APPARATUS AND METHOD FOR OPTICAL PROXIMITY SENSING AND TOUCH INPUT CONTROL

• US 20100245289A1
• Filed: 03/31/2009
• Published: 09/30/2010
• Est. Priority Date: 03/31/2009
• Status: Abandoned Application

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Svajda, Miroslav
• Application Number:
  US12/415,199
• Publication Number:
  US 20100245289A1
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: H03K 17/9631 using a light source as part of the switch

Abstract

Systems, circuits and methods are shown for optical proximity sensing and touch input control involving mounting light sources and an optical receiver with a touch input device, activating a first light source and measuring a first reflected light signal from an object using the receiver to obtain a first measured reflectance value, activating a second light source and measuring a second reflected light signal from the object using the receiver to obtain a second measured reflectance value, determining an approximate position of the object based on the first and second measured reflectance values, determining whether the position of the object is within a predetermined proximity area to the touch input device, and activating the touch input device if the object is within the predetermined proximity area or selectively activating or scanning part of the touch input device based on the position of the object.

Claims

1. A touch input and optical proximity sensing system, the system comprising:

first and second light sources;

a first optical receiver configured to receive a first reflected light signal from an object when the first light source is activated and output a first measured reflectance value corresponding to an amplitude of the first reflected light signal and receive a second reflected light signal from the object when the second light source is activated and output a second measured reflectance value corresponding to an amplitude of the second reflected light signal;

a first touch input device, where the first and second light sources and the first optical receiver are in predetermined positions relative to the first touch input device; and

a controller in communication and control of the first and second light sources, the first optical receiver and the first touch input device, where the controller is configured to independently activate the first and second light sources to produce the first and second reflected light signals and capture the first and second measured reflectance values from the first optical receiver, and the controller is further configured to determine a first approximate position of the object based on the first and second measured reflectance values and determine whether the first approximate position of the object is within a predetermined proximity area to the first touch input device and, if the object is within the predetermined proximity area, the controller is configured to activate at least a portion of the first touch input device.

2. The touch input and optical proximity sensing system of claim 1, wherein:

the first optical receiver is configured to receive a third reflected light signal from an object when the first light source is activated and output a third measured reflectance value corresponding to an amplitude of the third reflected light signal and receive a fourth reflected light signal from the object when the second light source is activated and output a fourth measured reflectance value corresponding to an amplitude of the fourth reflected light signal; and

the controller is configured to independently activate the first and second light sources to produce the third and fourth reflected light signals and capture the third and fourth measured reflectance values from the first optical receiver, and the controller is further configured to determine a second approximate position of the object based on the third and fourth measured reflectance values and compare the first and second approximate positions in order determine whether the object is approaching the first touch input device and, activate the portion of the first touch input device when the object is approaching the first touch input device.

3. The touch input and optical proximity sensing system of claim 2, wherein:

the controller is further configured to identify a gesture of the object based on the first and second approximate positions.

4. The touch input and optical proximity sensing system of claim 3, wherein:

the controller is further configured to capture user touch input from the first touch input device and determine whether the gesture of the object is consistent with the user touch input.

5. The touch input and optical proximity sensing system of claim 1, wherein:

the first touch input device is configured to have regions that can be selectively activated by the controller; and

the controller is configured to selectively activate the first portion of the first touch input device based on the first approximate position of the object.

6. The touch input and optical proximity sensing system of claim 5, wherein the controller is configured to selectively activate the portion of the first touch input device by selectively scanning the portion of the first touch input device.

7. The touch input and optical proximity sensing system of claim 5, wherein:

the system further includes a third light source;

the first optical receiver is configured to receive a fifth reflected light signal from the object when the third light source is activated and output a fifth measured reflectance value corresponding to an amplitude of the fifth reflected light signal; and

the controller is in communication and control of the third light source and is configured to independently activate the third light source to produce the fifth reflected light signal and capture the fifth measured reflectance value from the first optical receiver, and the controller is further configured to determine the first approximate position of the object based on the first, second and fifth measured reflectance values and selectively activate the portion of the first touch input device based on the first approximate position derived from the first, second and fifth measured reflectance values.

8. The touch input and optical proximity sensing system of claim 1, wherein:

the system includes a second touch input device; and

the controller is in communication and control of the second touch input device and is configured to selectively activate at least one of the first and second touch input devices based on the first approximate position of the object.

9. The touch input and optical proximity sensing system of claim 1, wherein the controller is configured to activate the portion of the first touch input device by scanning the portion of the first touch input device.

10. The touch input and optical proximity sensing system of claim 1, wherein the system further includes:

a second optical receiver mounted in a predetermined position with respect to the first and second light sources and the first input device and configured to receive reflected light signals from the object when at least one of the first and second light sources is activated and output a first measured reflectance value corresponding to an amplitude of the received reflected light signals; and

the controller is in communication and control of the first second optical receiver, where the controller is further configured to capture the measured reflectance values from the second optical receiver and determine the first approximate position of the object based on the first and second measured reflectance values and the measured reflectance values from the second optical receiver in order to determine whether the first approximate position of the object is within the predetermined proximity area to the first touch input device.

11. A method for optical proximity sensing and touch input control, the method comprising the steps of:

mounting a plurality of light sources and a first optical receiver in predetermined position relative to a first touch input device;

activating at least a first one of the light sources and measuring an amplitude of a first reflected light signal from an object using the first optical receiver to obtain a first measured reflectance value;

activating at least a second one of the light sources and measuring an amplitude of a second reflected light signal from the object using the first optical receiver to obtain a second measured reflectance value;

determining a first approximate position of the object based on the first and second measured reflectance values;

determining whether the first approximate position of the object is within a predetermined proximity area to the first touch input device; and

activating at least a portion of the first touch input device if the object is within the predetermined proximity area.

12. The method for optical proximity sensing and touch input control of claim 11, wherein the method includes the steps of:

activating the first one of the light sources and measuring an amplitude of a third reflected light signal from the object using the first optical receiver to obtain a third measured reflectance value;

activating the second one of the light sources and measuring an amplitude of a fourth reflected light signal from the object using the first optical receiver to obtain a fourth measured reflectance value;

determining a second approximate position of the object based on the third and fourth measured reflectance values; and

comparing the first and second approximate positions in order determine whether the object is approaching the first touch input device; and

wherein;

the step of activating at least a portion of the first touch input device further includes activating the portion of the first touch input device when the object is approaching the first touch input device.

13. The method for optical proximity sensing and touch input control of claim 12, where the method includes the step of identifying a gesture of the object based on the first and second approximate positions.

14. The method for optical proximity sensing and touch input control of claim 13, where the method includes the steps of capturing user touch input from the first touch input device and determining whether the gesture of the object is consistent with the user touch input.

15. The method for optical proximity sensing and touch input control of claim 11, wherein the first touch input device is configured to have regions that can be selectively activated and the step of activating the portion of the first touch input device further comprises selectively activating the first portion of the first touch input device based on the first approximate position of the object.

17. The method for optical proximity sensing and touch input control of claim 15, wherein:

the method includes the steps of activating a third one of the light sources and measuring an amplitude of a fifth reflected light signal from the object using the first optical receiver to obtain a fifth measured reflectance value;

the step of determining a first approximate position of the object further comprises determining the first approximate position of the object based on the first, second and fifth measured reflectance values; and

the step of selectively activating the portion of the first touch input device based on the first approximate position further includes selectively activating the portion of the first touch input device based on the first approximate position derived from the first, second and fifth measured reflectance values.

18. The method for optical proximity sensing and touch input control of claim 11, wherein:

the method includes mounting a second touch input device in predetermined position relative to the plurality of light sources and the first optical receiver; and

the step of determining whether the first approximate position of the object is within a predetermined proximity area to the first touch input device further includes determining whether the first approximate position of the object is within another predetermined proximity area to the second touch input device; and

the method includes the step of activating at least a portion of the second touch input device if the object is within the another predetermined proximity area.

19. The method for optical proximity sensing and touch input control of claim 11, wherein the step of activating at least a portion of the first touch input device further comprises scanning the portion of the first touch input device.

20. The method for optical proximity sensing and touch input control of claim 11, wherein:

the method includes mounting a second optical receiver in a predetermined position with respect to the first and second light sources and the first touch input device, where the second optical receiver is configured to receive reflected light signals from the object when at least one of the first and second light sources is activated and output a first measured reflectance value corresponding to an amplitude of the received reflected light signals; and

the step of determining the first approximate position of the object further comprises determining the first approximate position of the object based on the first and second measured reflectance values and the measured reflectance values from the second optical receiver in order to determine whether the first approximate position of the object is within the predetermined proximity area to the first touch input device.

16. The method for optical proximity sensing and touch input control of claim M5, wherein the step of selectively activating the portion of the first touch input device further comprises selectively scanning the portion of the first touch input device.

21. An optical proximity sensing and touch input control system, the system comprising:

a plurality of light sources and at least one optical receiver mounted in predetermined position relative to at least one touch input device;

means for activating at least a first one of the light sources and measuring an amplitude of a first reflected light signal from an object using at least one optical receiver to obtain a first measured reflectance value;

means for activating at least a second one of the light sources and measuring an amplitude of a second reflected light signal from the object using at least one optical receiver to obtain a second measured reflectance value;

means for determining a first approximate position of the object based on the first and second measured reflectance values;

means for determining whether the first approximate position of the object is within a predetermined proximity area to at least one touch input device; and

means for activating at least a portion of at least one touch input device if the object is within the predetermined proximity area.