Touch-sensitive display with optical sensor and method

• US 9,513,737 B2
• Filed: 09/17/2010
• Issued: 12/06/2016
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Pemberton-Pigott, Nigel Patrick
• Primary Examiner(s): Faragalla, Michael
• Assistant Examiner(s): AU, SCOTT D
• Application Number:
  US12/884,936
• Publication Number:
  US 20120068971A1
• Time in Patent Office: 2,272 Days
• Field of Search: 345173-179
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers

Abstract

An electronic device includes a touch-sensitive display and a sensor configured to detect a force that results in depression of the touch-sensitive display. The sensor includes an optical device that receives a reflection of an optical signal, wherein the force affects the reflection.

Claims

1. An electronic device comprising:

a touch-sensitive display having a top surface, a bottom surface, and a side reflective surface; and

an optical device positioned to emit an optical signal at the side reflective surface of the touch-sensitive display and configured to detect a reflection of the optical signal from the side reflective surface of the touch-sensitive display, and detect a force that results in depression of the top surface based on a change to the optical signal due to the reflection, wherein the optical signal and the reflection have a same wavelength when a force is applied to the top surface and when a force is not applied to the top surface, and a distance between the side reflective surface of the touch-sensitive display and the optical device is substantially equal to a multiple of the same wavelength when a force is not applied to the top surface.

2. The electronic device of claim 1, wherein the optical device comprises an optical receiver and an optical emitter.

3. The electronic device of claim 1, wherein the change comprises a change in the distance between the back surface of the touch-sensitive display and the optical device.

4. The electronic device of claim 1, wherein the sensor comprises a plurality of optical receivers.

5. The electronic device of claim 1, wherein the sensor detects a change in the reflection due to bending of the touch-sensitive display resulting from the force.

6. The electronic device of claim 1, wherein the optical device comprises a first optical receiver that receives a first reflection from a first back surface of the touch-sensitive display and a second optical receiver that receives a second reflection from a second back surface of the touch-sensitive display.

7. The electronic device of claim 1, wherein the touch-sensitive display is depressible.

8. The electronic device of claim 1, wherein the optical device is disposed near a back surface of the touch-sensitive display.

9. The electronic device of claim 1, wherein the reflection has a first characteristic when the force does not meet a threshold, and wherein the reflection has a second characteristic when the force meets the threshold.

10. The electronic device of claim 9, wherein the first characteristic is a first amplitude and the second characteristic is a second amplitude that is less than the first amplitude.

11. The electronic device of claim 1, wherein at least one of:

(a) a reflective coating has been applied to the back surface to cause the optical signal to be reflected or (b) the back surface of the touch-sensitive display has been polished to cause the optical signal to be reflected.

12. An electronic device comprising:

a touch-sensitive display having a top surface, a bottom surface, and a side reflective surface;

a force sensor operable with the touch-sensitive display to detect a force exerted on the top surface and optical signals reflected from the side reflective surface of the touch-sensitive display, wherein the force sensor comprises an optical device that receives a reflection of an optical signal, wherein the reflection is affected by the force;

an optical emitter arranged to provide optical signals from which the reflection results; and

a processor configured to receive signals from the optical device and evaluate the signals to detect a variation in the optical signal after the reflection from the back surface of the touch-sensitive display, wherein the optical signal and the reflection have a same wavelength when a force is applied to the top surface and when a force is not applied to the top surface.

13. The electronic device of claim 12, wherein the optical device and the optical emitter are integrated into a single component.

14. The electronic device of claim 12, further configured to provide an indication of selection of a feature displayed on the touch-sensitive display when the variation meet a threshold.

15. A method comprising:

emitting an optical signal toward a side reflective surface of a touch-sensitive display, the touch-sensitive display having a top surface, a bottom surface, and the side reflective surface;

receiving a reflection of the optical signal reflected from the side reflective surface of the touch-sensitive display;

detecting a change in the optical signal due to the reflection, wherein the change is caused by a force exerted on the top surface that increases a distance between the touch-sensitive display and an optical detector, and the optical signal and the reflection have a same wavelength when a force is applied to the top surface and when a force is not applied to the top surface; and

providing an indication of the force when the change is detected.

16. The method of claim 15, further comprising comparing the change in the optical signal to a threshold, wherein the indication is provided when the change exceeds the threshold.