Display device

• US 7,545,398 B2
• Filed: 11/11/2004
• Issued: 06/09/2009
• Est. Priority Date: 11/28/2003
• Status: Expired due to Fees

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Sawada, Munenori
• Primary Examiner(s): Lefkowitz; Sumati
• Assistant Examiner(s): SITTA, GRANT
• Application Number:
  US10/985,643
• Publication Number:
  US 20050184975A1
• Time in Patent Office: 1,671 Days
• Field of Search: 345/204, 345/901, 345/85, 345/107, 434/317
• US Class Current: 345/211
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06Q 30/0277 Online advertisement
• CPC Class Codes: G09G 2330/02 Details of power systems and of start or stop of display operation
• CPC Class Codes: G09G 3/3629 using liquid crystals having memory effects, e.g. ferroelectric liquid crystals
• CPC Class Codes: Y10S 345/901 Electronic book with display

Abstract

There is provided a battery-driven electronic book reader for switchingly displaying each page of contents separated in predetermined pages on a cholesteric liquid crystal panel, wherein a remaining available battery level is detected (step S102), the number of pages to be switchedly displayed on the cholesteric liquid crystal panel is calculated based on the detected remaining available battery level (step S104), and the calculated number of pages is displayed on the cholesteric liquid crystal panel (step 105).

Claims

1. A display device driven with a remaining battery level, for switchingly displaying each page of contents to be displayed on a storage-type display unit capable of holding contents which have been displayed thereon even if a power supply thereto is stopped, the display device comprising:

a remaining battery level detection section for detecting a remaining battery level; and

a notification section for notifying a correspondence relation between the detected remaining battery level and a number of displayable pages of the contents,

wherein the notification section calculates power consumption required for switchingly displaying remaining pages of contents displayed on the storage-type display unit and makes the notification based only on the caculated power consumption required for switchingly displaying the remaining pages of content and the remaining battery level detected by the remaining battery level detection section by;

sequentially generating raster data of contents of the page next to the contents displayed on the display device,

causing the raster data to be sequentially stored, and

referring to a data table in which values of power consumption for one page are set according to temperatures of a cholesteric liquid crystal panel and driving method.

2. The display device according to claim 1, wherein the notification section notifies a user of the correspondence relation when the user selects contents to be displayed on the storage-type display unit.

3. The display device according to claim 1, wherein, when a value obtained by subtracting the calculated power consumption from the remaining battery level detected by the remaining battery level detection section is a predetermined threshold or below, the notification section makes a notification to that effect.

4. The display device according to claim 1, comprising a display operation limiting section for enabling switching display from a page displayed on the storage-type display unit only to the next page when the value obtained by subtracting the calculated power consumption from the remaining battery level detected by the remaining battery level detection section is a predetermined threshold or below.

5. The display device according to claim 3, comprising a display operation limiting section for enabling switching display from a page displayed on the storage-type display unit only to the next page when the value obtained by subtracting the calculated power consumption from the remaining battery level detected by the remaining battery level detection section is a predetermined threshold or below.

6. The display device according to claim 1, wherein the notification section calculates a maximum number of pages to be switchedly displayed on the storage-type display unit, based on the remaining battery level detected by the remaining battery level detection section and makes the notification based on the maximum calculated number of pages.

7. The display device according to claim 6, wherein, when the calculated number of pages is a reference number of pages or larger, the notification section makes a notification that a certain reference number had been calculated.

8. The display device according to claim 7, wherein it is possible to set multiple values of the reference number of pages.

9. The display device according to claim 8, wherein, when the calculated number of pages is smaller than a smallest reference number of pages among the multiple values of the reference number of pages, the notification section immediately notifies the calculated number of pages.

10. The display device according to claim 6, comprising a power consumption calculation section for calculating power consumed by the switching display, based on change in the remaining battery level detected by the remaining battery level detection section, wherein the notification section calculates the number of pages to be switchedly displayed on the storage-type display unit, based on the remaining battery level detected by the remaining battery level detection section and the calculated power consumption calculated by the power consumption calculation section.

13. The display device according to claim 1, comprising a battery for a particular circuit for supplying power to a particular circuit the power consumption of which changes with operation time and a battery used for the switching display, wherein the remaining battery level detection section detects a remaining level of the battery used for the switching display.

14. The display device according to claim 1, wherein a non-volatile memory is used as a memory for storage of data generated by a control process of the display device.

15. The display device according to claim 1, comprising a CPU for executing a display operation limiting process, wherein a data table is referenced, the power consumption for one page is calculated based on the temperature, the number of remaining pages of the displayed contents is multiplied by the power consumption required for rewriting one page, a multiplication result is determined as the power consumption required for displayed remaining pages, if a subtraction result obtained by subtracting the power consumption required for displaying remaining pages from the remaining available driving battery level is a predetermined threshold or below, an inhibiting signal is outputted to an I/O, the I/O determines whether an inhibiting signal is outputted from the CPU, and if the inhibiting signal is not outputted, the I/O outputs a page backward signal to the CPU in response to the page backward button being pressed, and outputs a sequentially forward signal to the CPU in response to the sequentially forward button being pressed, and if the inhibiting signal is outputted, output of a page backward signal and output of a sequentially forward signal are inhibited.

16. The display device according to claim 1, wherein the data table is correctable based on the calculated power consumption required for switchingly displaying the remaining pages of content which is at least one of:

newly calculated power consumption for one page;

a mean value between the power consumption for one page which has been stored in the data table; and

newly calculated power consumption for one page

and the calculated power consumption required for switchingly displaying the remaining pages of content may be calculated by adding a weight larger than the newly calculated power consumption for one page to the power consumption for one page which has been stored in the data table.

11. A display device driven with a remaining battery level, for switchingly displaying each page of contents to be displayed on a storage-type display unit, the display device comprising:

a remaining battery level detection section for detecting a remaining battery level; and

a notification section for notifying a correspondence relation between the detected remaining battery level and number of displayable pages of the contents,

wherein the notification section calculates the number of pages to be switchedly displayed on the storage-type display unit based only on the remaining battery level detected by the remaining battery level detection section and a data table showing the relation between power consumption and a method of driving the storage-type display unit by;

sequentially generating raster data of contents of the page next to the contents displayed on the display device,

causing the raster data to be sequentially stored, and

referring to the data table in which values of power consumption for one page are set according to temperatures of a cholesteric liquid crystal panel and driving method.

12. A display device driven with a remaining battery level, for switchingly displaying each page of contents to be displayed on a storage-type display unit, the display device comprising:

a remaining battery level detection section for detecting a remaining battery level;

a notification section for notifying a correspondence relation between the detected remaining battery level and number of displayable pages of the contents; and

a temperature detection section for detecting temperature of the storage-type display unit,

wherein the notification section calculates the number of pages to be switchedly displayed on the storage-type display unit based only on the remaining battery level detected by the remaining battery level detection section and the temperature detected by the temperature detection section by;

sequentially generating raster data of contents of the page next to the contents displayed on the display device,

causing the raster data to be sequentially stored, and

referring to a data table in which values of power consumption for one page are set according to temperatures of a cholesteric liquid crystal panel and driving method.