Resistive force sensor with capacitive discrimination

• US 20090020343A1
• Filed: 08/06/2007
• Published: 01/22/2009
• Est. Priority Date: 07/17/2007
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Zadesky, Stephen, Rothkopf, Fletcher R.
• Application Number:
  US11/882,881
• Publication Number:
  US 20090020343A1
• Time in Patent Office: Days
• US Class Current: 178/18.50
• CPC Class Codes: G06F 2203/0382 Plural input, i.e. interface arrangements in which a plurality of input device of the same type are in communication with a PC
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/9625 using a force resistance transducer
• CPC Class Codes: H03K 2217/94026 Automatic threshold calibration; e.g. threshold automatically adapts to ambient conditions or follows variation of input
• CPC Class Codes: H03K 2217/96031 Combination of touch switch and LC display
• CPC Class Codes: H03K 2217/96054 Double function: touch detection combined with detection of a movable element

Abstract

A resistive force sensor with capacitive discrimination is disclosed. According to an example of the disclosure, a sensor is directed to detect resistance and capacitance in an alternating fashion, the resistance indicating a force being applied to an input area of a device, and the capacitance indicating a proximity of a body part to the input area of the device, and the detected resistance and capacitance are utilized to determine whether the body part has pressed the input area of the device.

Claims

1. A method, comprising:

switching operation of a sensor between a first operation mode and a second operation mode, wherein

when operating in the first operation mode, the sensor provides a first output responsive to a force applied by an object, and

when operating in the second operation mode, the sensor provides a second output responsive to a proximity of the object.

2-31. -31. (canceled)