Optical touch apparatus with noise suppressing function and method of operating the same

• US 8,698,780 B2
• Filed: 06/10/2010
• Issued: 04/15/2014
• Est. Priority Date: 06/16/2009
• Status: Active Grant

• Current Assignee: Raydium Semiconductor Corporation
• Original Assignee: Raydium Semiconductor Corporation
• Inventors: Yen, Meng-Shin, Wang, William, Chou, Chung-Cheng
• Primary Examiner(s): Snyder, Adam J
• Application Number:
  US12/813,175
• Publication Number:
  US 20100315380A1
• Time in Patent Office: 1,405 Days
• Field of Search: 345/175, 178/18.09
• US Class Current: 345/175
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

An optical touch apparatus is disclosed. The optical touch apparatus comprises a light emitting module, a noise suppressing module, a light sensing module, and a processing module. The light emitting module emits at least one sensing beam, and the at least one sensing beam comprises a plurality of sensing rays. If an emitting angle of a specific sensing ray among the plurality of sensing rays toward a light sensor of the light sensing module is larger than a default value, the noise suppressing module will block the specific sensing ray from emitting into the light sensor. After the light sensing module generates a sensing result according to the condition of the light sensing module receiving the at least one sensing beam, the processing module will determine the position of a touch point according to the sensing result.

Claims

1. An optical touch apparatus, comprising:

a light emitting module, set at a first side of a surface of the optical touch apparatus, for emitting at least one sensing beam comprising a plurality of sensing rays;

a light sensing module, set at a second side different from the first side on the surface, the light sensing module comprising a plurality of light sensors;

a noise suppressing module, set at the second side and in front of the plurality of light sensors of the light sensing module, the noise suppressing module having a plurality of noise suppressing units arranged corresponding to the plurality of light sensors, and the plurality of noise suppressing units being opaque, a first noise suppressing unit of the plurality of noise suppressing units corresponding to a first light sensor of the plurality of light sensors and comprising a first portion and a second portion having different shapes, and the second portion being closer to the first light sensor than the first portion, if a specific sensing ray among the plurality of sensing rays is emitted to the first portion of the first noise suppressing unit, the specific sensing ray will be reflected away from the first light sensor by the first portion;

if the specific sensing ray is emitted to the second portion of the first noise suppressing unit, the specific sensing ray will be reflected into the first light sensor by the second portion; and

a processing module, coupled to the light sensing module, after the light sensing module generates a sensing result according to the condition of the light sensing module receiving the at least one sensing beam, the processing module determining the position of a touch point according to the sensing result.

2. The optical touch apparatus of claim 1, wherein if an emitting angle of the specific sensing ray toward the first light sensor is larger than a default value, the specific sensing ray is reflected by the first noise suppressing unit instead of being emitted into the first light sensor, if the emitting angle of the specific sensing ray toward the first light sensor is smaller than the default value and the specific sensing ray is emitted to the first noise suppressing unit, the first noise suppressing unit reflects the specific sensing ray to the first light sensor to increase the receiving strength of the first light sensor.

3. The optical touch apparatus of claim 1, wherein the noise suppressing module comprises a plurality of openings, the positions of the plurality of openings correspond to the plurality of light sensors respectively.

4. The optical touch apparatus of claim 3, wherein the appearance of the plurality of openings is designed to be lordosis, internal shrinkage, or wedge-shaped.

5. The optical touch apparatus of claim 3, wherein the design of the plurality of openings is changed according to the arrangement of the plurality of light sensors.

6. The optical touch apparatus of claim 1, wherein the plurality of noise suppressing units comprises a second noise suppressing unit adjacent to the first noise suppressing unit and the second noise suppressing unit also corresponds to the first light sensor, the second noise suppressing unit comprises a third portion and a fourth portion having different shapes, the third portion and the fourth portion are disposed corresponding to the first portion and the second portion respectively, and the fourth portion is closer to the first light sensor than the third portion;

if the specific sensing ray is emitted to the third portion of the second noise suppressing unit, the specific sensing ray will be reflected away from the first light sensor by the third portion;

if the specific sensing ray is emitted to the fourth portion of the second noise suppressing unit, the specific sensing ray will be reflected into the first light sensor by the fourth portion.

7. The optical touch apparatus of claim 1, wherein a surface of the noise suppressing module is coated with a light absorption material, when the emitting angle of the specific sensing ray toward the light sensor is larger than the default value and the specific sensing ray is emitted to the surface of the noise suppressing module, the surface absorbs the specific sensing ray to stop the specific sensing ray into the light sensor.

8. An optical touch apparatus, comprising:

a light emitting module, set at a first side of a surface of the optical touch apparatus, for emitting at least one sensing beam comprising a plurality of sensing rays;

a light sensing module, set at a second side different from the first side on the surface;

a noise suppressing module, set at the first side and in front of a plurality of light emitters of the light emitting module, the noise suppressing module having a plurality of noise suppressing units arranged corresponding to the plurality of light emitters, and the plurality of noise suppressing units being opaque, a first noise suppressing unit of the plurality of noise suppressing units corresponding to a first light emitter of the plurality of light emitters and comprising a first portion and a second portion having different shapes, and the first portion being closer to the first light emitter than the second portion, if a specific sensing ray among the plurality of sensing rays is emitted to the first portion of the first noise suppressing unit, the specific sensing ray will be reflected away from the light sensing module by the first portion;

if the specific sensing ray is emitted to the second portion of the first noise suppressing unit, the specific sensing ray will be reflected into the light sensing module by the second portion; and

a processing module, coupled to the light sensing module, after the light sensing module generates a sensing result according to the condition of the light sensing module receiving the at least one sensing beam, the processing module determining the position of a touch point according to the sensing result.

9. The optical touch apparatus of claim 8, wherein if an emitting angle of the specific sensing ray among the plurality of sensing rays toward the light sensing module is larger than a default value, the specific sensing ray is reflected by the first noise suppressing unit instead of being emitted into the light sensing module, if the emitting angle of the specific sensing ray toward the light sensing module is smaller than the default value and the specific sensing ray is emitted to the first noise suppressing unit, the first noise suppressing unit reflects the specific sensing ray to the light sensing module.

10. The optical touch apparatus of claim 8, wherein the noise suppressing module comprises a plurality of openings, the positions of the plurality of openings correspond to the plurality of light emitters respectively.

11. The optical touch apparatus of claim 10, wherein the appearance of the plurality of openings is designed to be lordosis, internal shrinkage, or wedge-shaped.

12. The optical touch apparatus of claim 10, wherein the design of the plurality of openings is changed according to the arrangement of the plurality of light emitters.

13. The optical touch apparatus of claim 8, wherein the plurality of noise suppressing units comprises a second noise suppressing unit adjacent to the first noise suppressing unit and the second noise suppressing unit also corresponds to the first light emitter, the second noise suppressing unit comprises a third portion and a fourth portion having different shapes, the third portion and the fourth portion are disposed corresponding to the first portion and the second portion respectively, and the third portion is closer to the first light emitter than the fourth portion;

if the specific sensing ray is emitted to the third portion of the second noise suppressing unit, the specific sensing ray will be reflected away from the light sensing module by the third portion;

if the specific sensing ray is emitted to the fourth portion of the second noise suppressing unit, the specific sensing ray will be reflected into the light sensing module by the fourth portion.

14. The optical touch apparatus of claim 8, wherein a surface of the noise suppressing module is coated with a light absorption material, when the emitting angle of the specific sensing ray toward the light sensor is larger than the default value and the specific sensing ray is emitted to the surface of the noise suppressing module, the surface absorbs the specific sensing ray to stop the specific sensing ray into the light sensor.

15. A method of operating an optical touch apparatus, the optical touch apparatus comprising a light emitting module, a light sensing module, a noise suppressing module, and a processing module, the light emitting module and the light sensing module being set at a first side and a second side of a surface of the optical touch apparatus respectively, the noise suppressing module being set at the second side and in front of a plurality of light sensors of the light sensing module, the noise suppressing module having a plurality of noise suppressing units arranged corresponding to the plurality of light sensors, and the plurality of noise suppressing units being opaque, a first noise suppressing unit of the plurality of noise suppressing units corresponding to a first light sensor of the plurality of light sensors and comprising a first portion and a second portion having different shapes, and the second portion being closer to the first light sensor than the first portion, the method comprising the steps of:

the light emitting module emitting at least one sensing beam comprising a plurality of sensing rays;

if a specific sensing ray among the plurality of sensing rays is emitted to the first portion of the first noise suppressing unit, the specific sensing ray will be reflected away from the first light sensor by the first portion;

if the specific sensing ray is emitted to the second portion of the first noise suppressing unit, the specific sensing ray will be reflected into the first light sensor by the second portion;

the light sensing module generating a sensing result according to the condition of the light sensing module receiving the at least one sensing beam; and

the processing module determining the position of a touch point according to the sensing result.

16. The method of claim 15, wherein if an emitting angle of the specific sensing ray toward the first light sensor is larger than a default value, the specific sensing ray is reflected by the first noise suppressing unit instead of being emitted into the first light sensor, if the emitting angle of the specific sensing ray toward the first light sensor is smaller than the default value and the specific sensing ray is emitted to the first noise suppressing unit, the first noise suppressing unit reflects the specific sensing ray to the first light sensor to increase the receiving strength of the first light sensor.

17. The method of claim 15, wherein the noise suppressing module comprises a plurality of openings, the positions of the plurality of openings correspond to the plurality of light sensors respectively.

18. The method of claim 17, wherein the appearance of the plurality of openings is designed to be lordosis, internal shrinkage, or wedge-shaped.

19. The method of claim 17, wherein the design of the plurality of openings is changed according to the arrangement of the plurality of light sensors.

20. The method of claim 15, wherein the plurality of noise suppressing units comprises a second noise suppressing unit adjacent to the first noise suppressing unit and the second noise suppressing unit also corresponds to the first light sensor, the second noise suppressing unit comprises a third portion and a fourth portion having different shapes, the third portion and the fourth portion are disposed corresponding to the first portion and the second portion respectively, and the fourth portion is closer to the first light sensor than the third portion;

if the specific sensing ray is emitted to the third portion of the second noise suppressing unit, the specific sensing ray will be reflected away from the first light sensor by the third portion;

if the specific sensing ray is emitted to the fourth portion of the second noise suppressing unit, the specific sensing ray will be reflected into the first light sensor by the fourth portion.

21. The method of claim 15, wherein a surface of the noise suppressing module is coated with a light absorption material, when the emitting angle of the specific sensing ray toward the light sensor is larger than the default value and the specific sensing ray is emitted to the surface of the noise suppressing module, the surface absorbs the specific sensing ray to stop the specific sensing ray into the light sensor.

22. A method of operating an optical touch apparatus, the optical touch apparatus comprising a light emitting module, a light sensing module, a noise suppressing module, and a processing module, the light emitting module and the light sensing module being set at a first side and a second side of a surface of the optical touch apparatus respectively, the noise suppressing module being set at the first side and in front of a plurality of light emitters of the light emitting module, the noise suppressing module having a plurality of noise suppressing units arranged corresponding to the plurality of light emitters, and the plurality of noise suppressing units being opaque, a first noise suppressing unit of the plurality of noise suppressing units corresponding to a first light emitter of the plurality of light emitters and comprising a first portion and a second portion having different shapes, and the first portion being closer to the first light emitter than the second portion, the method comprising the steps of:

the light emitting module emitting at least one sensing beam comprising a plurality of sensing rays;

if a specific sensing ray among the plurality of sensing rays is emitted to the first portion of the first noise suppressing unit, the specific sensing ray will be reflected away from the light sensing module by the first portion;

if the specific sensing ray is emitted to the second portion of the first noise suppressing unit, the specific sensing ray will be reflected into the light sensing module by the second portion;

the light sensing module generating a sensing result according to the condition of the light sensing module receiving the at least one sensing beam; and

the processing module determining the position of a touch point according to the sensing result.

23. The method of claim 22, wherein if an emitting angle of the specific sensing ray among the plurality of sensing rays toward the light sensing module is larger than a default value, the specific sensing ray is reflected by the first noise suppressing unit instead of being emitted into the light sensing module, if the emitting angle of the specific sensing ray toward the light sensing module is smaller than the default value and the specific sensing ray is emitted to the first noise suppressing unit, the first noise suppressing unit reflects the specific sensing ray to the light sensing module.

24. The method of claim 22, wherein the noise suppressing module comprises a plurality of openings, the positions of the plurality of openings correspond to the plurality of light emitters respectively.

25. The method of claim 24, wherein the appearance of the plurality of openings is designed to be lordosis, internal shrinkage, or wedge-shaped.

26. The method of claim 24, wherein the design of the plurality of openings is changed according to the arrangement of the plurality of light emitters.

27. The method of claim 22, wherein the plurality of noise suppressing units comprises a second noise suppressing unit adjacent to the first noise suppressing unit and the second noise suppressing unit also corresponds to the first light emitter, the second noise suppressing unit comprises a third portion and a fourth portion having different shapes, the third portion and the fourth portion are disposed corresponding to the first portion and the second portion respectively, and the third portion is closer to the first light emitter than the fourth portion;

if the specific sensing ray is emitted to the third portion of the second noise suppressing unit, the specific sensing ray will be reflected away from the light sensing module by the third portion;

if the specific sensing ray is emitted to the fourth portion of the second noise suppressing unit, the specific sensing ray will be reflected into the light sensing module by the fourth portion.

28. The method of claim 22, wherein a surface of the noise suppressing module is coated with a light absorption material, when the emitting angle of the specific sensing ray toward the light sensor is larger than the default value and the specific sensing ray is emitted to the surface of the noise suppressing module, the surface absorbs the specific sensing ray to stop the specific sensing ray into the light sensor.