Object detection for a capacitive ITO touchpad

• US 20090114457A1
• Filed: 12/06/2007
• Published: 05/07/2009
• Est. Priority Date: 11/01/2007
• Status: Abandoned Application

• Current Assignee: Elan Microelectronics Corporation
• Original Assignee: Elan Microelectronics Corporation
• Inventors: Lii, Jia-Yih
• Application Number:
  US11/987,922
• Publication Number:
  US 20090114457A1
• Time in Patent Office: Days
• US Class Current: 178/18.60
• 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 the detection of multiple objects touching on a capacitive ITO touchpad, the relative levels of the capacitive measurements received by a touch integrated circuit are used to determine the relative position between the multiple objects.

Claims

1. An object detection for a capacitive ITO touch pad, comprising the steps of:

detecting magnitude of a plurality of capacitive measurements generated when a plurality of objects touch the touch pad; and

determining relative locations of the plurality of objects according to the magnitude of the plurality of capacitive measurements.

2. An object detection for a capacitive ITO touch pad, comprising the steps of:

detecting magnitude of a plurality of capacitive measurements in a first and a second directions generated when a plurality of objects touch the touch pad;

determining relative locations of the plurality of objects in the second direction according to the magnitude of the plurality of capacitive measurements in the first direction; and

determining relative locations of the plurality of objects in the first direction according to the magnitude of the plurality of capacitive measurements in the second direction.

3. An object detection for a capacitive ITO touch pad, comprising the steps of:

generating a plurality of capacitive measurements in a first direction and a second direction when a plurality of objects touching the touch pad;

determining relative locations of the plurality of objects in the first direction according to relative locations of the plurality of capacitive measurements in the first direction; and

determining relative locations of the plurality of objects in the second direction according to the magnitude of the plurality of capacitive measurements in the second direction.

4. A capacitive ITO touch pad, comprising

a sensor having a plurality of ITO sensing lines for generating a plurality of capacitive measurements when a plurality of objects touch;

and

a touch IC connecting the sensor for detecting the capacitive measurements from the sensor;

wherein, magnitude of the plurality of capacitive measurements is used to determine relative locations of the plurality of objects.

5. The capacitive ITO touch pad as claimed in claim 4, wherein the plurality of ITO sensing lines are disposed in one direction.

6. The capacitive ITO touch pad as claimed in claim 4, wherein the plurality of ITO sensing lines are disposed in a first and a second directions.

7. The capacitive ITO touch pad as claimed in claim 6, wherein the first and the second directions are mutually perpendicular.

8. The capacitive ITO touch pad as claimed in claim 6, wherein magnitude of the plurality of capacitive measurements in the first direction is used to determine the relative positions of the plurality of objects in the second direction.

9. The capacitive ITO touch pad as claimed in claim 8, wherein magnitude of the plurality of capacitive measurements in the second direction is used to determine the relative positions of the plurality of objects in the first direction.

10. The capacitive ITO touch pad as claimed in claim 8, wherein relative positions of the plurality of capacitive measurements in the first direction is used to determine the relative positions of the plurality of objects in the first direction.