Tablet integrated with display

• US 5,528,267 A
• Filed: 06/24/1994
• Issued: 06/18/1996
• Est. Priority Date: 12/19/1988
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ise, Masahiro
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Liang, Regina
• Application Number:
  US08/265,015
• Time in Patent Office: 725 Days
• Field of Search: 345/174, 345/175, 345/179, 345/180, 345/181, 345/182, 345/183, 345/104, 341/33, 341/5, 178/18, 178/19, 178/20
• US Class Current: 345/174
• 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

Abstract

A tablet integrated with a display comprising a matrix panel having row and column electrodes, a detecting conductor, a row electrode driver, a column electrode driver, a row coordinate detecting circuit and a column coordinate detecting circuit, in case of display mode, the row electrode driver applying the row scanning pulse successively to every row electrode of the matrix panel from one to another, and the column electrode driver applying voltage in accordance with the display data simultaneously to the column electrode of the matrix panel each time the row scanning pulse is applied successively to the row electrode of the matrix panel, in case of row detection mode, the row electrode driver applying the row scanning pulse successively to the row electrode of the matrix panel, and receiving the row scanning pulse detected through electrostatic capacitive coupling caused by the detecting conductor touching an arbitrary position on the matrix panel, so as to present the row coordinate of the position which the detecting conductor touches, and in case of column detection mode, the column electrode driver applying the column scanning pulse successively to the column electrode of the matrix panel, and the column coordinate detecting circuit receiving the column scanning pulse detected through electrostatic capacitive coupling caused by the detecting conductor touching an arbitrary position on the matrix panel, so as to present the column coordinate of the position which the detecting conductor touches.

Claims

1. A tablet integrated with a display comprising:

a matrix for display, having row and column electrodes;

a detecting conductor which can be coupled capacitively with said row and column electrodes when touched on said matrix panel;

a row electrode driver for applying a row scanning pulse successively to every row electrode of said matrix panel;

a column electrode driver for applying a column scanning pulse successively to every column electrode of said matrix panel and applying a voltage corresponding to display data for a predetermined amount of time;

a timing generator for transferring said display data to said column electrode driver and applying timing signals for determining timings of said row and column scanning pulses to said row electrode driver and said column electrode driver;

a row coordinate detecting circuit electrically connected to said detecting conductor, for detecting a row coordinate; and

a column coordinate detecting circuit electrically connected to said detecting conductor, for detecting a column coordinate;

wherein

during a display mode, said row electrode driver applies said row scanning pulse successively to every row electrode of said matrix panel from one to another, and said column electrode driver applies a voltage, in accordance with said display data, simultaneously to said column electrode of said matrix panel each time said row scanning pulse is applied successively to said row electrode of said matrix panel;

during a row detection mode, said row electrode driver applies said row scanning pulse successively to said row electrode of said matrix panel, and said row coordinate detecting circuit receives said row scanning pulse detected by said detecting conductor; and

during a column detection mode, said column electrode driver applies said column scanning pulse successively to said column electrode of said matrix panel, and said column coordinate detecting circuit receives said column scanning pulse detected by said detecting conductor;

said tablet integrated with a display further comprising means for effecting said display mode concurrently with said row detection mode to perform said row detection mode and column detection mode during alternate periods of time in a time sharing manner, means for comparing a signal outputted from said detecting conductor with a reference voltage during said row detection mode and means for omitting said column detection mode to effect said subsequent row detection mode when said signal outputted from said detecting conductor is below said reference voltage.

2. A tablet according to claim 1, wherein, in said row scanning mode, said row scanning pulse having a pulse width sufficient that said row scanning pulse is concurrently applied to plurality of adjacent row electrodes.

3. A tablet according to claim 1, wherein, in said column scanning mode, said column scanning pulse having a pulse width sufficient that said column scanning pulse is concurrently applied to a plurality of adjacent column electrodes.

4. A tablet integrated with a display comprising:

a matrix for display, having row and column electrodes;

a detecting conductor which can be coupled capacitively with said row and column electrodes when touched on said matrix panel;

a row electrode driver for applying a row scanning pulse successively to every row electrode of said matrix panel;

a column electrode driver for applying a column scanning pulse successively to every column electrode to said matrix panel and a voltage corresponding to display data for a predetermined amount of time;

a timing generator for transferring said display data to said column electrode driver and applying timing signals for determining timings of said row and column scanning pulses to said row electrode driver and said column electrode driver;

a row coordinate detecting circuit electrically connected to said detecting conductor, for detecting a row coordinate, and

a column coordinate detecting circuit electrically connected to said detecting conductor, for detecting a column coordinate;

wherein,

during a display mode, said row electrode driver applies said row scanning pulse successively to every row electrode of said matrix panel from one to another, and said column electrode driver applies a voltage, in accordance with said display data, simultaneously to said column electrode of said matrix panel each time said row scanning pulse is applied successively to said row electrode of said matrix panel;

during a row detection mode, said row electrode driver applies said row scanning pulse successively to said row electrode of said matrix panel, and said row coordinate detecting circuit receives said row scanning pulse detected through electrostatic capacitive coupling caused by said detecting conductor touching an arbitrary position on said matrix panel; and

during a column detection mode, said column electrode driver applies said column scanning pulse successively to said column electrode of said matrix panel, and said column coordinate detecting circuit receives said column scanning pulse detected through electrostatic capacitive coupling caused by said detecting conductor touching an arbitrary position on said matrix panel;

said tablet integrated with a display further comprising;

means for effecting said display mode concurrently with said row detection mode to perform said row detection mode and column detection mode during alternate periods of time in a time sharing manner and

means for omitting said column detection mode to effect a subsequent row detection mode when said detecting conductor is untouched on said matrix panel and said row coordinate detecting circuit does not receive said row scanning pulse through said detecting conductor during said row detection mode.

5. A tablet according to claim 4, wherein, in said row scanning mode, said row scanning pulse having a pulse width sufficient that said row scanning pulse is concurrently applied to a plurality of adjacent row electrodes.

6. A tablet according to claim 4, wherein, in said column scanning mode, said column scanning pulse having a pulse width sufficient that said column scanning pulse is concurrently applied to a plurality of adjacent column electrodes.