INTEGRATED CONTACT SWITCH AND TOUCH SENSOR ELEMENTS

• US 20100149127A1
• Filed: 06/01/2009
• Published: 06/17/2010
• Est. Priority Date: 12/17/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: KOCALAR, Erturk, RATHNAM, Lakshman, FISHER, Joseph
• Granted Patent: US 8,395,590 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0362 with detection of 1D translations or rotations of an operating part of the device, e.g. scroll wheels, sliders, knobs, rollers or belts
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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

Abstract

An input device providing integrated contact switch and touch sensor elements is disclosed. A contact switch and touch sensor can be integrated so that they share a common sensor line, achieving space, cost and manufacturing savings over input devices that utilize distinct sensor lines for each of its sensor elements. By configuring a contact switch and touch sensor to share a common sensor line, a controller can use a single pin to scan both the contact switch and touch sensor elements, rather than using distinct pins to scan distinct sensor lines associated with each sensor element. By using fewer pins to scan the same number of sensor elements, a smaller controller can be used which can reduce the size and cost of the input device, and increase manufacturing throughput time associated with the input device.

Claims

1. An input device comprising:

a substrate comprising a first surface and a second surface,

a touch sensor element arranged on the first surface of the substrate,

a contact switch element arranged on the second surface of the substrate,

a common sensor line connected to the touch sensor element and the contact switch element, and

a controller configured to scan the common sensor line to detect an input associated with the touch sensor element or the contact switch element.

2. The input device of claim 1, wherein the controller is configured to perform, within a scan cycle, a first scan of the common sensor line for push button input and a second scan of the common sensor line for touch input.

3. The input device of claim 1, wherein the controller is configured to detect the input associated with the touch sensor element based on a capacitance scanned on the common sensor line.

4. The input device of claim 1, wherein the controller is configured to detect the input associated with the contact switch element based on a high voltage level or a low voltage level scanned on the common sensor line.

5. The input device of claim 1, wherein the controller is configured to detect the input associated with the contact switch element based on a capacitance scanned on the common sensor line.

6. The input device of claim 1, wherein the touch sensor element is aligned with the contact switch element on opposite sides of the substrate.

7. The input device of claim 1, wherein the contact switch element is associated with a mechanical push button.

8. A method comprising:

providing a common sensor line connected to a touch sensor element arranged on a first surface of a substrate and a contact switch element arranged on a second surface of the substrate,

capturing scan data based on a scan of the common sensor line for push button input, and

estimating scan data for the touch sensor element if the captured scan data indicates push button input

9. The method of claim 8, wherein the estimated scan data is based on scan data associated with the touch sensor element from one or more previous scan cycles.

10. The method of claim 8, wherein the estimated scan data is based on captured scan data associated with neighboring touch sensor elements.

11. The method of claim 10, wherein the estimated scan data is based on an average of the captured scan data associated with the neighboring touch sensor elements.

12. A method comprising:

capturing scan data from a sensor line common to a touch sensor element arranged on a first surface of a substrate and a contact switch element arranged on a second surface of the substrate,

determining that a touch input has occurred if the scan data lies between a first threshold level and a second threshold level, and

disregarding the scan data if the scan data exceeds the second threshold level.

13. The method of claim 12, wherein the scan data indicates a level of capacitance associated with the touch sensor element.

14. The method of claim 12, wherein scan data exceeding the second threshold indicates that the contact switch element is being pressed.

15. The method of claim 12, further comprising disregarding the scan data if the scan data fall below a third threshold level.

16. The method of claim 15, wherein the third threshold level indicates a noise threshold.

17. An input device comprising:

a substrate comprising a first surface and a second surface,

one or more sensor elements of a first type arranged on the first surface of the substrate,

one or more sensor elements of a second type arranged on the second surface of the substrate, and

a controller interface comprising multiple pins, wherein one of the pins is connected to one of the sensor elements of the first type and one of the sensor elements of the second type.

18. The input device of claim 17, wherein the one or more sensor elements of the first type are touch sensor elements, and the one or more sensor elements of the second type are contact switch elements.

19. The input device of claim 18, wherein the substrate comprises a multi-layer substrate, and the one or more touch sensor elements are arranged on a first layer of the multi-layer substrate.

20. The input device of claim 19, wherein the one or more contact switch elements are arranged on a second layer of the multi-layer substrate.

21. The input device of claim 20, wherein sensor lines connecting the one or more sensor elements of the first and second types to the pins are arranged between the first layer and the second layer of the multi-layer substrate.

22. The input device of claim 18, wherein the substrate comprises a single layer substrate.