KEYPAD APPARATUS

• US 20110221680A1
• Filed: 10/31/2008
• Published: 09/15/2011
• Est. Priority Date: 10/31/2008
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Technologies Oy (Nokia Corporation)
• Inventors: Tuovinen, Juhani, Karhiniemi, Marko
• Granted Patent: US 9,069,388 B2
• Time in Patent Office: Days
• US Class Current: 345/168
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: G06F 3/03 Arrangements for converting the position or the displacement of a member into a coded form
• 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: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/975 using a capacitive movable element
• CPC Class Codes: H03K 2217/960775 Emitter-receiver or "fringe" type detection, i.e. one or more field emitting electrodes and corresponding one or more receiving electrodes

Abstract

The disclosure relates to implementing different key types on a keypad or keyboard. The implementation can be enabled e.g. by an apparatus including a substrate (28) including a capacitive sensor element (29), the capacitive sensor element having a first electrode (24) forming a first capacitor with an object touching or coming into proximity of the first electrode, wherein the capacitive sensor element is configured to generate a first signal responsive to the object touching or coming into proximity of the capacitive sensor element, a first capacitor circuit coupled to at least the first electrode, and a dome (26) configured to complete, responsive to the dome being depressed, an electric circuit including at least the first capacitor and the first capacitor circuit to form a second capacitor circuit, wherein the second capacitor circuit is configured to generate a second signal.

Claims

1. An apparatus comprising:

a substrate comprising a capacitive sensor element, said capacitive sensor element having a first electrode forming a first capacitor with an object touching or coming into proximity of the first electrode, wherein the capacitive sensor element is configured to generate a first signal responsive to the object touching or coming into proximity of the capacitive sensor element;

a first capacitor circuit coupled to at least the first electrode; and

a dome configured to complete, responsive to the dome being depressed, an electric circuit comprising at least the first capacitor and the first capacitor circuit to form a second capacitor circuit, wherein the second capacitor circuit is configured to generate a second signal.

2. An apparatus according to claim 1, wherein the first capacitor circuit comprises a second capacitor coupled to the first electrode, and wherein the second capacitor circuit comprises the first capacitor and the second capacitor in parallel arrangement.

3. An apparatus according to claim 1, wherein the capacitive sensor element further comprises a second electrode.

4. An apparatus according to claim 3, wherein the first capacitor circuit comprises a third capacitor coupled to the first electrode and a fourth capacitor coupled to the second electrode, and the second capacitor circuit comprises the first capacitor, the third capacitor, and the fourth capacitor, wherein the third capacitor and the fourth capacitor are further coupled to signal ground.

5. An apparatus according to claim 3, wherein the capacitive sensor element is formed at an intersection of a first line and a second line, wherein the first electrode comprises a portion of the first line and the second electrode comprises a portion of the second line, and wherein said portion of the first line substantially overlaps said portion of the second line.

6. An apparatus according to claim 1, wherein the capacitive sensor element is formed at a location where the object touches or is in proximity of the first electrode.

7. An apparatus according to claim 1, further comprising:

a controller configured to receive and process the first signal and the second signal and to determine on the basis of said signals, whether a key touch action or a key press action is performed.

8. An apparatus according to claim 1, wherein the first capacitor circuit comprises at least one capacitor component.

9. An apparatus according to claim 1, wherein the first capacitor circuit is embodied on the substrate.

10. An apparatus according to claim 1, wherein the substrate is made of a material selected from a group consisting of polyethylene terephthalate, polyester, polytetrafluoroethylene, and glass.

11. A method comprising:

receiving a drive signal at a capacitive sensor element;

generating a first signal responsive to an object touching or coming into proximity of the capacitive sensor element, wherein the first signal is generated by the capacitive sensor element; and

generating a second signal responsive to a dome being depressed, wherein the second signal is generated by a capacitor circuit comprising the capacitive sensor element.

12. A method according to claim 11, further comprising:

receiving the first signal at a controller; and

determining on the basis of the first signal, that a key touch action is performed.

13. A method according to claim 11, further comprising:

receiving the second signal at a controller; and

determining on the basis of the second signal, that a key press action is performed.

14. A mobile device comprising:

a substrate comprising a capacitive sensor element, said capacitive sensor element having a first electrode forming a first capacitor with an object touching or coming into proximity of the first electrode, wherein the capacitive sensor element is configured to generate a first signal responsive to the object touching or coming into proximity of the capacitive sensor element;

a first capacitor circuit coupled to at least the first electrode; and

a dome configured to complete, responsive to the dome being depressed, an electric circuit comprising at least the first capacitor and the first capacitor circuit to form a second capacitor circuit, wherein the second capacitor circuit is configured to generate a second signal.