Touched Position Detection Method for Touch Panel

• US 20100060609A1
• Filed: 07/02/2009
• Published: 03/11/2010
• Est. Priority Date: 09/08/2008
• Status: Active Grant

• Current Assignee: Paneltouch Technologies LLC
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: KUMAGAI, Toshiyuki, ATSUTA, Toshiaki, HAYAKAWA, Koji, DOI, Koji, NAGATA, Koji, MAMBA, Norio
• Granted Patent: US 8,542,213 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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

In a touched position detection method for a touch panel for detecting a touched position, based on measured values by a plurality of sensors, presence of a touch is determined when a measured value by a sensor exceeds a touch threshold. As a touch threshold, a value which cannot be attained due to a mere noise but can due to presence of a touch is set. With respect to sensors located in the vicinity of a sensor showing a high measured value, a higher weighted value is applied to modify a measured value in a touched position calculation process than that to be applied to other sensors.

Claims

1. A touched position detection method for a touch panel for detecting a touched position, based on measured values by a plurality of sensors, comprising:

a step of selecting sensors located in a vicinity of a sensor showing a high measured value; and

a step of applying different noise reduction parameters to measured values by the sensors selected and measured values by other sensors.

2. The touched position detection method for a touch panel according to claim 1, wherein the noise reduction parameter is a predetermined to be subtracted from a measured value by a sensor to be referred to in a touched position calculation process.

3. The touched position detection method for a touch panel according to claim 1, wherein

the sensors are electrodes of which static capacitance is able to be measured, and

the measured values are values indicating static capacitance.

4. The touched position detection method for a touch panel according to claim 1, wherein the sensors selected are a set of sensors located within a predetermined distance from the sensor showing a high measured value.

5. A touched position detection method for a touch panel for detecting a touched position, based on a current measured value by a sensor and a reference value which is a measured value by a sensor with absence of a touch, wherein content of an update process for updating the reference value is controlled depending on presence or absence of a touch.

6. The touched position detection method for a touch panel according to claim 5, wherein

the sensor is an electrode of which static capacitance is able to be measured, and

the measured value is a value indicating static capacitance.

7. A touched position detection method for a touch panel for detecting a touched position, based on current measured values by sensors and reference values which are measured values by sensors with absence of a touch, comprising:

a step of selecting sensors located in a vicinity of a sensor showing a high measured value,

wherein

content of an update process for updating the reference values is controlled depending on whether or not sensors of concern are included in the sensors selected.

8. The touched position detection method for a touch panel according to claim 7, wherein

the sensors are electrodes of which static capacitance is able to be measured, and

the measured values are values indicating static capacitance.

9. The touched position detection method for a touch panel according to claim 7, wherein the sensors selected are a set of sensors located within a predetermined distance from the sensor showing a high measured value.