Position detecting device including display function

• US 8,780,056 B2
• Filed: 10/16/2009
• Issued: 07/15/2014
• Est. Priority Date: 10/31/2008
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Wacom Co Limited (Wacom)
• Inventors: Yamamoto, Sadao, Onoda, Naoto
• Primary Examiner(s): Beck, Alexander S
• Assistant Examiner(s): HERMANN, KIRK W
• Application Number:
  US12/581,069
• Publication Number:
  US 20100110029A1
• Time in Patent Office: 1,733 Days
• Field of Search: None
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0444 using a single conductive element covering the whole sensing surface, e.g. by sensing the electrical current flowing at the corners
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 3/3453 based on rotating particles or microelements

Abstract

A position detecting device includes: a display unit having a first electrode formed of a transparent conductive film, a plurality of second electrodes, and display material interposed between the first electrode and the second electrodes; a display driver configured to drive the display unit based on a video signal input to the display driver; and a position detecting section configured to detect a position of an indicator on the first electrode and to output the detected position. The display unit may comprise, for example, an “electronic paper,” such that the display state of the display unit can be maintained even after a drive power applied between the first electrode and the second electrodes is discontinued.

Claims

1. A position detecting device comprising:

a display unit which has a first electrode, one or more second electrodes, and display material interposed between the first electrode and the one or more second electrodes, the display unit being configured such that the display material maintains a display state after a drive power applied between the first electrode and the one or more second electrodes is discontinued;

a display driver configured to drive the display unit in response to an input signal;

a position detecting section configured to detect a position indicated on the first electrode by an indicator, wherein the first electrode is commonly used by the position detecting section to detect an indicated position and by the display unit to generate a display; and

a control section configured to control drive time of the display driver and the position detecting section time-divisionally based on a determined presence of the input signal to the display driver and based on a determined presence of the indicator on or adjacent to the first electrode such that at a first state, in which the input signal is not present and the display driver is not driven while the indicator is present and the position detecting section is continuously driven to detect an indicated position of the indicator, in case a display update signal is received, the control section transitions from the first state to a second state, in which the display driver is time-divisionally driven in between the drive time of the position detecting section,

wherein the control section is further configured such that at a third state, in which the input signal is present and the display driver is time-divisionally driven in between the drive time of the position detecting section while the indicator is not present, in case the indicator is determined to be present, the control section transitions from the third state to the second state,

wherein, in the second state, more drive time is assigned to drive the position detecting section than the drive time assigned to drive the position detecting section in the third state.

2. The position detecting device according to claim 1, wherein the position detecting section is an electrostatic capacitive coupling type position detecting section.

3. The position detecting device according to claim 1, wherein the first electrode is an electrode film including a plurality of electrodes arranged in a matrix.

4. The position detecting device according to claim 2, wherein the indicator is at least one of a human finger and an electrostatic coupling type position indicator, and the position detecting device is configured to detect a position where the indicator and the first electrode are electrostatically coupled with each other.

5. The position detecting device according to claim 1, wherein the position detecting section is a resistance film type position detecting section.

6. The position detecting device according to claim 1, wherein the first electrode includes a plurality of sensors arranged in a matrix, and the position detecting section is an electromagnetic induction type position detecting section.

7. The position detecting device according to claim 6, wherein the indicator is an electromagnetic induction type position indicator having a resonant circuit configured by a coil and a capacitor.

8. The position detecting device according to claim 1, wherein the control section is configured to preferentially drive the position detecting section to detect an indicated position than driving the display driver.

9. The position detecting device according to claim 1, wherein the control section controls drive time of the display driver and the position detecting section time-divisionally based on a display update signal received from the display driver.

10. The position detecting device according to claim 1, wherein the control section controls drive time of the display driver and the position detecting section time-divisionally based on a signal received from the position detecting section indicating that detection of an indicated position is completed.

11. The position detecting device according to claim 1, wherein the control section controls drive time of the display driver and the position detecting section time-divisionally based on a signal received from the position detecting section indicating the determined presence of the indicator on or adjacent to the first electrode.