Display apparatus and data transfer apparatus for display device

• US 6,043,798 A
• Filed: 06/26/1997
• Issued: 03/28/2000
• Est. Priority Date: 06/26/1996
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Mizutome, Atsushi, Yamamoto, Takashi
• Primary Examiner(s): Hjerpe, Richard A.
• Assistant Examiner(s): Laneau, Ronald
• Application Number:
  US08/883,454
• Time in Patent Office: 1,006 Days
• Field of Search: 345/1, 345/3, 345/103, 345/87, 345/88
• US Class Current: 345/1.1
• CPC Class Codes: G06F 3/1431 using a single graphics controller
• CPC Class Codes: G06F 3/147 using display panels
• CPC Class Codes: G09G 2310/04 Partial updating of the display screen
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2370/04 Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
• CPC Class Codes: G09G 3/3629 using liquid crystals having memory effects, e.g. ferroelectric liquid crystals
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04

Abstract

A display apparatus includes a common data generator unit for generating picture data, a plurality of display units each comprising a display device for displaying pictures based on the picture data, and a picture data transfer line connecting the common data generator unit with the plurality of display units. The plurality of display units include a first display unit comprising a memory characteristic display device and a second display unit comprising a non-memory characteristic display device, which are driven so that data transfer to the first display unit comprising a memory characteristic display device is performed in a blanking period when picture data transfer to the second display unit comprising a non-memory characteristic display device is not performed. As a result, a plurality of display units having different display characteristics, e.g., those including a memory characteristic chiral smectic liquid crystal device and a non-memory characteristic TFT-matrix liquid crystal device, can be driven to simultaneously display mutually closely rotated pictures based on picture data supplied in a time-sharing manner from a common data generator unit.

Claims

1. A display apparatus, comprising:

a common data generator unit for generating picture data, a plurality of display units each comprising a display device for displaying pictures based on the picture data, and a picture data transfer line connecting the common data generator unit with the plurality of display units, wherein

said plurality of display units include a first display unit comprising a memory characteristic display device and a second display unit comprising a non-memory characteristic display device, which are driven so that picture data transfer from the common data generator unit to the first display unit comprising a memory characteristic display device through the picture data transfer line is performed in a blanking period when picture data transfer from the common data generator unit to the second display unit comprising a non-memory characteristic display device through the picture data transfer line is not performed,

wherein said picture data includes data for designating one of said plurality of display units connected by the picture data transfer line, data for designating one of scanning lines of the designated display unit and display data for determining display states at pixels on the designated scanning line.

2. A display apparatus according to claim 1, wherein said plurality of display units are connected in series to the picture data transfer line.

3. A display apparatus according to claim 1, wherein said first display unit comprising a memory characteristic display device further includes a memory means for storing picture data for a plurality of scanning lines, said memory means having a capacity sufficient to store a maximum quantity of picture data transferable within the blanking period.

4. A display apparatus according to claim 1, wherein said memory characteristic display device is a display device using a ferroelectric liquid crystal.

5. A display apparatus according to any one of claims 1 to 4, wherein said picture data transfer line comprises a data signal line for passing picture data and a data demand signal from the display units, a discrimination signal line for passing a signal for discriminating whether data passing through said data signal line and a judgment signal line for judging whether the picture data sent to the data signal line is data for designating one of the display units or data for designating one of scanning lines.

7. A display apparatus according to claim 1 or 6, wherein one cycle period for outputting picture data to the second display unit is longer than one cycle period for outputting picture data to the first display unit.

8. A display apparatus according to claim 1 or 6, wherein picture data for one frame is outputted to one cycle period for the second display unit, and picture data less than one frame data is outputted to one cycle period for the first display unit.

9. A display apparatus according to claim 1 or 6, wherein said memory characteristic display device comprises a device using a chiral smectic liquid crystal.

10. A display apparatus according to claim 1 or 6, wherein said non-memory characteristic display device comprises an active matrix liquid crystal device, a plasma device or an electron discharge device.

11. A display apparatus according to claim 1, wherein said picture data includes data for designating one of said plurality of display units connected by a picture data transfer line.

6. A display apparatus, comprising:

a common data generator unit for generating picture data, a first display unit comprising a memory characteristic display device, a second display unit comprising a non-memory characteristic display device, and a data transfer apparatus for transferring picture data for picture display from the common data generator unit to the first and second display units through a common output line,

wherein said data transfer apparatus includes control means for outputting picture data from the common data generator unit to the second display unit through the common output line within each of successive prescribed cycle periods between which a blanking period is placed, and for outputting picture data from the common data generator unit to the first display unit through the common output line in the blanking period,

wherein said picture data includes data for designating one of said first and second display units connected by the common output line, data for designating one of scanning lines of the designated display unit and display data for determining display states at pixels on the designated scanning line.

12. A display apparatus according to claim 6, wherein said picture data includes data for designating one of the first and second display units connected by a picture data transfer line.

13. A data transfer apparatus for transferring picture data for picture display to a first display unit comprising a memory characteristic display device and a second display unit comprising a non-memory characteristic display device via a common output line,

wherein said data transfer apparatus includes control means for outputting picture data to the second display unit within each of successive prescribed cycle periods between which a blanking period is placed, and for outputting picture data to the first display unit in the blanking period.

14. A data transfer apparatus according to 13, wherein one cycle period for outputting picture data to the second display unit is longer than one cycle period for outputting picture data to the first display unit.

15. A data transfer apparatus according to claim 13, wherein picture data for one frame is outputted to one cycle period for the second display unit, and picture data less than one frame data is outputted to one cycle period for the first display unit.

16. A data transfer apparatus according to claim 13, wherein said picture data includes data for designating one of said plurality of display units connected by a picture data transfer line.