Apparatus for induced capacitor

• US 20060066585A1
• Filed: 03/02/2005
• Published: 03/30/2006
• Est. Priority Date: 09/24/2004
• Status: Abandoned Application

• Current Assignee: Holtek Semiconductor Incorporated
• Original Assignee: Holtek Semiconductor Incorporated
• Inventors: Lin, Yi-Chan
• Application Number:
  US11/068,981
• Publication Number:
  US 20060066585A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: H01H 2229/064 Eliminating tolerances
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2017/9613 using two electrodes per touch switch

Abstract

Disclosed is an apparatus for induced capacitor, an insulating substrate; and a plurality of capacitive sensing devices, being arranged on the insulating substrate in a matrix form, each of the plurality of capacitive sensing devices further comprising: a first electrode; and a second electrode, having an inner rim and an outer rim, being disposed circumferentially surrounding the first electrode while separating the second electrode from first electrode by a distance so as to form an equivalent capacitance therebetween, wherein a potential of each capacitive sensing device formed between the two electrodes is adjusted to be a predetermined value by adjusting the distance between the inner rim of the second electrode and the circumference of the first electrode while keeping the outer rim of the second electrode fixed.

Claims

1. A capacitive sensing device, comprising:

a first electrode; and

a second electrode, having an inner rim and an outer rim, being disposed circumferentially surrounding the first electrode while separating the second electrode from first electrode by a distance so as to form an equivalent capacitance therebetween.

2. The capacitive sensing device as recited in claim 1, wherein a potential is induced between the first and second electrodes while charging any one of the two electrodes.

3. The capacitive sensing device as recited in claim 2, wherein the potential of the capacitive sensing device is adjusted to be a predetermined value by adjusting the distance between the inner rim of the second electrode and the circumference of the first electrode while keeping the outer rim of the second electrode fixed.

4. The capacitive sensing device as recited in claim 3, wherein the distance between the inner rim of the second electrode and the first electrode is adjusted by varying the area of the first electrode.

5. The capacitive sensing device as recited in claim 3, wherein the distance between the inner rim of the second electrode and the first electrode is adjusted by varying the width of the second electrode.

6. The capacitive sensing device as recited in claim 1, wherein the first electrode has a structure of circular profile.

7. The capacitive sensing device as recited in claim 1, wherein the first electrode has a structure of polygonal profile.

8. An apparatus for induced capacitor, comprising:

an insulating substrate; and

a plurality of capacitive sensing devices, disposed on the insulating substrate in a matrix form, each capacitive sensing device further comprising;

a first electrode; and

a second electrode, having an inner rim and an outer rim, being disposed circumferentially surrounding the first electrode while separating the second electrode, from first electrode by a distance so as to form an equivalent capacitance therebetween.

9. The apparatus for induced capacitor as recited in claim 8, wherein a potential is induced between the first and second electrodes while charging any one of the two electrodes.

10. The apparatus for induced capacitor as recited in claim 9, wherein the potential of the capacitive sensing device is adjusted to be a predetermined value by adjusting the distance between the inner rim of the second electrode and the circumference of the first electrode while keeping the outer rim of the second electrode fixed.

11. The apparatus for induced capacitor as recited in claim 10, wherein the distance between the inner rim of the second electrode and the first electrode is adjusted by varying the area of the first electrode.

12. The apparatus for induced capacitor as recited in claim 10, wherein the distance between the inner rim of the second electrode and the first electrode is adjusted by varying the width of the second electrode.

13. The apparatus for induced capacitor as recited in claim 8, wherein the first electrode has a structure of circular profile.

14. The apparatus for induced capacitor as recited in claim 8, wherein the first electrode has structure of polygonal profile.

15. The apparatus for induced capacitor as recited in claim 9, wherein the apparatus for induced capacitor is a touch panel and the plural capacitive sensing devices are a plurality of touch keys of the touch panel, and the potential of one the plural capacitive sensing device is caused to decrease while the touch key corresponding to the capacitive sensing device is touched.

16. The apparatus for induced capacitor as recited in claim 8, wherein the insulating substrate is a FR4 board.

17. The apparatus for induced capacitor as recited in claim 8, wherein the insulating substrate is a membrane.