JP2012233934A - Image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce consumption power without giving a discomfort to an observer.SOLUTION: An image display device includes: a storage part 12 for storing image data; a display part 6 having a memory property for displaying an image based on the image data when a voltage for displaying the image data is applied and maintaining the display of the image after completing the application of the voltage; a drive part 24 for driving the display part; and an input part 20 for inputting an instruction to perform a display of the display part while saving power. The drive part switches display contents in a partial area of the display part by applying the voltage to the partial area when the instruction is input.

Description

  The present invention relates to an image display device.

  2. Description of the Related Art Conventionally, an electrophoretic display device that reduces power consumption when updating an image displayed on a display unit is known (see, for example, Patent Document 1). According to this electrophoretic display device, the power consumption at the time of image update can be reduced by reducing the value of the voltage applied to the display unit at the time of image update.

JP 2009-237273 A

  However, in the above-described electrophoretic display device, there is a problem that the image quality of an image displayed on the display unit deteriorates when the value of the voltage applied to the display unit is reduced.

  An object of the present invention is to reduce power consumption without causing an observer to feel uncomfortable.

  An image display device according to the present invention displays a storage unit that stores image data and an image based on the image data when a voltage for displaying the image data is applied, and after the application of the voltage is completed A display unit having a memory function for maintaining the display of the image, a drive unit for driving the display unit, and an input unit for inputting an instruction to display the display unit with power saving, When the instruction is input, the display contents in the partial area are switched by applying the voltage to the partial area of the display unit.

  In addition, the image display device of the present invention displays the image when a storage unit that stores image data and a voltage for displaying an image based on the image data are applied, and the application of the voltage is finished. A display unit having a memory function to maintain display of the image later; a drive unit that drives the display unit; and an input unit that inputs an instruction to display the display unit with power saving, and the drive unit Is characterized in that, when the instruction is input, the method for switching the image displayed on the display unit is changed.

  According to the present invention, it is possible to reduce power consumption without giving an uncomfortable feeling to an observer.

It is a perspective view which shows the front surface of the image display apparatus which concerns on 1st Embodiment. It is a block diagram which shows the system configuration | structure of the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the electricity supply area | region in the display part of the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the battery residual amount, time, and a display part in the image display apparatus which concerns on 1st Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 2nd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 3rd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 3rd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 3rd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 3rd Embodiment. It is a figure which shows the image displayed on the remaining amount of battery, time, and a display part in the image display apparatus which concerns on 3rd Embodiment. It is a figure which shows the image displayed in the residual amount of a battery, the time, and the display part in the image display apparatus which concerns on 4th Embodiment. It is a figure which shows the image displayed in the residual amount of a battery, the time, and the display part in the image display apparatus which concerns on 4th Embodiment. It is a figure which shows the image displayed in the residual amount of a battery, the time, and the display part in the image display apparatus which concerns on 4th Embodiment. It is a figure which shows the image displayed in the residual amount of a battery, the time, and the display part in the image display apparatus which concerns on 4th Embodiment. It is a figure which shows the image displayed in the residual amount of a battery, the time, and the display part in the image display apparatus which concerns on 4th Embodiment.

  Hereinafter, an image display apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an appearance of the image display apparatus according to the first embodiment of the present invention. The image display device 2 includes a device main body 4 made of glass, plastic, or the like, and a display unit 6 having a memory property (for example, displaying an image when a predetermined voltage is applied to the front surface of the device main body 4 (for example, An electrophoretic electronic paper that displays an image by an electrophoretic element including a plurality of microcapsules in which a transparent liquid and particles are enclosed. Here, since the display unit 6 has a memory property, the image displayed on the display unit 6 can be continuously displayed even when no voltage is applied.

  On the upper surface of the apparatus body 4, a power switch 8 that switches on / off the power of the image display apparatus 2 and a slide show button 10 that displays images in a slide show on the display unit 6 are provided. Further, a memory card slot 14 into which a memory card 12 storing image data is inserted is provided on one side surface of the apparatus body 4.

  FIG. 2 is a block diagram showing a system configuration of the image display apparatus 2 according to the first embodiment. The image display device 2 includes a CPU 20 that comprehensively controls each unit of the image display device 2. The CPU 20 includes an operation unit 22 including the power switch 8 and the slide show button 10 described above, a drive unit 24 that drives the display unit 6, a ROM 28 that stores a program for executing a slide show display on the display unit 6, and image data. A RAM 30 that temporarily stores, a VRAM 32 that stores image data of an image to be displayed on the display unit 6, a memory card slot 14 that attaches / detaches a memory card 12 that stores image data, and a battery 34 that controls power supply to each unit. A wireless communication unit 38 that transmits and receives image data and the like between the power control unit 36 and an external device is connected.

  FIG. 3 is a diagram illustrating an energization region to which a voltage is applied in the display unit 6 of the image display device 2 according to the first embodiment. The display unit 6 is divided into four energized regions, an energized region 40, an energized region 42, an energized region 44, and an energized region 46. When the display content on the display unit 6 is switched, the CPU 20 A predetermined voltage is applied to the energized region whose display content is to be switched. For example, when switching the image displayed on the display unit 6 to the next image in the normal display mode in which the normal slide show display is performed, the CPU 20 causes the drive unit 24 to display the next image for all energized areas. A predetermined voltage is applied. In addition, when the display content on the display unit 6 is switched in the power saving display mode in which the slide show display is performed with low power consumption, a predetermined voltage is applied to a part of the energized region. For example, when switching the image displayed in the energization region 40 to the next image, the CPU 20 applies a predetermined voltage for displaying the next image to the energization region 40 by the drive unit 24.

  Next, processing of the image display device 2 according to the first embodiment will be described with reference to the drawings. First, when the power switch 8 is pressed to turn on the power, the CPU 20 starts detecting the remaining amount of the battery 34 via the power control unit 36, and the remaining amount of the battery 34 is set to a predetermined value ( For example, it is determined whether or not it is 30% or more at full charge. When the value of the remaining amount of the battery 34 is equal to or greater than a predetermined value (see the diagram shown in the upper part of FIG. 4), the CPU 20 sets the display mode of the image display device 2 to the normal display mode.

  Here, when the slide show button 10 is pressed by the operator, the CPU 20 first selects the image data of the image displayed on the display unit 6 from the image data stored in the memory card 12, for example, the file name “001”. The image data is read out from the RAM 30 and stored in the VRAM 32. Next, the CPU 20 applies a predetermined voltage for displaying an image based on the image data to the display unit 6 by the drive unit 24, and for example, as shown in the lower part of FIG. An image 50 based on the image data “001” is displayed on the display unit 6 (current time 0:00). Here, the unit time for displaying one image in the slide show display is 1 minute.

  Next, when one minute, which is a unit time, has elapsed since the first display of the image on the display unit 6 (current time 01:00, see FIG. 5), the CPU 20 displays the next image to be displayed from the memory card 12. Image data, for example, image data with the file name “002” is read out, temporarily stored in the RAM 30, and then written in the VRAM 32. Next, the CPU 20 applies a predetermined voltage for displaying this image data to all energized regions of the display unit 6 by the drive unit 24, and displays the image as shown in the lower part of FIG. The image 50 displayed in the part 6 is switched to the image 52 based on the image data of the file name “002”.

  Here, when the remaining amount of the battery 34 decreases and the value of the remaining amount of the battery 34 becomes smaller than a predetermined value (see the diagram shown in the upper part of FIG. 6), the CPU 20 displays the display mode of the image display device 2. Switch from normal display mode to power saving display mode.

  Next, when one minute, which is a unit time, has elapsed since the last image switching in the normal display mode (current time 01:00, see FIG. 5) (current time 02:00, see FIG. 7), The CPU 20 reads, for example, four pieces of image data of file names “003”, “004”, “005”, and “006” as the next image data to be displayed on the display unit 6 from the memory card 12 and these images. Data is temporarily stored in the RAM 30 and then written in a predetermined area of the VRAM 32. For example, the image data with the file name “003” is written in an area corresponding to the energized area 40 (see FIG. 3) in the VRAM 32. Similarly, the image data with the file name “004” is energized in the area corresponding to the energized area 42, the image data with the file name “005” is energized in the area corresponding to the energized area 44, and the image data with the file name “006” is energized. Each is written in an area corresponding to the area 46.

  Next, the CPU 20 applies a predetermined voltage for displaying an image based on the plurality of image data to the display unit 6 by the driving unit 24, for example, as illustrated in the lower part of FIG. The image 52 displayed on the display unit 6 is switched to four images of an image 54, an image 56, an image 58, and an image 60.

  Next, when 1 minute which is a unit time has elapsed (current time 03:00, see FIG. 8), the CPU 20 switches one of the plurality of images displayed on the display unit 6. For example, the CPU 20 reads out the image data with the file name “007” from the memory card 12, temporarily stores it in the RAM 30, and then writes it in an area corresponding to the energized area 40 (see FIG. 3) in the VRAM 32.

  Next, the CPU 20 applies a predetermined voltage for displaying an image based on this image data to the energized region 40 of the display unit 6 by the drive unit 24, for example, as shown in the lower part of FIG. Then, the image 54 displayed in the energization region 40 of the display unit 6 is switched to the image 62 based on the image data of the file name “007”. Here, since the drive unit 24 does not apply a voltage to the energization region 42, the energization region 44, and the energization region 46 (see FIG. 3), the drive unit 24 is displayed in the energization region 42 due to the memory property of the display unit 6. The image 56 being displayed, the image 58 being displayed in the energization area 44, and the image 60 being displayed in the energization area 46 are continuously displayed.

  Next, when one minute as the unit time has elapsed (current time 04:00, see FIG. 9), the CPU 20 switches the image displayed in the energization area 42 adjacent to the energization area 40 (see FIG. 3). Do. For example, the CPU 20 reads the image data with the file name “008” from the memory card 12 and writes it in an area corresponding to the energization area 42 in the VRAM 32.

  Next, the CPU 20 applies a predetermined voltage for displaying an image based on this image data to the energized region 42 of the display unit 6 by the driving unit 24, for example, as shown in the lower part of FIG. Then, the image 56 displayed in the energization region 42 of the display unit 6 is switched to the image 64 based on the image data of the file name “008”. Here, since the CPU 20 does not apply a voltage to the energization region 40, the energization region 44, and the energization region 46 (see FIG. 3), the CPU 62 displays the image 62 displayed in the energization region 40 and the energization region 44. The image 58 and the image 60 displayed in the energization region 46 are continuously displayed.

  Thereafter, when the battery 34 is charged and the value of the remaining amount of the battery 34 recovers to a predetermined value or more (see the diagram shown in the upper part of FIG. 10), the CPU 20 changes the display mode of the image display device 2 from the power saving display mode. Return to normal display mode.

  Next, when one minute, which is a unit time, has elapsed since the last time the image was displayed on the display unit 6 in the power saving display mode (current time 04:00, see FIG. 9) (current time 05:00, see FIG. 11). The CPU 20 reads the image data of the next image to be displayed from the memory card 12, for example, the image data of the file name “009”, and writes it in the VRAM 32.

  Next, the CPU 20 applies a predetermined voltage for displaying this image data to all the energized areas of the display unit 6 by the drive unit 24, for example, as shown in the lower part of FIG. The image 62, the image 64, the image 58, and the image 60 displayed on the display unit 6 are switched to the image 66 based on the image data of the file name “009”.

  According to the image display device 2 according to the first embodiment, when the remaining amount of the battery 34 is reduced, a voltage is applied to a part of the energization region of the display unit 6 and is displayed in the energization region. Therefore, in an image display device including a display unit having a memory property, power consumption can be reduced without giving the viewer a sense of incongruity.

  Next, processing of the image display device according to the second embodiment will be described. In the image display device according to the second embodiment, a plurality of energized areas (see FIG. 3) in the display unit 6 according to the first embodiment are used as a single energized area. Accordingly, in the second embodiment, portions different from those in the first embodiment will be described in detail, and descriptions of other overlapping portions will be omitted as appropriate.

  First, when the power is turned on, the CPU 20 starts detecting the remaining amount of the battery 34 via the power supply control unit 36, and when the value of the remaining amount of the battery 34 is equal to or greater than a predetermined value (FIG. 12). The CPU 20 sets the display mode of the image display device to the normal display mode. In the normal display mode, the unit time for displaying one image in the slide show display is 30 seconds.

  Here, when the slide show button 10 is pressed by the operator, the CPU 20 reads image data of an image to be initially displayed on the display unit 6 from the memory card 12, for example, image data of the file name “001”, and temporarily stores the RAM 30. Is stored in the VRAM 32.

  Next, the CPU 20 applies a predetermined voltage for displaying the image data to the display unit 6 by the drive unit 24, and, for example, as shown in the lower part of FIG. 12, the file name “001” is displayed. An image 50 based on the image data is displayed (current time 00:00).

  Next, when the unit time of 30 seconds elapses (current time 00:30, see FIG. 13), the CPU 20 reads the image data of the next image to be displayed from the memory card 12, for example, the image data of the file name “002”. Is written into the VRAM 32. Next, the CPU 20 applies a predetermined voltage for displaying the image data to the display unit 6 by the driving unit 24, and displays it on the display unit 6 as shown in the lower part of FIG. The displayed image 50 is switched to the image 52 based on the image data of the file name “002”.

  Here, when the remaining amount of the battery 34 is reduced and the remaining amount of the battery 34 is smaller than a predetermined value (shown in the upper part of FIG. 14), the CPU 20 normally sets the display mode of the image display device. The display mode is switched to the power saving display mode, and the time interval (that is, unit time) for switching images in the slide show display is changed from 30 seconds to 1 minute.

  In the power saving display mode, the CPU 20 displays the image even after 30 seconds, which is the unit time of the normal display mode, have elapsed since the last time the image was switched in the normal display mode (current time 00:30, see FIG. 13). This is the unit time of the power saving display mode from when the image was last switched in the normal display mode (current time 00:30, see FIG. 13) without switching (current time 01:00, see FIG. 15). When one minute has passed (current time 01:30, see FIG. 16), switching to the next image is performed. For example, as shown in the lower part of FIG. 16, the image 52 displayed on the display unit 6 is switched to the image 54 based on the image data of the file name “003”.

  Thereafter, when the battery 34 is charged and the value of the remaining amount of the battery 34 is restored to a predetermined value or more (shown in the upper part of FIG. 17), the CPU 20 normally displays the display mode of the image display device from the power saving display mode. When the mode is restored and 30 seconds, which is the unit time of the normal display mode, have passed since the last image switching in the power saving display mode (current time 01:30, see FIG. 16) (current time 02:00). 18), the image displayed on the display unit 6 is switched from the image 54 to the next image 56 as shown in the lower part of FIG. 18, for example.

  According to the image display device according to the second embodiment, when the remaining amount of the battery 34 is reduced, the display unit having the memory property is provided by changing the time interval for switching the images in the slide show display. In the image display apparatus, the power consumption can be reduced without giving the viewer a sense of incongruity.

  Next, processing of the image display device according to the third embodiment will be described. In the image display device according to the third embodiment, a plurality of energized regions (see FIG. 3) in the display unit 6 of the first embodiment are made into a single energized region. Accordingly, in the third embodiment, portions different from the first embodiment will be described in detail, and descriptions of other overlapping portions will be omitted as appropriate.

  First, when the value of the remaining amount of the battery 34 is equal to or greater than a predetermined value (see the diagram shown in the upper part of FIG. 19), when the slide show button 10 is pressed, the CPU 20 normally displays the display mode of the image display device. Set to mode. In the normal display mode, the unit time for displaying one image in the slide show display is 20 seconds.

  Here, when the slide show button 10 is pressed by the operator, the CPU 20 reads out, for example, image data of the file name “011” from the memory card 12 and stores it in the RAM 30.

  Next, based on the image data of the file name “011” stored in the RAM 30, the CPU 20 writes image data for displaying the image 70 (see the lower left diagram in FIG. 19) on the display unit 6 in the VRAM 32. . Next, the drive unit 24 applies a predetermined voltage to the display unit 6 to display the first image 70 based on the image data of the file name “011” (current time 0:00, see FIG. 19).

  Next, when the unit time of 20 seconds elapses (current time 00:20), the CPU 20 zooms and displays an image based on the image data of the file name “011” stored in the RAM 30. By performing the above, image data for displaying the image 72 (see the diagram in the lower part of FIG. 19) on the display unit 6 is generated. Next, the CPU 20 writes the generated image data into the VRAM 32 and switches the image 70 to the next image 72 based on the image data with the file name “011”.

  When the unit time of 20 seconds elapses (current time 00:40), the CPU 20 increases the zoom magnification and performs image processing based on the image data of the file name “011”, thereby generating an image 74 (FIG. 19). Image data for displaying on the display unit 6 is generated. Next, the CPU 20 writes the generated image data into the VRAM 32 and switches the image 72 to the last image 74 based on the image data with the file name “011”. As described above, in the third embodiment, processing for sequentially switching the images displayed on the display unit 6 by increasing the zoom magnification is performed.

  Here, when the value of the remaining amount of the battery 34 becomes smaller than a predetermined value as shown in the upper part of FIG. 20, the CPU 20 switches the display mode of the image display device from the normal display mode to the power saving display mode. The number of switching times and the switching time interval when switching the display from the previously displayed image to the currently displayed image are changed. For example, the number of images displayed on the display unit 6 is changed from three to two based on one image data, and the unit time for displaying one image on the display unit 6 is changed from 20 seconds to 30 seconds.

  When the power saving display mode is set, the CPU 20 has passed the current power saving display mode unit time of 30 seconds (current time) since the last image switching in the normal display mode (current time 00:40). 01:10, see FIG. 21), switching to the next image is performed. For example, the CPU 20 reads out the image data with the file name “012”, which is the next image data, from the memory card 12 and stores it in the RAM 30, and based on the image data with the file name “012”, the image 76 (lower part of FIG. 21). The image data to be displayed on the display unit 6 is written into the VRAM 32, and the first image 76 based on the image data with the file name “012” is displayed.

  Next, when 30 seconds as a unit time further elapses (current time 01:40), the CPU 20 zooms and displays an image based on the image data of the file name “012” stored in the RAM 30. By performing the processing, image data for displaying the image 78 (see the lower right diagram in FIG. 21) on the display unit 6 is generated. Next, the CPU 20 writes the generated image data into the VRAM 32 and switches the image 76 to the last image 78 based on the image data with the file name “012”. While the power saving display mode is maintained, the CPU 20 switches the image to the last image based on the same image data after 30 seconds from the display of the first image on the display unit 6, and further 30 seconds. When elapses, the process of switching to the first image based on the next image data is repeated.

  Thereafter, when the remaining amount of the battery 34 recovers to a predetermined value or more as shown in the upper part of FIG. 22, the CPU 20 returns the display mode to the normal display mode (see the lower part of FIG. 22). ). Then, when 20 seconds, which is the unit time of the normal display mode, have elapsed since the last image switching in the power saving display mode (current time 01:40) (current time 02:00, see FIG. 23), the CPU 20 Switches the image displayed on the display unit 6 to the next image. For example, the CPU 20 reads out the image data of the file name “013”, which is the next image data, from the memory card 12 and stores it in the RAM 30, and based on the image data of the file name “013”, the image 80 (the lower part of FIG. 23). The image data to be displayed on the display unit 6 is written into the VRAM 32, and the first image 80 based on the image data with the file name “013” is displayed.

  Next, when 20 seconds as the unit time of the normal display mode has elapsed (current time 02:20), the CPU 20 zooms in on the image based on the image data of the file name “013” stored in the RAM 30. By performing image processing to be displayed, image data for displaying the image 82 (see the diagram in the lower part of FIG. 23) on the display unit 6 is generated. Next, the CPU 20 writes the generated image data in the VRAM 32 and switches the image 80 to the image 82.

  When the unit time of 20 seconds elapses (current time 02:40), the CPU 20 increases the zoom magnification based on the image data of the file name “013” to perform image processing, thereby generating an image 84 (FIG. 23). Image data for displaying on the display unit 6 is generated. Next, the CPU 20 writes the generated image data in the VRAM 32 and switches the image 82 to the image 84.

  According to the image display device according to the third embodiment, when the remaining amount of the battery 34 is reduced, the number of switching and switching of images when switching the display from the previously displayed image to the currently displayed image. By changing the time interval, power consumption can be reduced in an image display device including a display unit having a memory property without causing an observer to feel uncomfortable.

  Next, processing of the image display device according to the fourth embodiment will be described. In the image display device according to the fourth embodiment, a plurality of energized regions (see FIG. 3) in the display unit 6 of the first embodiment are made into a single energized region. Therefore, in the fourth embodiment, portions different from the first embodiment will be described in detail, and descriptions of other overlapping portions will be omitted as appropriate.

  First, when the value of the remaining amount of the battery 34 is equal to or greater than a predetermined value (see the diagram shown in the upper part of FIG. 24), when the slide show button 10 is pressed, the CPU 20 normally displays the display mode of the image display device. Set to mode. In the normal display mode, the unit time for displaying one image in the slide show display is 20 seconds.

  Here, when the slide show button 10 is pressed by the operator, the CPU 20 reads out, for example, image data with the file name “020” and image data with the file name “021” from the memory card 12 and stores them in the RAM 30. .

  Next, the CPU 20 displays the image 90 (see the diagram on the left side of the lower part of FIG. 24) on the display unit 6 based on the image data with the file name “020” and the image data with the file name “021” stored in the RAM 30. The image data to be displayed is written in the VRAM 32. Next, the drive unit 24 applies a predetermined voltage to the display unit 6 to display the image data with the file name “020” and the first image 90 based on the image data with the file name “021” (currently Time 00:00, see FIG.

  Next, when the unit time of 20 seconds elapses (current time 00:20), the CPU 20 is based on the image data with the file name “020” and the image data with the file name “021” stored in the RAM 30. Then, image data for displaying the image 92 (see the lower part of FIG. 24) on the display unit 6 is written in the VRAM 32, and the image 90 is the image data with the file name “020” and the image with the file name “021”. Switch to the next image 92 based on the data.

  When the unit time of 20 seconds elapses (current time 00:40), the CPU 20 displays an image 94 (see the lower right diagram in FIG. 24) on the display unit 6 based on the image data of the file name “021”. The image data to be displayed is written into the VRAM 32, and the image 92 is switched to the image 94 based on the image data with the file name “021”. As described above, in the fourth embodiment, processing is performed in which the image displayed on the display unit 6 is switched stepwise from the side.

  Here, as shown in the upper part of FIG. 25, when the remaining amount of the battery 34 becomes smaller than a predetermined value, the CPU 20 switches the display mode of the image display device from the normal display mode to the power saving display mode. The number of switching times and the switching time interval when switching the display from the previously displayed image to the currently displayed image are changed. For example, the number of images displayed on the display unit 6 is changed from three to two based on one image data, and the unit time for displaying one image on the display unit 6 is changed from 20 seconds to 30 seconds.

  When the power saving display mode is set, the CPU 20 has passed the current power saving display mode unit time of 30 seconds (current time) since the last image switching in the normal display mode (current time 00:40). 01:10, see FIG. 26), switching to the next image is performed. For example, the CPU 20 reads out the image data of the file name “022” that is the next image data from the memory card 12 and stores the image data in the RAM 30, and stores the image data of the file name “021” and the image data of the file name “022”. Based on this, image data for displaying the image 96 (see the figure on the lower left side of FIG. 26) on the display unit 6 is written in the VRAM 32, and the image data with the file name “021” and the image data with the file name “022” are written. A based image 96 is displayed.

  Next, when 30 seconds as the unit time further elapses (current time 01:40), the CPU 20 determines the image 98 (lower part of FIG. 26) based on the image data of the file name “022” stored in the RAM 30. The image data to be displayed on the display unit 6 is written in the VRAM 32, and the image 96 is switched to the image 98 based on the image data with the file name “022”. When the power saving display mode is maintained, the CPU 20 turns the image 98 into image data with the file name “022” and the file name “023” when 30 seconds have elapsed since the image 98 was displayed on the display unit 6. When another 30 seconds elapses, the process of switching the image to the image based on the image data of the file name “023” is continued, and the same process is repeated thereafter.

  After that, as shown in the upper diagram of FIG. 27, when the value of the remaining amount of the battery 34 recovers to a predetermined value or more, the CPU 20 returns the display mode to the normal display mode (see the diagram shown in the lower diagram of FIG. 27). ). Then, when 20 seconds, which is the unit time of the normal display mode, have elapsed since the last image switching in the power saving display mode (current time 01:40) (current time 02:00, see FIG. 28), the CPU 20 Switches the image displayed on the display unit 6 to the next image. For example, the CPU 20 reads out the image data with the file name “023”, which is the next image data, from the memory card 12 and stores it in the RAM 30, and stores the image data with the file name “022” and the image data with the file name “023”. Based on this, image data for displaying the image 100 (see the diagram on the lower left side of FIG. 28) on the display unit 6 is written in the VRAM 32 and the image 100 is displayed.

  Next, when 20 seconds as the unit time in the normal display mode has elapsed (current time 02:20), the CPU 20 stores the image data of the file name “022” and the file name “023” stored in the RAM 30. Based on the image data, image data for displaying the image 102 (see the diagram in the lower part of FIG. 28) on the display unit 6 is written in the VRAM 32, and the image 100 is switched to the image 102.

  When the unit time of 20 seconds elapses (current time 02:40), the CPU 20 displays the image 104 (see the lower right diagram in FIG. 28) on the display unit 6 based on the image data of the file name “023”. The image data to be displayed is written in the VRAM 32, and the image 102 is switched to the image 104.

  According to the image display device according to the fourth embodiment, when the remaining amount of the battery 34 is reduced, the number of switching and the switching of images when switching the display from the previously displayed image to the currently displayed image. By changing the time interval, power consumption can be reduced in an image display device including a display unit having a memory property without causing an observer to feel uncomfortable.

  In each of the above-described embodiments, the display mode in the power saving display mode is different from the display mode in the normal display mode, so that the operator can be notified of a decrease in the remaining battery level.

  Further, in each of the above-described embodiments, since the value of the voltage applied to the display unit does not change even in the power saving display mode, the power consumption can be reduced without degrading the image quality.

  In the power saving display mode of the first embodiment, as shown on the lower left side of FIG. 8, the image 54 is in the energized region 40 (see FIG. 3), the image 56 is in the energized region 42, the image 58 is in the energized region 44, When each of the images 60 is displayed in the energized area 46 and the unit time has elapsed, the CPU 20 stores the image data of the image 62, the image data of the image 64, and the subsequent two image data, which are the next four image data, in the RAM 30. And overwritten in the VRAM 32, and a voltage is applied to the energized region 40 where the image 54 is displayed on the display unit 6 so that the image 54 is switched to the image 62 (shown on the lower right side of FIG. 8). reference). Here, since the CPU 20 does not apply a voltage to other energized regions, the images 56, 58, and 60 are continuously displayed due to the memory property of the display unit 6. Further, when the unit time has elapsed, the CPU 20 switches the image 56 to the image 64 by applying a voltage to the energized region 42 where the image 56 is displayed on the display unit 6 (shown on the lower right side of FIG. 9). reference). Thereafter, the remaining two images are switched in the same manner. When the unit time has elapsed since the switching of the four images is completed, the CPU 20 reads the next four image data from the RAM 30 and overwrites the VRAM 32, and sequentially switches the image in each energized region.

  In the above-described embodiment, the case where the display mode of the image display device is switched by determining whether or not the remaining amount of the battery 34 is equal to or greater than a predetermined value has been described as an example. The display mode may be switched by other methods. For example, it is assumed that the AC adapter is connected to the image display device in the power saving display mode, and the battery 34 is charged by the AC adapter. In this case, the CPU 20 may detect whether or not the battery 34 is charged from the AC adapter, and may switch to the normal display mode when charging is performed. Further, when the battery 34 is provided with a solar cell for charging, and the solar cell is sufficiently generating power, for example, in the power saving display mode, the supply amount of power per unit time from the solar cell to the battery 34 is the normal display mode. Switching to the normal display mode may be performed when the power per unit time required for switching the image is larger.

  In the above-described embodiment, a power saving display mode button for switching to the power saving display mode may be provided, and switching to the power saving display mode may be performed when the operator operates the power saving display mode button.

  In the first embodiment, the case where the energization region of the display unit 6 is divided into four locations has been described as an example. However, the number of energization regions is not limited to four as long as there are a plurality of energization regions.

  In the above-described embodiment, the case where the image displayed on the display unit 6 is read from the image data memory card 12 is described as an example. However, the wireless communication unit 38 receives the image data from the external device and receives the image data. An image based on the image data may be displayed on the display unit 6.

  DESCRIPTION OF SYMBOLS 2 ... Image display apparatus, 4 ... Apparatus main body, 6 ... Display part, 8 ... Power switch, 10 ... Slideshow button, 12 ... Memory card, 14 ... Memory card slot, 20 ... CPU, 22 ... Operation part, 24 ... Drive part 28 ... ROM, 30 ... RAM, 32 ... VRAM, 34 ... battery, 36 ... power supply control unit, 38 ... wireless communication unit

Claims (8)

A storage unit for storing image data;
A display unit having a memory function for displaying the image when a voltage for displaying an image based on the image data is applied, and maintaining the display of the image after the application of the voltage is completed;
A drive unit for driving the display unit;
An input unit for inputting an instruction to display the display unit with power saving,
When the instruction is input, the driving unit switches display contents in the partial area by applying the voltage to the partial area of the display unit. Image display device. A storage unit for storing image data;
A display unit having a memory function for displaying the image when a voltage for displaying an image based on the image data is applied, and maintaining the display of the image after the application of the voltage is completed;
A drive unit for driving the display unit;
An input unit for inputting an instruction to display the display unit with power saving,
The drive unit changes an image switching method displayed on the display unit when the instruction is input.   The image display device according to claim 2, wherein the driving unit changes an interval of the switching time of the image.   The image display apparatus according to claim 2, wherein the driving unit changes the number of times of switching the image. Battery,
A detection unit for detecting information about the battery,
The image display apparatus according to claim 1, wherein the input unit inputs the instruction based on a detection result in the detection unit. The detection unit detects the remaining amount of the battery,
The image display device according to claim 5, wherein the input unit inputs the instruction when the value of the remaining amount of the battery detected by the detection unit is smaller than a predetermined value. A power supply unit for supplying power to the battery;
The detection unit detects a power supply status from the power supply unit to the battery,
The image display device according to claim 5, wherein the input unit inputs the instruction based on the power supply status.   The image display apparatus according to claim 7, wherein the power feeding unit is an external power source or a solar battery.

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