capacitive control panel

Abstract

A control panel for proximity and force sensing, includes a cover layer, a first electrode layer including a first force sensor electrode, a second force sensor electrode positioned in a second electrode layer or on a support layer, and a dielectric substrate at least a portion of which is compressible and is positioned between the first and second force sensor electrodes. The support layer is positioned to support at the vicinity of the second force sensor electrode support location so that compression of the dielectric substrate and the separation of the first and second force sensor electrodes depends on the magnitude of a force applied to the cover layer. Touch sensor electrodes are positioned on one or more of the electrode layers such that their capacitance depends on proximity of an object such as a finger. Controllers measure the capacitance of the force and touch sensor electrodes respectively and output force and touch proximity signals.

Description

technical field [0001] The present invention relates to capacitive control panels. More particularly, the present invention relates to capacitive control panels incorporating touch-sensitive and force-sensitive input members. Background technique [0002] There is an increasing demand for robust and aesthetically pleasing control panels (user interfaces) for controlling devices. In recent years, capacitive sensing technology has long been used and accepted in this field. Common examples of devices incorporating capacitive control panels are touch-sensitive display screens and touch-sensitive keyboards / keypads, eg, for controlling consumer electronics / home appliances. [0003] Capacitive control panels are known to include touch sensitive inputs (eg capacitive position sensors) and force sensitive inputs (eg conventional buttons / switches). For example, versions of the "iPod mini" manufactured by Apple Computer Inc. have touch-sensitive scroll wheels overlying several mecha...

AI Technical Summary

Problems solved by technology

However, the problem with incorporating such force sensors into a control panel / user interface is that not only are they sensitive to directly applied force, such sensors will also be sensitive to changes in capacitance caused by nearby pointing objects such as the user's finger, Even when there is no press on the sensor (in the same way that a regular capacitive touch sensor responds to an approaching object)

Images