JP2007121676A - Display controller, display control method, storage medium, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To apply a screen erasure processing, which can satisfy both of secrecy and convenience, to electronic paper. <P>SOLUTION: A power management block 1316 detects a voltage drop of a battery 1319 supplying electric power to a paper display 3. Then when the power management block 1316 detects a voltage drop, a central processing controller 139 determines whether the contents of a property holding section of image data are secret information. When it is determined that the contents are secret information, the central processing controller 139 erases an afterimage displayed on the paper display 3, but when it is determined that the contents are not secret information, the afterimage displayed on the paper display 3 is held. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a suitable control method, storage medium, and program for a display device such as a paper display. It is about.

  Conventionally, a paper display (hereinafter referred to as PD) using a display device such as an electrophoretic display device has a feature that it can hold a displayed image without supplying power.

  However, when the battery information of the paper display runs out while the confidential information is displayed on the paper display, the confidential information remains displayed and cannot be erased, resulting in a problem of confidentiality.

  The following Patent Document 1 describes a measure that the display is deleted when it is detected that the power supply is stopped, or the display is deleted when the battery is removed when the external control unit fails.

Patent Document 2 below describes that display control is performed according to display attributes of a paper display in response to a power-off operation.
JP 2004-69965 A JP 2005-172843 A

  However, the screen may be unconditionally erased when a drop in battery voltage is detected as in the conventional example. In this case, since an image without confidentiality is erased, there is a problem in that the original merit of a paper display that can continue to be displayed even when the remaining battery power is exhausted cannot be enjoyed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to respond to the confidential attribute of displayed data when the voltage of the battery supplied to the electronic paper is low. It is to provide a mechanism that can perform screen erasure processing in a different manner.

  The display control apparatus of the present invention that achieves the above object has the following configuration.

  A display control device for displaying input data on electronic paper, comprising a detecting means for detecting a voltage drop of a battery that supplies electric power to the electronic paper. In addition, when a voltage drop is detected by the detection unit, a determination unit that determines whether the content of the attribute holding unit of the image data is confidential information is provided. Further, when the determination unit determines that the information is confidential information, the afterimage displayed on the electronic paper is erased. When the determination unit determines that the information is not confidential information, the afterimage displayed on the electronic paper is deleted. And control means for holding.

  Further, the display control apparatus displays input data on electronic paper, and includes a detecting unit that detects a voltage drop of a battery that supplies power to the electronic paper. In addition, when a voltage drop is detected by the detection unit, a determination unit that determines whether the content of the attribute holding unit of the image data is confidential information is provided.

Further, when the determination means determines that the information is confidential information, the afterimage displayed on the electronic paper is deleted by a first deletion process,
Control means for erasing the afterimage displayed on the electronic paper by a second erasing process when the judging means judges that the information is not confidential information.

  The display control method of the present invention that achieves the above object has the following configuration.

  A display control method in a display control apparatus for displaying input data on electronic paper, comprising a detection step of detecting a voltage drop in a battery that supplies power to the electronic paper. In addition, when a voltage drop is detected in the detection step, the image data has a determination step of determining whether the content of the attribute holding unit of the image data is confidential information. Further, when the determination step determines that the information is confidential information, the afterimage displayed on the electronic paper is erased. When the determination step determines that the information is not confidential information, the afterimage displayed on the electronic paper is deleted. And a control step for holding.

  Moreover, it is a display control method in the display control apparatus which displays the input data on electronic paper, Comprising: It has the detection step which detects the voltage drop of the battery which supplies electric power to the said electronic paper. In addition, when a voltage drop is detected in the detection step, the image data has a determination step of determining whether the content of the attribute holding unit of the image data is confidential information.

  Further, when the determination step determines that the information is confidential information, the afterimage displayed on the electronic paper is erased by a first erasure process. When the determination step determines that the information is not confidential information, And a control step of erasing the displayed afterimage by the second erasing process.

  According to the present invention, when the voltage of the battery supplied to the electronic paper is low, the display screen is erased according to the confidential attribute of the data to be displayed. There is an effect that it is possible to perform a screen erasing process that is compatible with convenience.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings.

<Description of system configuration>
[First Embodiment]
Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing an example of a display system to which the display device showing the first embodiment of the present invention is applied. This example corresponds to a paper display using an electrophoretic display device or the like, and a display system example using a paper display.

  The system example includes a paper display module 131 and another paper display system module 132.

  In FIG. 1, the paper display module 131 includes a paper display element array 133, a drive backplane 134, a drive circuit (X) 135, and a drive circuit (Y) 136. In addition, a panel controller (not shown) that supplies power and signals to the drive backplane 134, the drive circuit (X) 135, and the drive circuit (Y) 136 may be provided.

  The panel controller 137 may also serve as the panel controller. For temperature compensation control, a temperature detection element (not shown) such as a thermocouple or thermistor may be provided. The paper display module 131 may include a digitizer 138.

  Various methods can be used for the digitizer, such as an electromagnetic induction method, a resistive film method, an optical reading method in which a pen has an image pickup device, a data processing function, and a data transfer function.

  The paper display system module 132 includes a panel control function block. The panel control function block includes a central processing controller 139. In general, a micro processor unit (MPU) or a combination of an MPU and an application specific integrated circuit (ASIC) is used. The panel control function block includes a graphic controller 1310 for controlling the paper display, a panel control block 1311, an input data processor 1312, and the like.

  The communication function block includes an external memory interface 1313 that manages an external memory 1317 that controls exchange with external data, a wired I / F 1314, and an external communication interface of a wireless I / F 1315.

Further, the power management function block 1316 detects a voltage of the battery, detects a decrease in the battery voltage, or supplies a power supply means for securing a voltage necessary for the paper display 3 to operate for a certain period of time when the battery voltage decreases (for example, Capacitors and spare batteries). The power management function block 1316 controls charging / discharging of the battery or converts the battery voltage into an appropriate voltage used in the paper display 3.

  Furthermore, a program for operating the central processing controller 139, a work area for operating the central processing controller 139, image data to be displayed on a paper display, an internal memory 1318 for storing a display information management table of the image data, and the like are provided.

  On the paper display system module 132, an operation system (OS) for operating various applications and application software are mounted. As a result, various appropriate communication protocols, imaging protocols, and input data protocols can be appropriately processed.

  Here, only the common part of the paper display will be described in detail.

  The battery 1319 is used as a power source when the paper display 3 is carried and used, and a secondary battery such as a lithium ion battery is generally used. The battery 1319 can be charged from a charger with the battery removed or from the power management block 1316 via the wired I / F 1314 from the external device 1.

  In addition, this example is an example showing the function, and various variations are conceivable as the hardware configuration.

  For example, the drive circuit (X) 135 and the drive circuit (Y) 136 may be formed monolithically on the drive backplane 134. The same applies to the digitizer 138.

  For example, data transmission / reception between the paper display module 131 and the paper display system module 132 may be either wired or wireless.

  In the case of wireless, the paper display module 131 has a power supply or power generation function or a wireless energy transfer function.

  Here, the paper display module 131 and the paper display system module 132 are shown in a 1: 1 relationship, but the paper display module 131 and the paper display system module 132 may be in an n: 1 relationship.

  The paper display of this embodiment can be used for a display unit of a personal digital assistant (Personal Digital Assistance: PDA). In addition, it can also be used for display units of TabletPC, electronic notebooks, electronic textbooks, document viewers, electronic books, electronic newspapers, and the like.

  Next, a drawing sequence in the paper display 3 will be described.

  Image data is transmitted from the external device 1 or the external device 2 to the paper display 3. The central processing controller 139 captures image data via the wired I / F 1314 or the wireless I / F 1315. Then, it is stored in the internal memory 1318 or the external memory 1317. Here, it is assumed that the internal memory 1318 has a smaller capacity than the external memory 1317.

  If the image data cannot be stored in the internal memory 1318, the image data is temporarily stored in the external memory 1317. For the external memory 1317, a removable memory card such as an SD card or a compact flash (registered trademark) card can be used. The image data stored in the external memory 1317 can be read and displayed.

  The central processing controller 139 reads image data from the internal memory 1318 or the external memory 1317 and sends it to the graphic controller 1310. The graphic controller 1310 performs image data processing and creates display data.

  The graphic controller 1310 transmits display data to the paper display module 131 via the panel interface 137.

  Further, a timing control signal such as a horizontal synchronizing signal and a vertical synchronizing signal is transmitted from the panel control block 1311 to the paper display module 131. Display is performed by outputting a data signal from the drive circuit (X) 135 and a scan signal from the drive circuit (Y) 136 based on the display data and the timing control signal.

  Next, the operation when an instruction is given with the operation button will be described.

  Button pressing information is input to the input data processor 1312 from an operation button (not shown) of the paper display 3, interpreted by the central processing controller 139, and a command for displaying a specific page is input. Upon receiving the command, the central processing controller 139 reads the image data of the designated page from the internal memory 1318 or the external memory 1317 and sends it to the graphic controller 1310.

  The graphic controller 1310 performs image data processing and creates display data. The graphic controller 1310 transmits display data to the paper display module 131 via the panel interface 137.

  Further, a timing control signal such as a horizontal synchronizing signal and a vertical synchronizing signal is transmitted from the panel control block 1311 to the paper display module 131. Based on the display data and the timing control signal, a data signal is output from the drive circuit (X) 135 and a scan signal is output from the drive circuit (Y) 136 to perform display.

  Next, the operation when pen input is performed on a paper display will be described.

  Pen position data is created by the digitizer 138 and the input data processor 1312. The central processing controller 139 stores the pen position data in the internal memory 1318 as image data. At the same time, it can be sent to the graphic controller 1310 to display the position of the pen. Then, the pen position data is periodically created and the operation is repeated. In this way, it is possible to know which position is indicated on the paper display screen. Then, the screen is displayed in the same manner as instructed by the operation button.

  FIG. 2 is a view for explaining the structure of display data stored in the internal memory 1318 or the external memory 1317 shown in FIG.

  In FIG. 2, when the display data is confidential information bit 21 and “1” is set, this indicates that the display data is data for which confidentiality is required. When the display data is confidential information bit 21 “0”, it indicates that the display data is data for which confidentiality is not required.

  In the present embodiment, the central processing controller 139 detects a voltage drop of the battery 1319 based on a control procedure shown in FIG. In this case, it is determined whether or not the display data has the confidential information bit 21 “1”. When the confidential information bit 21 is “1”, the display data displayed on the paper display 3 is deleted. Specifically, the voltage applied to the drive circuits 133 and 136 is controlled to alternately apply + 15V and −15V. Thereby, the afterimage, which is a characteristic of the paper display 3, is completely erased.

  When the confidential information bit 21 is “0” for the display data, a process for holding the display data displayed on the paper display 3 is performed. Specifically, the voltage applied to the drive circuits 133 and 136 is specifically “0” V.

  FIG. 3 is a diagram showing an example of a display information management table secured in the internal memory 1318 or the external memory 1317 shown in FIG.

  FIG. 4 is a diagram for explaining the data structure of confidential information held in the internal memory 1318 shown in FIG.

  In FIG. 4, TAB is a display information management table that manages the image number of the display data and the airtight information bit as a pair.

  As shown in FIG. 2, the confidential information bit included in a part or the top of the display data is stored in the internal memory 1318 or the external memory 1317 with 1 set. Alternatively, as shown in FIG. 3, the display information management table is held in the internal memory 1318 or the external memory 1317, and the image No. to be displayed is displayed. And store confidential information bit.

  When the external memory 1317 is attached to the paper display 3, the image data is transmitted to the external memory after instructing that it is confidential information when the image data is transmitted from the external device 3 (not shown).

  Similarly to the above, it is instructed that the corresponding image data is confidential information with the data structure as shown in FIG. 2 or FIG. Further, when the operator is displaying the image data, it can be instructed by an operation button or a pen input that the currently displayed image is confidential information. In that case, the confidential information bit in the internal memory 1318 is set to 1 with the data structure as shown in FIG. 4, or the confidential information bit corresponding to the image currently displayed in the data structure as shown in FIGS. You can stand up to 1.

  Further, the operator can instruct the confidential information by selecting from the file name of the image data, the icon, or the list of image data by the operation button or pen input of the paper display 3. It is also possible to release the confidential information bit by entering the administrator mode after authentication by an authentication means such as a password.

FIG. 5 is a flowchart showing an example of a first display control procedure in the display control apparatus according to the present invention.
In addition, S101-S105 show each step. Each step is realized by the central processing controller 139 loading a program from the internal memory to the RAM and executing the program.

  First, image data is transmitted from the external device 1 or the external device 2 to the paper display 3 in a state where the charged battery 1319 is attached to the paper display 3 and the power is turned on.

  At that time, the confidential data bit is set to “1” for the image data instructed by the operator and is handled as confidential information image data.

  For example, when it is transmitted from the external device 1 or the external device 2 to the paper display 3, it is transmitted after instructing that it is confidential information. Then, as shown in FIG. 2, it is stored in the internal memory 1318 or the external memory 1317 with the confidential information bit included in a part or the top of the display data set to “1”. Alternatively, as shown in FIG. 3, the display information management table is held in the internal memory 1318 or the external memory 1317, and the image No. to be displayed is displayed. And store confidential information bit.

  When the external memory 1317 is attached to the paper display 3, the image data is transmitted to the external memory after instructing that it is confidential information when the image data is transmitted from the external device 3 (not shown).

  Similarly to the above, it is instructed that the corresponding image data is confidential information with the data structure as shown in FIG. 2 or FIG.

  Further, when the operator is displaying the image data, it can also be instructed by the operation button or pen input that the currently displayed image is confidential information. In that case, the confidential information bit in the internal memory 1318 is set to “1” in the data structure as shown in FIG. 4, or the confidential information corresponding to the image currently displayed in the data structure as shown in FIG. 2 or FIG. You can set bit to 1.

  Further, the operator can instruct the confidential information by selecting from the file name of the image data, the icon, or the list of image data by the operation button or pen input of the paper display 3.

  It is also possible to release the confidential information bit by entering the administrator mode after authentication by an authentication means such as a password.

  In step S101, the operator removes the paper display 3 from the external device 1 and carries it or displays a carried image outside the proximity range of the external device 2 to perform a normal operation. Then, the process proceeds to step S102.

  In step S102, the power management block 1316 constantly monitors the voltage of the battery 1319, and determines whether an interrupt signal is generated for the central processing controller 139 when the battery voltage falls below a predetermined value.

  For example, if a lithium ion battery is used as a battery and a voltage of 3.7 V is present at the completion of charging, and if a specified value (threshold value) for determining that the remaining battery level is reduced is 3.2 V, the battery voltage is 3 When 2V or less, an interrupt signal is generated.

  If it is determined that no interrupt signal has been generated, the process returns to step S101.

  On the other hand, if it is determined in step S102 that this is due to a decrease in battery voltage, the process proceeds to step S103.

  In step S102, the power management block 1316 provides power supply means (for example, a capacitor or a spare battery) that secures a voltage necessary for the paper display 3 to operate for a certain period of time when the battery voltage drops.

  When it is determined in step S102 that the battery voltage is low, the central processing controller 139 refers to the confidential information bit associated with the image currently displayed in the external memory 1317 or the internal memory 1318.

  Note that the structure of the attribute holding unit that represents whether the image data is confidential information can take a data structure such as the confidential information bit shown in FIGS. 2, 3, and 4.

  In step S103, it is determined whether or not the confidential information bit of the currently displayed image is “1”. If it is determined that the confidential information bit is “1”, the process proceeds to step S104.

  On the other hand, if it is determined in step S103 that the confidential information bit is not “0”, the process proceeds to step S105.

  In step S104, since the currently displayed image is determined to be confidential information, control for deleting the screen of the paper display 3 is performed, and this processing is terminated.

  Note that the screen erasure control in step S104 is performed by the central processing controller 139 controlling the drive circuits 135 and 136 so that all the pixels on the screen are white via the graphic controller 1310.

  The paper display 3 in the present embodiment changes the voltage value to be applied at the gradation to be displayed next with respect to the gradation of the currently displayed image as a feature of display driving. At this time, the drive circuits 135 and 136 apply a voltage for changing from the currently displayed gradation to white to each pixel.

  For example, if the pixel is changed from black to white, -15V is applied. If the pixel is changed from white to black, +15 V is applied. Also, 0V is applied to keep the pixel unchanged.

  Here, as a characteristic of the paper display 3, since an afterimage is likely to remain behind the LCD, control may be performed so that the afterimage does not remain.

  For example, after all the pixels are rewritten to white, all the pixels are erased to become black. After such rewriting control is performed a predetermined number of times, for example, three times, the image is rewritten to white.

  On the other hand, it may be completely rewritten several times whether all pixels are white or black.

  After erasing the screen in this way, the central processing controller 139 enters a state where the operation of the paper display 3 is stopped. In this way, the screen is erased if confidential information is being displayed when the remaining battery level is low.

  On the other hand, if it is determined in step S103 that confidential information is not being displayed, in step S105, control is performed to hold the screen of the paper display 3 via the drive circuits 135 and 136, and this process ends.

  Specifically, the central processing controller 139 controls the drive circuits 135 and 136 so as to hold the screen pixels via the graphic controller 1310.

  Then, the central processing controller 139 enters a state where the operation of the paper display 3 is stopped.

  Note that the display image can be held even when there is no power source as a feature of the paper display 3, so that the image can be viewed even without the power source, and convenience can be improved.

  As described above, in the present embodiment, when the data input by the central controller 139 is displayed on the paper display 3, the power management block 1316 detects a voltage drop of the battery 1319 that supplies power to the paper display 3. When the power management block 1316 detects a voltage drop, the confidential information bit as shown in FIG. 4 is stored in the internal memory to determine whether the content of the attribute holding unit of the image data is confidential information. Determine whether or not. If it is determined that the power management block 1316 is, the central processing controller 139 erases the afterimage displayed on the paper display 3 by the first erasing process (step S104 shown in FIG. 5). If it is determined that the confidential information bit is “0”, the central processing controller 139 performs control to hold the afterimage displayed on the paper display 3 (step S105 shown in FIG. 5).

  According to the first embodiment, when the remaining amount of the battery 1319 decreases to a predetermined threshold level, the screen is erased if the paper display 3 is displaying confidential information, and the screen is not erased otherwise. Execute. As a result, by deleting the display image, the confidentiality is increased when confidentiality is required, and when the confidentiality is not required, the display content is retained, thereby enabling display utilizing the characteristics of the paper display 3. Can be provided to users. Therefore, convenience can be improved by responding to a display request that effectively utilizes the characteristics of the paper display.

[Second Embodiment]
In the present embodiment, by considering the afterimage characteristics of the paper display 3, different screen erasure control is executed according to the holding state of confidential information, so that image data to be displayed after erasing that is set in advance after erasing the screen. Is displayed. Hereinafter, the embodiment will be described in detail.

  FIG. 6 is a flowchart showing an example of a second display control procedure in the display control apparatus according to the present invention.

  S201 to S206 indicate each step. Each step is realized by the central processing controller 139 loading a program from the internal memory to the RAM and executing the program.

  First, image data is transmitted from the external device 1 or the external device 2 to the paper display 3 in a state where the charged battery 1319 is attached to the paper display 3 and the power is turned on. At this time, the confidential data bit is set to 1 for the image data instructed by the operator and is handled as confidential information image data.

  For example, when it is transmitted from the external device 1 or the external device 2 to the paper display 3, it is transmitted after instructing that it is confidential information. Then, as shown in FIG. 2, it is stored in the internal memory 1318 or the external memory 1317 with the confidential information bit included in a part or the top of the display data set to “1”. Alternatively, as shown in FIG. 3, the display information management table is held in the internal memory 1318 or the external memory 1317, and the image No. to be displayed is displayed. And store confidential information bit.

  When the external memory 1317 is attached to the paper display 3, the image data is transmitted to the external memory after instructing that it is confidential information when the image data is transmitted from the external device 3 (not shown).

  Similarly to the above, it is instructed that the corresponding image data is confidential information with the data structure as shown in FIG. 2 or FIG. Further, when the operator is displaying the image data, it can be instructed by an operation button or a pen input that the currently displayed image is confidential information. In that case, the confidential information bit in the internal memory 1318 is set to 1 in the data structure as shown in FIG. 4, or the image currently displayed in the data structure as shown in FIGS. 2 and 3 is confidential information. Instruct.

  Further, the operator can instruct the confidential information by selecting from the file name of the image data, the icon, or the list of image data by the operation button or pen input of the paper display 3. It is also possible to release the confidential information bit by entering the administrator mode after authentication by an authentication means such as a password.

  First, in step S201, the operator removes the paper display 3 from the external device 1 and carries it, or carries it outside the proximity range of the external device 2 and performs a normal operation. Then, the process proceeds to step S202.

  The power management block 1316 constantly monitors the voltage of the battery 1319, and generates an interrupt signal to the central processing controller 139 when the battery voltage falls below a specified value (threshold value).

  For example, if a lithium ion battery is used as a battery and a voltage of 3.7 V is present at the completion of charging, and if a specified value for determining that the remaining battery level is reduced is 3.2 V, the battery voltage becomes 3.2 V or less. An interrupt signal is generated.

  In step S202, it is determined whether an interrupt signal is generated due to a battery voltage drop. If it is determined that no interrupt signal has been generated, the process returns to step S201.

  On the other hand, if it is determined in step S202 that an interrupt signal has been generated, the process proceeds to step S203.

  The power management block 1316 provides power supply means (for example, a capacitor or a spare battery) that secures a voltage necessary for the paper display 3 to operate for a certain period of time when the battery voltage drops.

  If it is determined in step S202 that the battery voltage is low, the central processing controller 139 refers to the confidential information bit associated with the currently displayed image in the external memory 1317 or the internal memory 1318.

  Note that the structure of the attribute holding unit that represents whether the image data is confidential information can take a data structure such as the confidential information bit shown in FIGS. 2, 3, and 4.

  In step S203, it is determined whether or not the confidential information bit of the currently displayed image is set to “1”.

  If it is determined that the confidential information bit of the currently displayed image is “1”, it is determined in step S204 that the currently displayed image is confidential information, so that an afterimage appears on the screen of the paper display 3. The drive circuits 135 and 136 are controlled so as to be erased so as not to remain. Here, erasing so that no afterimage remains on the screen of the paper display 3 is a first erasing process.

  Here, since the afterimage tends to remain as a characteristic of the paper display, such control is performed.

  Specifically, the central processing controller 139 controls the drive circuits 135 and 136 so that all the pixels on the screen are white via the graphic controller 1310, thereby erasing the screen display contents.

  Further, as a characteristic of display driving of the paper display 3, the voltage value to be applied at the gradation to be displayed next is changed with respect to the gradation of the currently displayed image, so that the gradation from the currently displayed gradation is changed to white. A voltage for changing is applied to each pixel.

  For example, if the pixel is changed from black to white, -15V is applied. If the pixel is changed from white to black, + 15V is applied. Also, 0V is applied to keep the pixel unchanged.

  In this way, after all the pixels of the paper display 3 are rewritten to white pixels, the central processing controller 139 then performs control to erase all the pixels on the screen through the graphic controller 1310.

  The image is rewritten to white after the above rewriting is performed a predetermined number of times, for example, three times. Alternatively, it may be completely rewritten whether all pixels are white or black.

  In the present embodiment, normal erasure is performed by rewriting all pixels of the paper display 3 to white only once. In this case, an afterimage may remain on the paper display 3.

  In this way, when the remaining battery level is low, if the confidential information is being displayed, the screen is erased so that no afterimage remains.

  On the other hand, if it is determined in step S203 that the confidential information bit of the currently displayed image is “1”, the screen of the paper display 3 is displayed by controlling the drive circuits 135 and 136 in step S205. Control to erase normally. Here, erasing the screen of the paper display 3 normally is the second erasing process.

  Specifically, the central processing controller 139 controls the drive circuits 135 and 136 to erase all the pixels on the screen through the graphic controller 1310, and the process proceeds to step S206.

  Next, in step S206, control for displaying a screen according to the setting is performed, and this process is terminated.

  In step S206, if it is determined in step S203 that confidential information is being displayed, the screen is erased in step S204 with control that no afterimage remains. As a result, the central processing controller 139 enters a state in which the operation of the paper display 3 is stopped without doing anything.

  On the other hand, if it is determined in step S203 that confidential information is not being displayed, the screen is erased by normal control in step S205. However, in order to improve convenience, an image (for example, an initial value) is selected. Screen, wallpaper, timetable, etc.).

  Thereafter, the central processing controller 139 enters a state where the operation of the paper display 3 is stopped.

  As described above, in the present embodiment, when the data input by the central controller 139 is displayed on the paper display 3, the power management block 1316 detects a voltage drop of the battery 1319 that supplies power to the paper display 3. When the power management block 1316 detects a voltage drop, the confidential information bit as shown in FIG. 4 is stored in the internal memory to determine whether the content of the attribute holding unit of the image data is confidential information. Determine whether or not. If it is determined that the power management block 1316 is, the central processing controller 139 erases the afterimage displayed on the paper display 3 in the first erasure process (step S204 shown in FIG. 6). If it is determined that the confidential information bit is “0”, the central processing controller 139 performs control to erase the afterimage displayed on the paper display 3 in the second erasing process (step S205 shown in FIG. 6). .

  Note that the first erasing process is a complete erasing process in which voltages of different signs are applied to the pixels of the electronic paper a plurality of times to erase the entire surface of the pixels. Further, in the second erasing process, a normal erasing process is performed in which a voltage having a different sign is applied to the pixel of the electronic paper to erase the entire pixel surface.

  Further, the central processing controller 139 performs control (step S206 shown in FIG. 6) to display preset data (for example, wallpaper, timetable) after the normal erasing process by the second erasing process.

  According to the second embodiment, when the remaining amount of the battery 1319 is reduced to the threshold level, the confidentiality can be enhanced by deleting the screen by the control in which no afterimage remains if the confidential information is being displayed.

  On the other hand, if the confidential information is not being displayed, the screen is erased by normal control, and then an image (for example, initial screen, wallpaper, timetable, etc.) is displayed according to the setting, thereby responding to a display request on the display. This can improve the convenience.

[Third Embodiment]
In the first and second embodiments, the case where the entire display screen is erased has been described. However, as described in Patent Document 2, confidential information is managed in units of pixels. And when the voltage drop of the battery 1319 is detected, it is good also as a structure which controls an erasure | elimination mode by a confidential information display area and another display area.

[Fourth Embodiment]
The configuration of a data processing program that can be read by the information processing apparatus according to the present invention will be described below with reference to the memory map shown in FIG.

  FIG. 7 is a diagram illustrating a memory map of a storage medium that stores various data processing programs readable by the information processing apparatus according to the present invention.

  Although not particularly illustrated, information for managing a program group stored in the storage medium, for example, version information, creator, etc. is also stored, and information depending on the OS on the program reading side, for example, a program is identified and displayed. Icons may also be stored.

  Further, data depending on various programs is also managed in the directory. In addition, a program for installing various programs in the computer, and a program for decompressing when the program to be installed is compressed may be stored.

  The functions shown in FIGS. 5 and 6 in this embodiment may be performed by a host computer by a program installed from the outside. In this case, the present invention is applied even when an information group including a program is supplied to the output device from a storage medium such as a CD-ROM, a flash memory, or an FD, or from an external storage medium via a network. Is.

  As described above, the storage medium storing the software program code for realizing the functions of the above-described embodiments is supplied to the system or apparatus. It goes without saying that the object of the present invention can also be achieved by the computer (or CPU or MPU) of the system or apparatus reading and executing the program code stored in the storage medium.

  In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium storing the program code constitutes the present invention.

  Therefore, as long as it has the function of the program, the form of the program such as an object code, a program executed by an interpreter, or script data supplied to the OS is not limited.

  As a storage medium for supplying the program, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card, ROM, DVD, etc. Can be used.

  In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.

  As another program supply method, a browser on a client computer is used to connect to an Internet home page. Then, the computer program itself of the present invention or a compressed file including an automatic installation function can be downloaded from the homepage by downloading it to a recording medium such as a hard disk. It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server, an ftp server, and the like that allow a plurality of users to download a program file for realizing the functional processing of the present invention on a computer are also included in the claims of the present invention.

  In addition, the program of the present invention is encrypted, stored in a storage medium such as a CD-ROM, distributed to users, and key information for decryption is downloaded from a homepage via the Internet to users who have cleared predetermined conditions. Let It is also possible to execute the encrypted program by using the key information and install the program on a computer.

  In addition, the functions of the above-described embodiments are not only realized by executing the program code read by the computer. For example, based on an instruction of the program code, an OS (operating system) running on the computer performs part or all of the actual processing. Needless to say, the process includes the case where the functions of the above-described embodiments are realized.

  Further, the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. After that, based on the instruction of the program code, the CPU of the function expansion board or function expansion unit performs part or all of the actual processing, and the processing of the above-described embodiment is realized by the processing. Needless to say.

  The present invention is not limited to the above embodiments, and various modifications (including organic combinations of the embodiments) are possible based on the spirit of the present invention, and these are excluded from the scope of the present invention. is not.

  Although various examples and embodiments of the present invention have been shown and described, those skilled in the art will not limit the spirit and scope of the present invention to the specific description in the present specification.

It is a block diagram which shows an example of the display system to which the display apparatus which shows the 1st Embodiment of this invention is applied. It is a figure explaining the structure of the display data stored in the internal memory shown in FIG. 1, or an external memory. It is a figure which shows an example of the display information management table ensured in the internal memory shown in FIG. 1, or an external memory. It is a figure explaining the data structure of the confidential information hold | maintained in the internal memory shown in FIG. It is a flowchart which shows an example of the 1st display control procedure in the display control apparatus which concerns on this invention. It is a flowchart which shows an example of the 2nd display control procedure in the display control apparatus which concerns on this invention. It is a figure explaining the memory map of the storage medium which stores the various data processing program which can be read with the display control apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 External device 2 External device 3 Paper display 131 Paper display module 132 Paper display system module 133 Paper display element array 134 Drive back plane 135 Drive circuit (X)
136 Drive circuit (Y)
139 Central processing controller 1311 Panel control block 1317 External memory 1318 Internal memory 1319 Battery

Claims (12)

A display control device for displaying input data on electronic paper,
Detecting means for detecting a voltage drop of a battery for supplying electric power to the electronic paper;
A determination unit that determines whether the content of the attribute holding unit of the image data is confidential information when a voltage drop is detected by the detection unit;
When the determination means determines that the information is confidential information, the afterimage displayed on the electronic paper is erased. When the determination means determines that the information is not confidential information, the afterimage displayed on the electronic paper is retained. Control means;
A display control device comprising: A display control device for displaying input data on electronic paper,
Detecting means for detecting a voltage drop of a battery for supplying electric power to the electronic paper;
A determination unit that determines whether the content of the attribute holding unit of the image data is confidential information when a voltage drop is detected by the detection unit;
When the determination means determines that the information is confidential information, the afterimage displayed on the electronic paper is erased by the first erasure process, and when the determination means determines that the information is not confidential information, it is displayed on the electronic paper. Control means for erasing the remaining afterimage in the second erasure process;
A display control device comprising: 3. The display control apparatus according to claim 2, wherein the first erasing process is a complete erasing process in which a voltage of a different sign is applied to the pixel of the electronic paper a plurality of times to erase the entire pixel surface. 3. The display control apparatus according to claim 2, wherein the second erasing process is a normal erasing process in which a voltage having a different sign is applied to the pixel of the electronic paper to erase the entire surface of the pixel. 5. The display control apparatus according to claim 2, wherein the control unit displays preset data after the normal erasing process by the second erasing process. A display control method in a display control device for displaying input data on electronic paper,
A detection step of detecting a voltage drop of a battery that supplies power to the electronic paper;
A determination step of determining whether the content of the attribute holding unit of the image data is confidential information when a voltage drop is detected by the detection step;
When the determination step determines that the information is confidential information, the afterimage displayed on the electronic paper is erased. When the determination step determines that the information is not confidential information, the afterimage displayed on the electronic paper is retained. Control steps;
A display control method comprising: A display control method in a display control device for displaying input data on electronic paper,
A detection step of detecting a voltage drop of a battery that supplies power to the electronic paper;
A determination step of determining whether the content of the attribute holding unit of the image data is confidential information when a voltage drop is detected by the detection step;
When it is determined that the determination step is confidential information, the afterimage displayed on the electronic paper is erased by the first erasure process, and when the determination step is determined not to be confidential information, it is displayed on the electronic paper. A control step for erasing the remaining afterimage in the second erasure process;
A display control method comprising: The display control method according to claim 7, wherein the first erasing process is a complete erasing process in which a voltage of a different sign is applied to the pixel of the electronic paper a plurality of times to erase the entire surface of the pixel. The display control method according to claim 7, wherein the second erasing process is a normal erasing process in which a voltage of a different sign is applied to the pixel of the electronic paper to erase the entire pixel surface. The display control method according to claim 7, wherein the control step displays preset data after the normal erasing process by the second erasing process. A computer-readable storage medium storing a program for causing a computer to execute the display control method according to claim 6. A program for causing a computer to execute the display control method according to claim 6.

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