Display-integrated tablet device providing coordinate detection

• US 5,552,568 A
• Filed: 08/31/1994
• Issued: 09/03/1996
• Est. Priority Date: 08/31/1993
• Status: Expired due to Fees

• Current Assignee: Futaba Denshi Kogyo KK
• Original Assignee: Futaba Denshi Kogyo KK
• Inventors: Nagasawa, Satoshi, Kobori, Yoichi, Hiraga, Katsuya, Onodaka, Koji
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): Shankar, Vijay
• Application Number:
  US08/297,540
• Time in Patent Office: 734 Days
• Field of Search: 178/18, 178/19, 178/20, 345/174, 345/179, 345/182, 345/156, 345/157, 345/183
• US Class Current: 178/18.03
• CPC Class Codes: G05G 9/047 the controlling member being movable by hand about orthogonal axes, e.g. joysticks for switches H01H25/04
• CPC Class Codes: G06F 3/0338 with detection of limited linear or angular displacement of an operating part of the device from a neutral position, e.g. isotonic or isometric joysticks
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0441 using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: H01H 2025/046 having a spherical bearing between operating member and housing or bezel
• CPC Class Codes: H01H 2025/048 having a separate central push, slide or tumbler button which is not integral with the operating part that surrounds it
• CPC Class Codes: H01H 2221/012 Joy stick type
• CPC Class Codes: H01H 2229/038 Folding of flexible printed circuit
• CPC Class Codes: H01H 25/04 Operating part movable angularly in more than one plane, e.g. joystick
• CPC Class Codes: H01H 25/041 having a generally flat operating member depressible at different locations to operate different controls
• CPC Class Codes: Y10T 74/20201 Control moves in two planes

Abstract

A display-integrated tablet device is disclosed and is capable of increasing an actual display period to improve luminance of an image displayed. An actual image display period in a one-image-plane display period is divided into a plurality of block display periods and a detection period is provided before or after each of the block display periods. During the detection period, a pulse for detection is generated from a stylus pen and a voltage obtained at each of electrodes is input to each of X- and Y-coordinate detection sections and held in those sections for coordinate detection. The device includes scan-side switch sections for respectively connecting X- and Y-scan drivers to X- and Y-electrodes, and detection-side switch sections for respectively connecting X- and Y-coordinate detection sections to the X- and Y-electrodes, so that the scan-side switches sections and detection-side switch sections are turned on and turned off during an actual display period, and turned off and turned on during a detection mode period, respectively.

Claims

1. A display device integrated tablet device comprising:

a tablet having a plurality of X-electrodes and Y-electrodes arranged in a matrix-like manner and including a display plane;

an X-electrode drive means for driving said X-electrodes at a predetermined timing;

a Y-electrode drive means for driving said Y-electrodes at a predetermined timing;

a coordinate input means for generating a coordinate location signal for detecting a tablet coordinate of said tablet;

an X-coordinate detection signal holding means, connected to said X-electrodes, and arranged for temporarily holding X-reception signals generated in said X-electrodes by said coordinate location signal;

a Y-coordinate detection signal holding means, connected to said Y-electrodes, and arranged for temporarily holding Y-reception signals generated in said Y-electrodes by said coordinate location signal;

a coordinate detection means, coupled to said X-coordinate detection signal holding means and said Y-coordinate detection signal holding means, to which said X-reception signals and X-electrode position data and said Y-reception signals and Y-electrode position data are input, for determining an X-coordinate and a Y-coordinate at which there is a maximal value of said X-reception signals and said Y-reception signals; and

a control means for controlling said X-electrode drive means and said Y-electrode drive means during an image display period, so as to permit an image display to be carried out on said display plane of said tablet and so as to permit said coordinate input means to generate said coordinate location signal during a coordinate detection period, resulting in said X-reception signals and said Y-reception signals being received and held by said X-coordinate detection signal holding means and said Y-coordinate detection signal holding means, respectively.

2. A display-integrated tablet device as defined in claim 1, wherein said display plane of said tablet is divided into two or more display regions, in correspondence to which block display periods are set;

and

a detection mode period is set before or after each of said block display periods.

3. A display-integrated tablet device as defined in claim 1 or 2, further comprising a switching means for connecting said X-electrodes and said Y-electrodes to said X-electrode drive means and said Y-electrode drive means, respectively, during said image display period, and for connecting said X-electrodes and said Y-electrodes to said X-coordinate detection signal holding means and said Y-coordinate detection signal holding means during said coordinate detection period, respectively.

4. A display-integrated tablet device according to claim 1, wherein said coordinate input means comprises a pen.

5. A device according to claim 4, wherein said coordinate input means comprises means for providing a voltage to said pen.