necessary to perform a reset operation for making all segments black or white, erase the display state, and then rewrite the display. However, if the display reset operation is performed every time the power is turned on, the display is instantaneous but all black or all white, and flickering occurs.

  In addition, in the image display device of Patent Document 2, a nonvolatile memory such as an EEPROM is provided to store display data, but a circuit for comparing display data in the nonvolatile memory with new rewritten display data. There is a problem that display control becomes complicated.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and in an IC card provided with a display means having a memory property, the display rewriting operation is performed reliably, the display card is excellent in display quality, easy to use, and convenient. It is providing the communication system using.

  In order to solve the above-mentioned problems, the IC card with display and the communication system using the same according to the present invention employ the following configurations.

The IC card with a display of the present invention includes a display means having a memory property, and when rewriting the display of the display means, the display data in the power-off state and the rewritten display data to be newly rewritten are displayed. Temporary storage means for temporarily storing; first temporary storage means for extracting and temporarily storing only displayed data from the temporary storage means; and second temporary for extracting and temporarily storing displayed data from the first temporary storage means Storage means, and when the currently displayed data is temporarily stored in the first temporary storage means, a dummy drive command is output under the condition that the display content of the display means is not rewritten, and the first temporary Control means for taking out the data being displayed from the storage means, moving it to the second temporary storage means, and inputting the rewritten display data input to the temporary storage means to the first temporary storage means Furthermore, by comparing the rewriting display data and display the data, characterized by comprising a driving circuit for selecting a desired driving waveform to rewrite a new display of the display means.

  Further, the display data and the rewritten display data are collectively input from the outside of the drive circuit to the temporary storage unit. Alternatively, a non-contact communication circuit for non-contact communication is further provided, and the displayed data and the rewritten display data are collectively input to the temporary storage unit by the non-contact communication circuit. Or it has further a non-volatile memory which memorizes data under display, and data under display is memorized by a non-volatile memory, and data under display moves to a temporary storage means from a non-volatile memory.

  Further, the power supply is switched from a power-off state to a power-on state by non-contact power supply.

  The communication system according to the present invention includes the IC card with display, and a reader / writer that inputs power for rewriting display data and supplies power to the power-on state without contact with the IC card with display. And

  As described above, according to the present invention, when the display unit having the memory property is changed from the power-off state to the power-on state, when the display is newly rewritten, the displayed data at the time of power-off and the new rewritten display data are temporarily stored. By saving and transferring each data in turn to the two temporary storage means, the drive waveform required for rewriting can be easily selected and only the necessary electrodes can be rewritten, as with continuous display rewriting when the power is turned on. Thus, an IC card with a display can be provided that does not complicate the drive circuit and eliminates the need for a display resetting operation and has excellent display quality without flickering or afterimages. In addition, since the IC card with display performs power supply and communication of display data by a reader / writer without contact, the display can be easily rewritten, and the communication system of the IC card with display is easy to use and excellent in convenience. Can be realized.

It is a block diagram which shows the electrical structural example of the IC card with a display of the 1st Embodiment of this invention. FIG. 3 is a block diagram illustrating details of a drive waveform selection circuit and a driver circuit according to the first embodiment of the present invention. It is a top view explaining the mechanical structure of the IC card with a display of the 1st Embodiment of this invention. It is a flowchart explaining the flow of the whole operation | movement of the 1st Embodiment of this invention. It is a timing chart explaining the operation timing of each circuit of the 1st embodiment of the present invention. It is explanatory drawing which shows the example of a transition of the display data which each circuit of the 1st Embodiment of this invention memorize | stores, and the operation | movement of a drive waveform selection circuit. It is a flowchart explaining the flow of the whole operation | movement of the 2nd Embodiment of this invention. It is a block diagram which shows the structural example of the communication system of the 3rd Embodiment of this invention. It is sectional drawing explaining the structure of the display panel by an electrophoretic display element. It is an expanded sectional view explaining the principle of operation of the display panel by an electrophoretic display element. It is a top view which shows an example which displays the numerical character of the display panel by an electrophoretic display element. It is explanatory drawing in the case of changing from the state which displayed the number "2" on the display panel by an electrophoretic display element to the state which displays the number "3".

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[Features of each embodiment]
The feature of the first embodiment is a basic configuration example of the present invention, and the display data displayed when the power is turned off at the time of display rewriting when the display means having the memory property is turned on. Once the new rewritten display data is stored, these two data are transferred to the two temporary storage units in sequence, and only the display segments that need to be rewritten are driven in the same way as the continuous display rewriting drive at normal power-on. It is an example of a structure of the IC card with a display of the one-way communication which has the structure to rewrite. The feature of the second embodiment is a configuration example of an IC card with a display capable of bidirectional communication that transmits an ID number of the IC card before receiving display data. A feature of the third embodiment is a communication system using the IC card with display of the present invention, in which display data is communicated and power is supplied in a non-contact manner with the IC card with display.

[Description of Electrical Configuration of First Embodiment: FIG. 1]
An example of the electrical configuration of the IC card with display according to the first embodiment of the present invention will be described with reference to FIG. In FIG. 1, reference numeral 1 denotes an IC card with a display according to the first embodiment of the present invention. Reference numeral 2 denotes an IC card with a display according to a second embodiment to be described later.
Here, the IC card with display 1 includes an RFID IC 10 (hereinafter abbreviated as RFID 10), a microcomputer 20 (hereinafter abbreviated as microcomputer 20) as a control means, an EIN driver 30, a power supply circuit 40, and a memory. The display panel 50 includes an electrophoretic display element as a display means having a property.

  The RFID 10 is a non-contact communication circuit for non-contact short-distance wireless communication by an electromagnetic induction method called Radio Frequency IDentification (RFID). The RFID 10 includes a non-contact IO 11 that inputs / outputs data without contact with the outside by electromagnetic induction, and an IO register 12 that inputs / outputs data received via a signal line.

  Further, the non-contact IO 11 of the RFID 10 is connected to a communication antenna 14 provided outside the RFID 10. The RFID 10 is not limited to the electromagnetic induction method, and may be a radio wave method. The power generation circuit 40a is connected to the power supply antenna 15 provided outside the power generation circuit 40a, and generates power without contact by electromagnetic induction. The power supply voltage generation circuit 13 of the power supply circuit 40 generates a DC voltage and supplies power to the RFID 10, the microcomputer 20, and the EINK driver 30, but illustration of power supply lines to each circuit is omitted. The power supply voltage generation circuit 40a may be provided inside the RFID 10.

  The microcomputer 20 has a function as a controller for controlling the entire IC card 1 with display, and has an IO register 21 for inputting / outputting data to / from the outside, and a RAM 22 as temporary storage means for storing display data. doing.

  The EINK driver 30 is a driver IC for an electrophoretic display element that drives the display panel 50, and is a general-purpose driver IC that rewrites display contents one after another in a general state, that is, when the power is always on. Good. The EIN driver 30 includes an IO register 31 for inputting / outputting display data to / from the outside, a latch 1 circuit 32 and a latch 2 circuit 33 as temporary storage means, and latch 1 data L1 and a latch 2 circuit as outputs of the latch 1 circuit 32. From the drive waveform selection circuit 34 as drive waveform selection means for inputting the latch 2 data L2 which is the output of 33, the driver circuit 35 for outputting a plurality of segment drive voltages VSEG for driving the display panel 50, and the microcomputer 20 A command register 36 (hereinafter abbreviated as command R36).

  The latch 1 circuit 32 as the first temporary storage means stores the data of the IO register 31 by the latch clock CL1 and outputs it as the latch 1 data L1. The latch 2 circuit 33 stores the latch 1 data L1 by the latch clock CL2 and outputs it as the latch 2 data L2. Both the latch 1 circuit 32 and the latch 2 circuit 33 store display data, and when the display panel 50 described later performs 8-digit display, each digit is represented by 1 byte as an example, and each has an 8-byte configuration. . Details of the drive waveform selection circuit 34 and the driver circuit 35 will be described later.

  As the display panel 50, an electrophoretic display panel in which the charged particles described above with reference to FIGS. 9 to 12 move by electrophoresis is used as an example. The same components as those in the previous configuration are denoted by the same reference numerals, and the display form is an 8-digit display configuration in which eight seven segment characters SC shown in FIG. 11 are arranged as an example. The plurality of segment electrodes of the display panel 50 are connected to the segment drive voltage VSEG from the EINK driver 30, and the common electrode COM of the display panel 50 is connected to 0V.

  The RFID 10, the microcomputer 20, and the EIN driver 30 of the display-equipped IC card 1 are connected by a general serial communication system bus B1 to input / output data. That is, the IO register 12 built in the RFID 10 is connected to the bus B1, the IO register 21 built in the microcomputer 20 is connected to the bus B1, and the IO register 31 built in the EIN driver 30 and the command R36 are connected to the bus B1. Data input / output is performed between the ICs. Note that the bus B1 is not limited to serial, but may be connected in parallel, and the bus B1 may be connected with individual signal lines between the ICs instead of the bus system.

[Configuration explanation of drive waveform selection circuit and driver circuit: FIG. 2]
Next, a configuration example of the drive waveform selection circuit 34 and the driver circuit 35 built in the EINK driver 30 will be described with reference to FIG. Here, the drive waveform selection circuit 34 and the driver circuit 35 are configured to drive each segment of the 8-digit display panel 50 as described above, but in FIG. The description will be made on the assumption that the seven segment display is driven.

In FIG. 2, the drive waveform selection circuit 34 has a comparison circuit 34a and a decoder circuit 34b. The comparison circuit 34a receives the latch 1 data L1 and the latch 2 data L2. Although details of the display data will be described later, the latch 1 data L1 is new rewritten display data, and the latch 2 data L2 is currently displayed data. Since the latch 1 data L1 and the latch 2 data L2 are assumed to be displayed in one digit on the display panel 50 in FIG.

  The comparison circuit 34a compares the new rewritten display data (latch 1 data L1) with the currently displayed data (latch 2 data L2), outputs the transition of the display data as transition data P1, and inputs it to the decoder circuit 34b. To do. The decoder circuit 34b receives the transition data P1 and outputs the rewrite codes C0 to C6 configured by 2 bits to indicate what drive voltage is applied to the segment electrodes S0 to S6 of the seven segments of the display panel 50. .

  The driver circuit 35 receives the rewrite codes C0 to C6 and outputs segment drive voltages VSEG0 to VSEG6 for driving the segment electrodes SEG of the display panel 50. Further, a positive voltage + V and a negative voltage −V, which are power sources for the segment drive voltages VSEG0 to VSEG6, are input from a built-in power supply circuit (not shown). Here, the positive voltage + V is + 15V as an example, and the negative voltage −V is −15V as an example. As described above, if the actual display panel 50 has an 8-digit display, the drive waveform selection circuit 34 and the driver circuit 35 have a circuit configuration in which 8-digit circuits are arranged in series.

[Description of Mechanical Structure of First Embodiment: FIG. 3]
Next, an outline of the mechanical structure of the IC card with display according to the first embodiment will be described with reference to FIG. In FIG. 3, the display-equipped IC card 1 has a thin card-shaped mounting board 3, and two loop antennas are provided on the surface of the mounting board 3. One is a power supply antenna 15 provided along the outer periphery of the mounting substrate 3, and the other is a communication antenna for data communication formed inside the power supply antenna 15 and having a substantially square shape on the left side in the drawing. 14. These two antennas are formed on the base film of the mounting substrate 3 in a loop shape with a metal material such as copper foil, but detailed patterns are not shown.

  In addition, the RFID 10, the microcomputer 20, the EINK driver 30, and the power supply circuit 40 described above are mounted inside the power supply antenna 15 on the surface of the mounting substrate 3. Further, the display panel 50 is disposed on the mounting substrate 3 at the upper right side in the figure inside the power supply antenna 15. As described above, the display panel 50 is composed of an 8-digit seven segment. The display form of the display panel 50 is not limited, the number of digits to be displayed is arbitrary, and although not shown, English characters can be displayed by increasing the number of segment electrodes for each digit. The display form may be used.

  Each component on the mounting substrate 3 is electrically connected by a wiring pattern such as a copper foil, but the wiring pattern is not shown. Although not shown, the display-equipped IC card 1 is completed by covering the front and back surfaces of the mounting substrate 3 with protective members.

  Here, the display-equipped IC card 1 of the present invention is a power-less (battery-less) system. That is, power is supplied in a non-contact manner, an AC voltage is generated by electromagnetic induction from the outside by the power supply antenna 15, and the AC voltage is rectified by the power supply voltage generation circuit 13 (see FIG. 1) and displayed. The power source of the IC card 1 is used. For this reason, since the IC card with display 1 does not require a battery, it can adopt a thin sheet-like form like a normal IC card, and since it does not require battery replacement, the cost is low and the long-term It has the merit that it can be used.

[Description of Operation of First Embodiment: FIGS. 4 and 5]
Next, an outline of the operation of the IC card with display according to the first embodiment will be described with reference to the flowchart of FIG. 4 and the timing chart of FIG. Here, FIG. 4 explains the entire operation flow of the IC card 1 with display, and FIG. 5 explains the operation timing of each circuit. The overall configuration of the IC card with display 1 is shown in FIG. 1, and the configuration of the drive waveform selection circuit 34 and the driver circuit 35 of the EINK driver 30 is shown in FIG. Further, the description will be made on the assumption that an external device (not shown) for transmitting a power carrier and display data is arranged outside the IC card with display 1.

  In FIG. 4, the external device transmits a carrier for power at a predetermined frequency to the IC card 1 with display (FIG. 4: step ST1).

  Next, the IC card with display 1 receives a carrier from an external device by electromagnetic induction by the power supply antenna 15, rectifies the AC signal received by the power supply voltage generation circuit 13 of the RFID 10 and converts it into a DC voltage, FRID 10, The microcomputer 20 and the EINK driver 30 are supplied as power supply voltages, and the IC card 1 with display is turned on (FIG. 4: step ST10, FIG. 5: timing T1).

  Next, the external device modulates the carrier by a predetermined method and transmits the currently displayed data and new rewritten display data in a batch since the IC card with display 1 is in the power-off state (FIG. 4). : Step ST2). Here, if the display data is configured as 8-byte data in which one digit is 1 byte as described above, the currently displayed data is 8 bytes, the new rewritten display data is 8 bytes, and the display data is 16 bytes in total. Is sent.

  Next, the IC card with display 1 receives display data of 16 bytes from the external device by electromagnetic induction by the communication antenna 14 and stores it in the IO register 12 of the RFID 10 (FIG. 4: step ST11, FIG. 5: timing). T2). That is, the RFID 10 inputs the currently displayed data and new rewritten display data at a time T2 in a single reception operation.

  Next, the microcomputer 20 inputs the 16-byte display data of the IO register 12 of the RFID 10 to the IO register 21 via the bus B1 and stores it in the RAM 22 as temporary storage means (FIG. 5: timing T3).

  Next, the microcomputer 20 latches the currently displayed data of 8 bytes of the display data stored in the RAM 22 via the IO register 31 of the EIN driver 30 connected to the bus B1 as a first temporary storage means latch 1. Input to the circuit 32 (FIG. 4: step ST12, FIG. 5: timing T4). Specifically, after the currently displayed data is transferred to the IO register 31, the latch clock CL1 is generated, and the data in the IO register 31 is copied to the latch 1 circuit 32. As a result, the currently displayed data is stored in the latch 1 circuit 32 of the EINK driver 30.

  Next, the microcomputer 20 outputs a dummy drive instruction to the command R36 of the EINK driver 30, and the EINK driver 30 executes dummy drive (FIG. 4: step ST13, FIG. 5: timing T5). This dummy drive command is a display rewrite command in which the drive voltage of the drive waveform, which is a condition that the display contents are not rewritten on the display panel 50, is set to 0 V and the minimum pulse width.

Even if this dummy drive command is executed, the drive voltage of the drive waveform is 0 V and the pulse width is the smallest, so the drive voltage is not output to the display panel 50, so the display content is not rewritten. After execution of the dummy drive instruction, a latch clock CL2 is generated, and the currently displayed data stored in the latch 1 circuit 32 (that is, latch 1 data L1) is the second temporary storage means. The latch 2 circuit 33 stores the currently displayed data (FIG. 5: timing T6). That is, the purpose of executing the dummy drive command is to output the latch clock CL2 and move the currently displayed data to the latch 2 circuit 33.

  Next, the microcomputer 20 inputs new 8-byte rewritten display data of the display data stored in the RAM 22 to the latch 1 circuit 32 via the IO register 31 of the EIN driver 30 connected to the bus B1 (FIG. 4). : Step ST14, FIG. 5: Timing T7). Specifically, after the new rewrite display data is transferred to the IO register 31, the latch clock CL1 is generated, and the data in the IO register 31 is copied to the latch 1 circuit 32. As a result, new rewritten display data is stored in the latch 1 circuit 32 of the EINK driver 30.

  As described above, the microcomputer 20 executes steps ST12 to ST14 to separate the currently displayed data and the new rewritten display data which are collectively input into the original two display data, and to latch the EINK driver 30. The first circuit 32 and the second latch circuit 33 are sequentially written.

  Next, the microcomputer 20 outputs a display rewrite command in response to the command R36 of the EINK driver 30, and the EINK driver 30 executes display rewrite driving (FIG. 4: step ST15, FIG. 5: timing T8). This display rewrite command sets a predetermined drive voltage and a predetermined pulse width as a drive waveform, and further compares the display data of the latch 1 circuit 32 and the latch 2 circuit 33 to obtain a predetermined positive or negative drive voltage. This is a command for outputting the selected drive waveform and rewriting the display on the display panel 50. Details of the drive waveform will be described later.

  Next, after a predetermined drive waveform is output for a predetermined time by a display rewrite command, the latch clock CL2 is output, and the display data stored in the latch 1 circuit 32 is copied to the latch 2 circuit 33 (FIG. 5: Timing T9).

  Next, the external device stops transmitting the power carrier after a predetermined time has elapsed (FIG. 4: step ST3).

  Next, when carrier transmission from the external device stops, the power supply voltage from the power supply voltage generation circuit 13 of the power supply circuit 40 decreases and the microcomputer 20 and the EIN driver 30 stop the operation of the IC card 1 with display. The IC card with display 1 is in a power-off state (FIG. 4: step ST16, FIG. 5: timing T10). As a result, each segment electrode SEG of the display panel 50 of the IC card with display 1 has a voltage of 0 V. However, since the display panel 50 is an electrophoretic display element having a memory property, newly rewritten display information continues. Is displayed. As a result, the user can check the display information for a long time even when the IC card with display 1 is in the power-off state.

[Transition of display data and description of operation of drive waveform selection circuit: FIG. 6]
Next, how the display data stored in the IO register 12 of the RFID 10, the RAM 22 of the microcomputer 20, the latch 1 circuit 32 and the latch 2 circuit 33 of the EIN driver 30 change in the above-described display rewriting operation of the IC card 1 with display. An example of how the drive waveform selection circuit 34 operates according to the transition of the display data will be described with reference to FIG.

6A shows the transition of display data stored in each circuit, and FIG. 6B shows an operation example of the drive waveform selection circuit 34. The configuration of the drive waveform selection circuit 34 is referred to FIG. 2, and the timing of each operation is referred to FIG. In addition, it is assumed that the currently displayed data is 8 digits (11111111) and the new rewritten display data is 8 digits (22222222).

  In FIG. 6A, when the RFID 10 collectively receives display data, the currently displayed data (11111111) is input to the upper 8 bytes of the IO register 12, and a new rewrite is performed to the lower 8 bytes. Display data (22222222) is input (timing T2). The upper and lower order of the IO register 12 is not limited, and the number of digits of display data is arbitrary.

  Next, the microcomputer 20 reads the 16-byte display data collectively received from the RFID 10, writes 8 bytes of currently displayed data to the address AD1 of the RAM 22, and writes 8 bytes of new rewritten display data to the address AD2. (Timing T3).

  Next, when the microcomputer 20 reads the currently displayed data at the address AD1 of the RAM 22 and transfers it to the EINK driver 30, the currently displayed data is written to the latch 1 circuit 32 of the EINK driver 30 (timing T4).

  Next, when a dummy drive command is executed by the microcomputer 20, the currently displayed data in the latch 1 circuit 32 is copied to the latch 2 circuit 33 (timing T6).

  Next, when the microcomputer 20 reads out the new rewrite display data at the address AD2 of the RAM 22 and transfers it to the EINK driver 30, the new rewrite display data is written in the latch 1 circuit 32 of the EINK driver 30 (timing T7).

  As a result of the above operation, the new rewrite display data “22222222” is stored in the latch 1 circuit 32 of the EINK driver 30, and the currently displayed data “11111111” is stored in the latch 2 circuit 33. This series of operations is performed under the control of the microcomputer 20.

  Next, when a display rewrite command is output from the microcomputer 20 to the command R36 of the EINK driver 30, the comparison circuit 34a of the EINK driver 30 compares the new rewritable display data with the currently displayed data, for each digit. Is output transition data P1. In this example, the transition data P1 is output as a code indicating that the display data changes from “1” to “2”, and this transition data P1 is input to the decoder circuit 34b (see FIG. 2).

  Next, the decoder circuit 34b receives the transition data P1 and outputs seven rewrite codes C0 to C6 composed of 2 bits. The rewrite codes C0 to C6 correspond to the respective segments of the seven segments of the display panel 50. The rewrite code C0 is the segment S0, the rewrite code C1 is the segment S1, and similarly the rewrite code C6 is the segment S6.

  FIG. 6B shows that when the currently displayed data is the number “1” and the new rewrite display data is the number “2”, the drive waveform selection circuit 34 rewrites the rewrite code C0 corresponding to each segment S0 to S6. An example of how to output .about.C6 is shown. In FIG. 6B, when the currently displayed data is the number “1”, the segments S1 and S2 of the seven segments are displayed in black, and the segments S0, S3, S4, S5, and S6 are displayed in white. When the newly rewritten display is “2”, the seven segments S0, S1, S3, S4, and S6 are displayed in black, and the segments S2 and S5 are displayed in white.

  The decoder circuit 34b built in the drive waveform selection circuit 34 outputs rewrite codes C0 to C6 corresponding to the segments S0 to S6 based on the above information. That is, since the segments S0, S3, S4, and S6 are rewritten from white to black, the rewrite codes C0, C3, C4, and C6 output “1”. Further, since the segment S2 is rewritten from black to white, the rewrite code C2 outputs “2”. Further, since segment S1 is black → black and segment S5 is white → white and display rewriting is not required, rewrite codes C1 and C5 output “0”. As described above, the rewrite codes C0 to C6 output the operation of rewriting each segment as a 2-bit code of “0”, “1”, and “2”.

  Next, the driver circuit 35 inputs the rewrite codes C0 to C6 from the drive waveform selection circuit 34. When the rewrite code is “0”, the segment drive voltage VSEG does not rewrite the display, so the drive voltage 0V. The drive waveform is output. That is, when the rewrite code is “0”, the drive waveform is not output because rewriting is not necessary.

  When the rewrite code is “1”, in order to rewrite the display from white to black, the segment drive voltage VSEG outputs a drive waveform having a positive voltage + V for a predetermined time (as an example, about 200 mS) ( FIG. 5: Drive waveform 1). When the rewrite code is “2”, in order to rewrite the display from black to white, the segment drive voltage VSEG outputs a drive waveform having a negative voltage −V for a predetermined time (FIG. 5: drive waveform). 2).

  As described above, the display-equipped IC card 1 according to the first embodiment of the present invention receives both the currently displayed data and new rewritten data from the external device in the rewriting operation of the display panel 50 by the electrophoretic display element. It is configured to compare the two display data, determine the transition of the display, and rewrite only the display segment that needs to be rewritten from white to black or from black to white. Accordingly, there is no need for a reset operation for temporarily changing the display normally performed to rewrite the display to all white or all black, and an IC card with a display excellent in display quality without display flickering or afterimage is provided. I can do it.

  In addition, it is not necessary to provide a nonvolatile memory such as an EEPROM inside the IC card by inputting the currently displayed data every time the display content is rewritten, so that the circuit scale can be reduced, the IC mounting can be simplified, The display control can be simplified.

  In addition, the currently displayed data and new rewritten display data are input from the external device side in a single reception operation, so that communication with the external device can be carried out in a short time, and operation for the user is possible. An IC card with a display that is easy and easy to use can be provided.

  The two display data input in a lump are separated into the currently displayed data and the new rewritten display data by the built-in microcomputer 20, and the current displayed data and the new rewritten display data are used by using a method called dummy driving. Are sequentially transferred to the EINK driver 30 as separate data. As a result, the EINK driver 30 can use a general-purpose driver IC, so there is no need to develop a dedicated EINK driver, and the IC card with display that can be commercialized in a short period of time is inexpensive. I can do it.

  Since this first embodiment is an IC card with a display for only one-way communication that only transmits display data from an external device, the use example is limited, but with a simple display with excellent display quality. It can be used as an IC card.

Next, the display-equipped IC card 2 according to the second embodiment of the present invention will be described. Since the IC card with display 2 of the second embodiment has the same electrical configuration (FIGS. 1 and 2) and mechanical structure (FIG. 3) as the first embodiment, each element has the same reference numeral. The description of the configuration is omitted, and the following description focuses on the specific operation of the second embodiment.

[Description of Operation of Second Embodiment: FIG. 7]
The outline of the operation of the IC card with display 2 of the second embodiment will be described with reference to the flowchart of FIG. Note that the operation timing of the second embodiment is the same as the timing chart (FIG. 5) of the first embodiment described above, and the basic operation is the same as that described above. As described above, since the electrical configuration of the second embodiment is the same as that of the first embodiment, the configuration will be described with reference to FIGS. Further, the description will be made on the assumption that an external device (not shown) for transmitting a power carrier and display data is arranged outside the IC card with display 2.

  In FIG. 7, a carrier for power with a predetermined frequency is transmitted from an external device that controls the IC card with display 2 (step ST4).

  Next, the IC card with display 2 receives the carrier from the external device by electromagnetic induction by the power supply antenna 15, rectifies the AC signal received by the power supply voltage generation circuit 13 of the RFID 10 and converts it into a DC voltage, and the FRID 10 Then, the microcomputer 20 and the EINK driver 30 are supplied as power supply voltages, and the IC card with display 2 is turned on (step ST20).

  Next, when the IC card 2 with display is turned on, the microcomputer 20 is activated, and a card-specific ID number stored in advance is transmitted from the RFID 10 using the communication antenna 14 (step ST21).

  Next, the external device receives the ID number from the IC card with display 2 and identifies the IC card 2 with display (step ST5).

  Next, when the received ID number can be recognized, the external device proceeds to the next step ST7, and when it cannot be recognized, the external device proceeds to step ST8 to stop the carrier transmission and stop the processing (step ST6).

  Next, in step ST7, the external device modulates the carrier by a predetermined method, and transmits the currently displayed data and the new rewritten display data of the recognized IC card 2 with display. Here, as an example, the display data is configured as 8-byte data in which one digit is 1 byte, and display data of a total of 16 bytes is transmitted.

  Next, the IC card with display 2 receives 16 bytes of display data from an external device by electromagnetic induction by the communication antenna 14 and performs a rewrite operation of new display data. The series of operations is described above. Since this is the same as steps ST11 to ST15 shown in FIG. 4 of the first embodiment, description thereof is omitted (step ST22).

  Next, after elapse of a predetermined time from step ST7, the external device stops transmitting the power carrier (step ST8). The external device may execute step ST8 after receiving a display rewrite end signal from the display-equipped IC card 2.

  Next, in the IC card 2 with a display, when carrier transmission from an external device stops, the power supply voltage from the power supply voltage generation circuit 13 of the RFID 10 decreases, and the microcomputer 20 and the EINK driver 30 stop the operation. The IC card 2 is turned off (step ST23).

As described above, the display-equipped IC card 2 according to the second embodiment rewrites the display data after the ID number is identified by the external device. It becomes possible to identify the IC card and accurately rewrite the display data.

  The display-equipped IC card 2 of the second embodiment can be used for electronic money as an example. At present, electronic money, which is often used in the form of an IC card, cannot be known without going to a store or the like and reading it with a reader in order to know the current balance. However, if the display-equipped IC card 2 of the present invention is used as electronic money, the current balance can be displayed each time payment or charge is made at a store or the like, and the display content of the display content is memory. Therefore, it can be held for a long time. Thereby, the IC card with a display excellent in convenience for the user can be provided. When an IC card with a display is used as electronic money, the RFID 10 has a nonvolatile memory protected by a security function, but is omitted for the sake of simplicity. In this case, the displayed data is stored in the nonvolatile memory during the power-off state, and the displayed data moves from the nonvolatile memory to the RAM of the temporary storage unit when the power is turned on. The procedure for moving is as described above.

[Description of Configuration of Communication System of Third Embodiment: FIG. 8]
Next, as a third embodiment, an example of the configuration of a communication system using the IC card with display of the present invention will be described with reference to FIG. In FIG. 8, reference numeral 2 denotes the IC card with display shown in the second embodiment. The IC card with display 2 includes a display panel 50 using an electrophoretic display element, a communication antenna 14, and a power supply antenna 15.

  Reference numeral 41 denotes a reader / writer that performs power supply and communication of an ID number and display data to the IC card with display 2 without contact. The reader / writer 41 has an antenna 41a for power supply and communication, and is coupled to the communication antenna 14 and the power supply antenna 15 incorporated in the IC card 2 with display by a magnetic flux coupling method.

  Reference numeral 42 denotes a controller that controls the reader / writer, and reference numeral 43 denotes a server that manages and stores ID number identification and display data of the IC card 2 with display.

[Description of Operation of Communication System of Third Embodiment: FIG. 8]
Next, an outline of the operation of the communication system according to the third embodiment will be described with reference to FIG. Note that the display-equipped IC card 2 used in the third embodiment will be described on the assumption that it is an IC card having an electronic money function for identifying an IC card by the ID number shown in the second embodiment. . Accordingly, the operation of the IC card with display 2 is the same as the operation flow shown in FIG. 7, and therefore, the operation as a communication system will be mainly described here.

  In FIG. 8, the controller 42 controls the reader / writer 41 to periodically transmit a carrier from the antenna 41a of the reader / writer 41 and wait for an identifiable IC card response.

  When the IC card 2 with a display receives the carrier from the reader / writer 41 by the power supply antenna 15, the IC card 2 is turned on as described above, and transmits the ID number and a password or the like to the reader / writer 41 as necessary.

  The controller 42 receives the ID number and password of the responding IC card 2 with display from the reader / writer, and sends the information to the server 43 via the Internet or the like.

If the server 43 identifies the received ID number, password, etc. and can correctly recognize the IC card 2 with display, the server 43 performs necessary processing, and then is generated by the currently displayed data of the IC card 1 with display and the processing. The new rewritten display data is transmitted from the reader / writer 41 to the IC card with display 2 via the controller 42. As a result, the display-equipped IC card 1 can receive the currently displayed data and new rewritten display data. Therefore, as described in the first embodiment, when the display data is rewritten, the display panel 50 rewrites the display data. Therefore, it is possible to realize a good display state with no display flicker or afterimage.

[Example of use as electronic money: Fig. 8]
Next, a case where a user (not shown) of the display-equipped IC card 2 used as electronic money charges a predetermined amount to the electronic money will be described with reference to FIG. The user brings the IC card 2 with display close to the reader / writer 41 to turn on the IC card 2 with display, and transmits an ID number or the like to the reader / writer 41.

  Next, after identifying the ID number and performing a series of processes necessary for charging, the server 43 performs the current display data (that is, the current remaining amount) and the new display data that is rewritten by the charge (by the charge). Two display data (added remaining amount) are transmitted from the reader / writer 41 to the IC card 2 with display via the controller 42.

  Thereby, the IC card 2 with a display can display the amount added by charge on the display panel 50 as new display data. Since the display panel 50 is a memory-type electrophoretic display element, the display content does not disappear even if the IC card 2 with display is separated from the reader / writer 41 and the power is turned off. The IC card 2 with display itself can confirm that the charge is executed as described above and the balance of the electronic money is added. The charged remaining amount may be stored in the nonvolatile memory of the RF-ID chip after performing a security process. After that, as in the previous embodiment, the displayed data is stored in the nonvolatile memory during the power-off state, and the displayed data moves from the nonvolatile memory to the RAM of the temporary storage means when the power is turned on.

  As described above, according to the communication system using the IC card with display of the present invention, the two display data of the currently displayed data and the new rewritten display data are displayed on the IC card with display. By transmitting from the writer, it is possible to provide an IC card with a display excellent in display quality that does not cause a flicker or an afterimage when the display is rewritten. In addition, since various functions as an IC card and display contents can be rewritten without contact with an external device, a communication system that is convenient for the user can be provided.

  In FIG. 8, the server 43 may be omitted if the controller 42 has a function of identifying the IC card 2 with display. In the third embodiment, the display-equipped IC card 2 that performs bidirectional communication for transmitting an ID number or the like is used. However, the present invention is not limited to this, and the display-equipped IC card of the first embodiment for one-way communication. 1 may be used. Note that the block diagrams, flowcharts, and the like shown in the embodiments of the present invention are not limited thereto, and can be arbitrarily changed as long as they satisfy the gist of the present invention.

  In this embodiment, the RAM of the microcomputer is used as a temporary storage unit. However, the RFID IO register or the IO register of the microcomputer is used as a temporary storage unit, and the displayed data and new rewritten display data are temporarily stored there. You can keep it. In any of the embodiments, the electrophoretic display element is shown as an example. However, the display element is not limited to this as long as the display element has a memory property. For example, a liquid crystal element having a memory property is used as a display unit. But the same effect can be obtained.

  The IC card with display of the present invention and the communication system using the same are excellent in display quality, and display contents can be rewritten in a non-contact manner, so that it can be used for various electronic money IC cards, credit cards, mileage cards, point cards, etc. Can be used widely.

1, 2 IC card with display 3 Mounting board 10 IC for RFID (RFID)
11 Non-contact IO
12, 21, 31 IO register 13 Power supply voltage generation circuit 14 Data antenna 15 Power supply antenna 20 Microcomputer 22 RAM
30 EIN driver 32 Latch 1 circuit 33 Latch 2 circuit 34 Drive waveform selection circuit 35 Driver circuit 36 Command register (command R)
41 Reader / Writer 41a Antenna 42 Controller 43 Server 50 Display Panel 51 Resin Substrate 53 Microcapsule Surface Layer 54 Adhesive Layer 55 Flexible Printed Circuit Board (FPC)
60 Microcapsule 61 Capsule shell 62 Dispersion medium 63a White particle 63b Black particle COM Common electrode SEG Segment electrode VSEG Segment drive voltage CL1, CL2 Latch clock C0-C6 Rewrite code L1 Latch 1 data L2 Latch 2 data P1 Transition data

Claims (6)

In an IC card with a display provided with a display means having a memory property,
Temporary storage means for temporarily storing displayed data in a power-off state and rewritten display data to be newly rewritten when rewriting the display of the display means;
First temporary storage means for taking out only the data being displayed from the temporary storage means and temporarily storing the data;
Second temporary storage means for extracting and temporarily storing the displayed data from the first temporary storage means,
When the data being displayed is temporarily stored in the first temporary storage means, a dummy drive command is output under a condition that the display content of the display means is not rewritten, and the first temporary storage means Control means for taking out the data being displayed and moving it to the second temporary storage means, and inputting the rewritten display data input to the temporary storage means to the first temporary storage means;
The display-equipped IC card further comprising a drive circuit that compares the displayed data with the rewritten display data and selects a drive waveform necessary for rewriting the display of the display means.   2. The display-equipped IC card according to claim 1, wherein the displayed data and the rewritten display data are collectively input from the outside of the drive circuit to the temporary storage unit.   The non-contact communication circuit for non-contact communication is further provided, and the displayed data and the rewritten display data are collectively input to the temporary storage unit by the non-contact communication circuit. The IC card with a display according to 1 or 2. A nonvolatile memory for storing the data being displayed; the data being displayed is stored in the nonvolatile memory; and the data being displayed is moved from the nonvolatile memory to the temporary storage unit. The IC card with a display according to claim 1 or 2.   The IC card with a display according to any one of claims 1 to 4, wherein the power supply is switched from a power-off state to a power-on state by non-contact power supply. IC card with a display according to any one of claims 1 to 5,
And a reader / writer for inputting the rewritten display data and supplying power to turn on the power by non-contact with the IC card with display.