METHOD OF DETERMINING CONTACT POSITION IN ELECTRONIC APPARATUS

• US 20090284270A1
• Filed: 04/23/2009
• Published: 11/19/2009
• Est. Priority Date: 05/16/2008
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: OTA, Hitoshi
• Granted Patent: US 8,310,247 B2
• Time in Patent Office: Days
• US Class Current: 324/661
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• 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

There is provided a method of determining a contact position in an electronic apparatus including a plurality of capacitance sensing circuits that measures changes in capacitance and outputs capacitance measuring signals and a plurality of light sensing circuits that measures light intensities of incident light and outputs light measuring signals. The method includes acquiring the capacitance measuring signals by sequentially scanning the plurality of capacitance sensing circuits, determining whether a target object is in contact with a contact surface based on the acquired capacitance measuring signals, acquiring the light measuring signals by sequentially scanning the plurality of light sensing circuits after the target object is determined to be in contact with the contact surface in the determining of whether the target object is in contact with the contact surface, and determining a position of the contact surface, with which the target object is in contact, based on the acquired light measuring signals. The acquiring of the capacitance measuring signals and the determining of whether the target object is in contact with the contact surface are repeated until the target object is determined to be in contact with the contact surface in the determining of whether the target object is in contact with the contact surface.

Claims

1. A method of determining a contact position in an electronic apparatus including a plurality of capacitance sensing circuits that measures changes in capacitance and outputs capacitance measuring signals and a plurality of light sensing circuits that measures light intensities of incident light and outputs light measuring signals, the method comprising:

acquiring the capacitance measuring signals by sequentially scanning the plurality of capacitance sensing circuits;

determining whether a target object is in contact with a contact surface based on the acquired capacitance measuring signals;

acquiring the light measuring signals by sequentially scanning the plurality of light sensing circuits after the target object is determined to be in contact with the contact surface in the determining of whether the target object is in contact with the contact surface; and

determining a position of the contact surface, with which the target object is in contact, based on the acquired light measuring signals,

wherein the acquiring of the capacitance measuring signals and the determining of whether the target object is in contact with the contact surface are repeated until the target object is determined to be in contact with the contact surface in the determining of whether the target object is in contact with the contact surface.

2. The method according to claim 1, wherein the process returns to the acquiring of the capacitance measuring signals when the determining of the position of the contact surface is completed.

3. The method according to claim 1, further comprising determining whether the target object is distantly positioned from the contact surface based on the acquired light measuring signals between the acquiring of the light measuring signals and the determining of the position of the contact surface,

wherein, when the target object is determined to be distantly positioned from the contact surface in the determining of whether the target object is distantly positioned, the process proceeds to the acquiring of the capacitance measuring signals,

wherein, when the target object is determined to be in contact with the contact surface in the determining of whether the target object is distantly positioned, the process proceeds to the determining of the position of the contact surface, and

wherein, when the determining of the position of the contact surface is completed, the process returns to the acquiring of the light measuring signals.

4. The method according to claim 3, wherein, the determining of whether the target object is distantly positioned from the contact surface is comparing the light measuring signals with a reference level and determining whether the target object is distantly positioned from the contact surface based on the result of comparison.