Capacitive touchpad with physical key function

• US 20060232559A1
• Filed: 12/13/2005
• Published: 10/19/2006
• Est. Priority Date: 04/19/2005
• Status: Abandoned Application

• Current Assignee: Elan Microelectronics Corporation
• Original Assignee: Elan Microelectronics Corporation
• Inventors: Chien, Yung-Lieh, Lii, Jia-Yih
• Application Number:
  US11/299,739
• Publication Number:
  US 20060232559A1
• Time in Patent Office: Days
• US Class Current: 345/168
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: H01H 13/807 characterised by the spatial arrangement of the contact sites, e.g. superimposed sites
• CPC Class Codes: H01H 2003/0293 with an integrated touch switch
• CPC Class Codes: H01H 2209/046 Properties of the spacer
• CPC Class Codes: H01H 2211/006 Individual areas
• CPC Class Codes: H01H 2225/002 superimposed
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/98 having a plurality of control members, e.g. keyboard
• CPC Class Codes: H03K 2217/960755 Constructional details of capacitive touch and proximity switches

Abstract

A capacitive touchpad with physical key function comprises a soft flexible first conductive layer; a second conductive layer; and a soft flexible insulator layer disposed between the first and the second conductive layers. The insulator layer has at least a through hole for the first conductive layer to connect to the second conductive layer while the touchpad is pressed and cause the voltages on the first or the second conductive layers to change and thus to trigger a predetermined key function.

Claims

1. A capacitive touchpad with physical key function, comprising:

a soft flexible first conductive layer;

a second conductive layer; and

a soft flexible insulator layer, disposed between the first and the second conductive layers, with at least a through hole for the first conductive layer connecting the second conductive layer while the touchpad is pressed to trigger a predetermined key function.

2. The touchpad of claim 1, wherein the first conductive layer comprises an axis sensor.

3. The touchpad of claim 2, wherein the second conductive layer comprises a second axis sensor.

4. The touchpad of claim 2, wherein the potential sensor detects the potential variation of the first or the second conductive layer to active the standby touchpad.

5. The touchpad of claim 1, wherein the first conductive layer comprises a first axis sensor and a second axis sensor.

6. The touchpad of claim 5, wherein the first conductive layer is a capacitive induction conductive layer.

7. The touchpad of claim 5, wherein the potential detector detects the potential variation of the first or the second conductive layer to active the standby touchpad.

8. The touchpad of claim 1, wherein the second conductive layer comprises soft flexible material.

9. The touchpad of claim 3, further comprising:

a first detector to detect the parasitic capacitance change of the first and the second conductive layers; and

a second detector to detect the voltage of the first conductive layer or the voltage of the second conductive layer.

10. The touchpad of claim 9, wherein the capacitive detector provides a first current to charge and discharge the first and the second conductive layers and to generate a voltage between the first and the second conductive layers.

11. The touchpad of claim 9, wherein the potential detector provides a first voltage to the first conductive layer and a second voltage to the second conductive layer.

12. The touchpad of claim 6, further comprising:

a first detector to detect the parasitic capacitance change of the first and the second axis sensors; and

a second detector to detect the voltage of the first conductive layer or the voltage of the second conductive layer.

13. The touchpad of claim 12, wherein the capacitive detector provides a first current to charge and discharge the first conductive layer to generate a voltage.

14. The touchpad of claim 12, wherein the potential detector provides a first voltage to the first conductive layer and a second voltage to the second conductive layer.

15. The touchpad of claim 1, wherein the insulator layer comprises a plurality of insulator balls.