OPTICAL TRACKPAD MODULE AND METHOD OF USING SAME

• US 20110122061A1
• Filed: 11/25/2009
• Published: 05/26/2011
• Est. Priority Date: 11/25/2009
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Tong, Kuo-Feng, Stenmark, Fredrik Martin
• Granted Patent: US 8,390,569 B2
• Time in Patent Office: Days
• US Class Current: 345/157
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• 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 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/04847 Interaction techniques to control parameter settings, e.g. interaction with sliders or dials
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

An optical trackpad module is described herein. The module includes a light source and a trackpad that is optically coupled to the light source such that light from the light source can reach the trackpad. The trackpad is configured to receive an input object. The module also includes a sensor array that receives at least some of the light from the light source that is reflected off the input object. The sensor array is divided into sub-sections, and each sub-section corresponds to a portion of the trackpad. In addition, each sub-section detects at least translational movement of the input object on the corresponding trackpad portions to enable detection of rotational motion of the input object on the trackpad.

Claims

1. An optical trackpad module, comprising:

a light source;

a trackpad that is optically coupled to the light source, wherein the trackpad is configured to receive an input object; and

a sensor array that receives at least some of the light from the light source that is reflected off the input object;

wherein the sensor array is divided into sub-sections and each sub-section corresponds to a portion of the trackpad, wherein each sub-section detects at least translational movement of the input object on the corresponding trackpad portions to enable detection of the rotational motion of the input object on or above the trackpad.

2. The optical trackpad module according to claim 1, further comprising a processing unit that is operable to:

compare the detected translational movements of the input object on the trackpad portions; and

based on the comparison, determine a direction of the rotational motion of the input object on the trackpad.

3. The optical trackpad module according to claim 2, wherein at least part of the comparison comprises detecting translational movements of the input object that are opposite to one another.

4. The optical trackpad module according to claim 2, wherein the processing unit is alternatively operable to sequentially detect a series of translations over the trackpad portions over a period of time to enable the rotational motion to be detected.

5. The optical trackpad module according to claim 1, further comprising a shutter mechanism that is coupled to the sensor array and is configured to selectively permit signals from the sensor array to generate voltages that are proportional to the intensity of the light reflected off the input object.

6. The optical trackpad module according to claim 1, further comprising a depression detection component that is positioned underneath the trackpad and that detects a depression movement from the input object.

7. The optical trackpad module according to claim 1, wherein the trackpad acts as a volume control or playback control during a media mode or a zoom control during a camera mode.

8. The optical trackpad module according to claim 1, wherein the optical trackpad module is incorporated in a mobile device having a front surface and a side surface that is perpendicular to the front surface, wherein the front surface includes a display and wherein the trackpad is positioned on either the front surface or the side surface of the mobile device.

9. The optical trackpad module according to claim 1, wherein the light source is a light source that generates light outside the visible spectrum.

10. The optical trackpad module according to claim 1, wherein the number of sub-sections is equal to the number of corresponding portions of the trackpad.

11. An optical trackpad module, comprising:

a light source;

a trackpad that is positioned to receive non-visible light from the light source, wherein the trackpad includes an outer surface that receives an input object;

a sensor array that is positioned to receive non-visible light from the light source that is reflected off the finger when the input object is placed on the outer surface of the trackpad, wherein the sensor array is divided into sub-sections that are aligned with corresponding portions of the trackpad and each sub-section is configured to detect at least translational movement of the input object on the corresponding trackpad portions; and

a processor that is operable to compare the detected translational movements of the input object on the corresponding trackpad portions to determine whether the input object is moving in a substantially rotational manner.

12. The optical trackpad module according to claim 11, wherein the optical trackpad module is part of a mobile device that operates in a media mode or a camera mode and the processor is operable to control a volume or playback of a media application in the media mode or to control a zoom of a camera application in the camera mode based on the processor determining that the input object is moving in the substantially rotational manner.

13. The optical trackpad module according to claim 12, wherein the mobile device includes both a front surface and a side surface, wherein the side surface is substantially perpendicular to the front surface and wherein the outer surface of the trackpad is positioned on either the front surface or the side surface.

14. The optical trackpad module according to claim 11, wherein at least some of the detected translational movements are in substantially opposite directions with respect to one another.

15. The optical trackpad module according to claim 11, wherein the translational movements are sequentially detected over a period of time.

16. A method, comprising:

receiving light at a trackpad;

placing an object on or near an outer surface of the trackpad, thereby causing light received at the trackpad to be reflected off the object;

detecting the light reflected off the object at a sensor array that contains several sub-sections;

generating signals that are indicative of multiple translational movements of the object as the object moves on or above the outer surface of the trackpad in relation to the sub-sections;

comparing the generated signals; and

based on the comparison of the generated signals, detecting rotational movement of the object.

17. The method according to claim 16, further comprising adjusting a parameter of an application based on the detected rotational movement.

18. The method according to claim 17, wherein the application is a media program and the parameter is a volume or a selective playback of the media program or the application is a camera program and the parameter is a zoom feature of the camera program.

19. The method according to claim 16, further comprising generating voltages that are proportional to the intensity of the light reflected off the object based on signals from the sensor array.

20. The method according to claim 16, wherein the light received at the trackpad is outside the visible light spectrum.