TOUCH PANEL DEVICE

• US 20090183931A1
• Filed: 07/01/2008
• Published: 07/23/2009
• Est. Priority Date: 01/21/2008
• Status: Abandoned Application

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: OKANO, Yuichi, Kawamata, Takenori
• Application Number:
  US12/165,947
• Publication Number:
  US 20090183931A1
• Time in Patent Office: Days
• US Class Current: 178/18.30
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• 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

Abstract

A touch panel unit includes a plurality of electrodes arranged in directions of an X axis and a Y axis. A screening electrode switching control circuit handles each of electrodes arranged in the direction of the X axis as a detecting electrode and handles electrodes arranged in the direction of the Y axis as screening electrodes when an arithmetic unit detects the location of an approach or a touch to or with the touch panel unit in the direction of the X axis, whereas the screening electrode switching control circuit handles the electrodes arranged in the direction of the X axis as the screening electrodes and handles each of the electrodes arranged in the direction of the Y axis as the detecting electrode when the arithmetic unit detects the location of the approach or the touch to or with the touch panel unit in the direction of the Y axis.

Claims

1. A touch panel device comprising:

a touch panel unit in which a plurality of electrodes are arranged;

an arithmetic circuit for detecting a change in capacitance of one of the electrodes resulting from an approach or a touch of an input means to or with said touch panel unit, and detects a location of said approach or said touch;

a screening electrode switching control circuit for establishing an electrode connection in such a way that a part of said plurality of electrodes serves as detecting electrodes, and a remaining part of said plurality of electrodes serves as screening electrodes and has a same potential as that of said detecting electrodes.

2. The touch panel device according to claim 1, wherein said touch panel unit is of matrix type in which said plurality of electrodes include electrodes arranged in a direction of an X axis and electrodes arranged in a direction of a Y axis.

3. The touch panel device according to claim 2, wherein said screening electrode switching control circuit handles each of the electrodes arranged in the direction of the X axis as the detecting electrode and handles the electrodes arranged in the direction of the Y axis as the screening electrodes when detecting the location of said approach or said touch to or with said touch panel unit in the direction of the X axis, whereas said screening electrode switching control circuit handles the electrodes arranged in the direction of the X axis as the screening electrodes and handles each of the electrodes arranged in the direction of the Y axis as the detecting electrode when detecting the location of said approach or said touch to or with said touch panel unit in the direction of the Y axis.

4. The touch panel device according to claim 3, wherein the plurality of electrodes arranged in said touch panel unit are arranged in such a way that an area in which each of the electrodes arranged in the direction of the X axis and each of the electrodes arranged in the direction of the Y axis overlap each other becomes small.

5. The touch panel device according to claim 1, wherein said touch panel device has a correction circuit for correcting an amount of change in capacitance of a detecting electrode on a basis of the electrode connection established by said screening electrode switching control circuit, and said arithmetic circuit detects the location of the approach or the touch on a basis of the amount of change corrected by said correction circuit.

6. The touch panel device according to claim 2, wherein said touch panel device has a correction circuit for correcting an amount of change in capacitance of a detecting electrode on a basis of the electrode connection established by said screening electrode switching control circuit, and said arithmetic circuit detects the location of the approach or the touch on a basis of the amount of change corrected by said correction circuit.

7. The touch panel device according to claim 3, wherein said touch panel device has a correction circuit for correcting an amount of change in capacitance of a detecting electrode on a basis of the electrode connection established by said screening electrode switching control circuit, and said arithmetic circuit detects the location of the approach or the touch on a basis of the amount of change corrected by said correction circuit.

8. The touch panel device according to claim 4, wherein said touch panel device has a correction circuit for correcting an amount of change in capacitance of a detecting electrode on a basis of the electrode connection established by said screening electrode switching control circuit, and said arithmetic circuit detects the location of the approach or the touch on a basis of the amount of change corrected by said correction circuit.