System and a Method of Determining a Position of a Scattering/Reflecting Element on the Surface of a Radiation Transmisssive Element

• US 20090273794A1
• Filed: 03/29/2007
• Published: 11/05/2009
• Est. Priority Date: 03/30/2006
• Status: Active Grant

• Current Assignee: FlatFrog Laboratories AB
• Original Assignee: FlatFrog Laboratories AB
• Inventors: Østergaard, Jens Wagenblast Stubbe, Larsen, Niels Agersnap, Eliasson, Jonas Ove Philip
• Granted Patent: US 8,218,154 B2
• Time in Patent Office: Days
• US Class Current: 356/614
• CPC Class Codes: G02B 6/0016 Grooves, prisms, gratings, scattering particles or rough surfaces
• CPC Class Codes: G02B 6/003 Lens or lenticular sheet or layer
• CPC Class Codes: G06F 2203/04109 FTIR in optical digitiser, i.e. touch detection by frustrating the total internal reflection within an optical waveguide due to changes of optical properties or deformation at the touch location
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0423 using sweeping light beams, e.g. using rotating or vibrating mirror

Abstract

A system and a method of determining a position of a scattering/reflecting element on a surface of a radiation transmissive element adapted to transport scattered/reflected radiation toward one or more detectors. Radiation having different characteristics or properties is transmitted to different areas of the surface whereby the position of the touch may be determined from the radiation scattered/reflected.

Claims

1. A system for determining a position of a scattering/reflecting element, the system comprising:

a radiation transmissive element having a first surface adapted to be engaged by the scattering/reflecting element and a second surface opposite to the first surface,

a radiation provider adapted to provide radiation to or at the first surface in order for the scattering/reflecting element to be able to scatter/reflect radiation into the radiation transmissive element at the position on the first surface,

one or more detectors for detecting radiation scattered/reflected, at the position at the first surface, into the radiation transmissive element and guided by the radiation transmissive element toward the detector(s) and for outputting one or more corresponding signals,

a touch controller configured to determine the position on the basis of the signal(s) from the detector(s), wherein

the radiation provider is adapted to provide radiation with different properties/characteristics to different parts/areas of the first surface, at least one area of the first surface receiving radiation having at least two of the different properties/characteristics, and

the touch controller is adapted to determine the position on the basis of the properties/characteristics of the radiation detected by the detector(s).

2. A system according to claim 1, wherein the radiation provider comprises:

a plurality of radiation providers each providing radiation to a predetermined part/area of the first surface and each being adapted to provide radiation with a predetermined property/characteristic or with a property/characteristic selected from a predetermined group of properties.

3. A system according to claim 1, wherein the radiation provider is adapted to emit radiation into the radiation transmissive element and onto the first surface, and wherein the radiation transmissive element is adapted to guide radiation from the radiation provider to the first surface.

4. A system according to claim 1, wherein the radiation emitter comprises:

at least two scanning beam emitters, each of the at least two scanning beam emitters being configured to provide scanning beam directing radiation toward the first surface from a different location.

5. A system according to claim 4, wherein the detector(s) is/are positioned so as to be able to determine one or more points in time where the scanning beams emit radiation toward the detector(s), and wherein the touch controller is adapted to determine the position also on the basis of the point(s) in time.

6. A system according to claim 1, wherein the radiation provider comprises:

a plurality of radiation emitters each adapted to emit radiation through the second surface and onto the first surface, each radiation emitter or group of radiation emitters being controllable independently of other emitters or groups of emitters.

7. A system according to claim 6, wherein each radiation emitter comprises:

a radiation altering unit receiving radiation from one or more radiation emitters providing radiation to the radiation altering unit.

8. A system according to claim 7, wherein the radiation altering unit includes a plurality of radiation altering elements, and each radiation emitter provides radiation to a plurality of radiation altering elements, no radiation altering elements receiving radiation from more than one radiation emitter, and wherein the properties of the radiation emitters may be controlled independently of radiation altering properties of the individual radiation altering elements.

9. A system according to claim 6, wherein the radiation provider is adapted to control the radiation emitters or groups of radiation emitters to, sequentially in a predetermined order, emit radiation with a predetermined variation in wavelength or intensity, and wherein the touch controller is adapted to determine the position on the basis of a wavelength/intensity variation and a point in time of detection of the variation.

10. A system according to claim 6, wherein the radiation provider is adapted to control the emitters so as to provide, through the second surface and onto the first surface of the radiation transmissive element, radiation representing a predetermined image, and wherein the radiation provider is further adapted to alter the emission of one or more radiation emitters by addition or subtraction of a predetermined intensity or wavelength, the touch controller being adapted to determine the position as a position in which the intensity or wavelength has been altered.

11. A system according to claim 10, wherein the radiation provider is adapted to sequentially alter the emission of different groups of emitters.

12. A system according to claim 1, wherein the touch controller is adapted to:

determine a first position of a first scattering/reflecting element engaging the first surface and a second position of a second scattering/reflecting element engaging the first surface, and

control the radiation provider to provide first radiation at or on the first position and second radiation at or on the second position, the first radiation having a first property/characteristic or a property/characteristic selected from a first group of properties/characteristics, and the second radiation having a second property/characteristic or a property/characteristic selected from a second group of properties/characteristics, the first and second properties/characteristics being different and the first and second groups of properties/characteristics having no property/characteristic in common, and

wherein the touch controller is adapted to;

track the first position on the basis of signals from the detector and relating to radiation having the first property/characteristic or radiation having a property/characteristic from the first group, and

track the second position on the basis of signals from the detector and relating to radiation having the second property/characteristic or radiation having a property/characteristic from the second group.

13. A system according to claim 1, wherein the radiation provider is adapted to provide radiation with a property/characteristic which is a variation in the amplitude/wavelength of the radiation, the variation being at least 50 Hz.

14. A method for determining a position of a scattering/reflecting element, the method comprising:

providing, from a radiation provider, radiation to or at a first surface of a radiation transmissive element having a first surface adapted to be engaged by the scattering/reflecting element and a second surface opposite to the first surface,

the scattering/reflecting element scattering/reflecting radiation, at the position, from the radiation provider into the radiation transmissive element at the position on the first surface,

detecting radiation scattered/reflected by the scattering/reflecting element and guided by the radiation transmissive element toward the detector(s) and providing one or more corresponding signals,

determining the position on the basis of the signal(s), wherein

the radiation providing step comprises,

providing radiation with different properties/characteristics to different parts/areas of the first surface and providing radiation having at least two of the different properties/characteristics to at least one area, and

the determining step comprises,

determining the position on the basis of the properties/characteristics of the radiation detected.

15. A method according to claim 14, wherein the radiation providing step comprises:

each of a plurality of radiation emitters providing radiation to a predetermined part/area of the first surface and each providing radiation with a predetermined property/characteristic or with a property/characteristic selected from a predetermined group of properties.

16. A method according to claim 14, wherein the radiation providing step comprises:

providing at least two scanning beams directing radiation toward the first surface from different locations.

17. A method according to claim 16, wherein the detecting step comprises:

determining one or more points in time where the scanning beams emit radiation toward the detector(s), and wherein the determining step comprises,

determining the position also on the basis of the point(s) in time.

18. A method according to claim 14, wherein the radiation provider emits radiation into the radiation transmissive element and onto the first surface, and wherein the radiation transmissive element guides radiation from the radiation provider to the first surface.

19. A system according to claim 14, wherein the radiation providing step comprises:

each of a plurality of radiation emitters emitting radiation through the second surface and onto the first surface, each radiation emitter or group of radiation emitters being controlled independently of other emitters or groups of emitters.

20. A method according to claim 19, wherein the radiation providing step comprises:

providing each radiation emitter with a radiation altering element, all radiation altering elements receiving radiation from one or more radiation emitters providing radiation to a plurality of radiation altering elements.

21. A method according to claim 20, wherein each radiation emitter provides radiation to a plurality of radiation altering elements, no radiation altering elements receiving radiation from more than one radiation emitter, and wherein the properties of the radiation emitters is controlled independently of radiation altering properties of the individual radiation altering elements.

22. A system according to claim 19, wherein the radiation providing step comprises:

the radiation emitters or groups of radiation emitters emitting, sequentially in a predetermined order, radiation with a predetermined variation in wavelength or intensity, and wherein the determination step comprises,

determining the position on the basis of a wavelength/intensity variation and a point in time of detection of the variation.

23. A method according to claim 19, wherein the radiation providing step comprises:

the emitters providing, through the second surface and onto the first surface of the radiation transmissive element, radiation representing a predetermined image, and wherein the radiation providing step further comprises,

altering the emission of one or more radiation emitters by addition or subtraction of a predetermined intensity or wavelength, the determining step comprising,

determining the position as a position in which the intensity or wavelength has been altered.

24. A method according to claim 23, wherein the radiation providing step comprises:

sequentially altering the emission of different groups of emitters.

25. A method according to claim 14, comprising:

determining a first position of a first scattering/reflecting element and a second position of a second scattering/reflecting element,

providing first radiation at or on the first position and second radiation at or on the second position, the first radiation having a first property/characteristic or a property/characteristic selected from a first group of properties/characteristics, and the second radiation having a second property/characteristic or a property/characteristic selected from a second group of properties/characteristics, the first and second properties/characteristics being different and the first and second groups of properties/characteristics having no property/characteristic in common,

tracking the first position on the basis of signal(s) relating to detected radiation having the first property/characteristic or radiation having a property/characteristic from the first group, and

tracking the second position on the basis of signal(s) relating to detected radiation having the second property/characteristic or radiation having a property/characteristic from the second group.

26. A method according to claim 14, wherein the radiation providing step comprises:

providing radiation with a property/characteristic which is a variation in the amplitude/wavelength of the radiation, the variation being at least 50 Hz, such as at least 200 Hz, preferably at least 500 Hz, such as at least 750 Hz, preferably at least 1KHz, such as at least 5KHz, preferably at least 10KHz, such as at least 25 KHz, preferably at least 50KHz.

27. A system for determining a position of a scattering/reflecting element, the system comprising:

a radiation transmissive element having a first surface adapted to be engaged by the scattering/reflecting element and a second surface opposite to the first surface,

a monitor or display comprising a plurality of controllable radiation emitters each being adapted to provide radiation through the radiation transmissive element from the second surface toward a predetermined area of the first surface, the monitor or display being adapted to control the emitters to provide radiation representing predetermined images on the first surface,

one or more detectors for detecting radiation emitted by the monitor or display, scattered/reflected, at the position of the first surface, into the radiation transmissive element and guided by the radiation transmissive element toward the detector(s) and for outputting one or more corresponding signals,

a controller configured to determine the position on the basis of the signal(s) from the detector(s), wherein

the monitor or display is adapted to control predetermined radiation emitters or groups of radiation emitters to alter the wavelength/intensity of radiation emitted thereby in order for the wavelength/intensity of the emitters to deviate from that of an actual predetermined image, and

the controller is adapted to determine the position as a position in which the intensity/wavelength is altered in relation to that of the predetermined image.

28. A system according to claim 27, wherein the monitor or display is adapted to, sequentially, for each of a number of groups of radiation emitters, alter between providing the wavelength/intensity of the predetermined image and the altered intensity/wavelength, and wherein the controller is adapted to determine the position on the basis of:

a point in time in which the altered intensity/wavelength is detected,

a group of radiation emitters having altered the wavelength/intensity at that point in time, and

an area of the first surface in which a radiation emitter of the group of radiation emitters is adapted to provide radiation.

29. A system according to claim 28, wherein the controller is adapted to determine the position on the basis of an initial determination of an area and a subsequent repetition of the process of:

1. performing a determination of;

a. altering the radiation of the determined radiation emitters within the predetermined area,

b. determining whether an altered intensity/wavelength is detected,

c. if so, determining a reduced, predetermined area as a part of the predetermined area and repeating step 1. within the reduced, predetermined area,

d. if not, repeating step 1. with an amended predetermined area being the last predetermined area within which an altered intensity/wavelength was detected subtracted the predetermined area of step a.

30. A system according to claim 28, wherein the monitor or display is adapted to control all groups of radiation emitters to alter the wavelength/intensity sequentially and in a predetermined order.

31. A system according to claim 30, wherein the monitor or display is adapted to control the radiation emitters to alter the wavelength/intensity of the radiation emitted thereby in an order so that the radiation, at the first surface, is altered sequentially along a predetermined direction in a plane of the first surface.

32. A system according to claim 30, wherein the monitor or display is adapted to control the radiation emitters of the groups controlled to alter the radiation emitted thereby so that each of the radiation emitters of the group alters the intensity/wavelength in a different manner.

33. A system according to claim 31, wherein the monitor or display is adapted to alter the radiation of each radiation emitter in a predetermined manner and over a predetermined period of time.

34. A system according to claim 27, wherein the monitor or display is adapted to control radiation emitters, adapted to provide radiation to a predetermined area at or around a predetermined position, to alter the wavelength/intensity of radiation emitted thereby in a predetermined manner.

35. A system according to claim 34, wherein the monitor or display is adapted to control different ones of the radiation emitters to alter the wavelength/intensity differently, and wherein the controller is adapted to determine the position on the basis of the actual altering of the intensity/wavelength detected.

36. A method for determining a position of a scattering/reflecting element, the method comprising:

providing radiation through a radiation transmissive element, having a first surface adapted to be engaged by the scattering/reflecting element and a second surface opposite to the first surface, from the second surface toward a predetermined area of the first surface, the radiation being provided by a monitor or display comprising a plurality of controllable radiation emitters each providing radiation to a predetermined area of the first surface, the monitor or display controlling the emitters to provide radiation representing one or more predetermined images on the first surface,

detecting radiation emitted by the monitor or display, scattered/reflected by the scattering/reflecting element, at the position of the first surface, into the radiation transmissive element and guided by the radiation transmissive element toward one or more detector(s), and providing one or more corresponding signals, and

determining the position on the basis of the signal(s) from the detector(s), wherein

the monitor or display controls predetermined radiation emitters or groups of radiation emitters to alter the wavelength/intensity of radiation emitted thereby so that the wavelength/intensity of the emitters deviate from that of an actual predetermined image(s), and

the position is determined as a position in which the intensity/wavelength is altered in relation to that of the predetermined image.

37. A method according to claim 36, wherein the radiation emitters of each of a number of groups of radiation emitters, sequentially alters between providing the wavelength/intensity of the predetermined image and the altered intensity/wavelength,

and wherein the position is determined on the basis of:

a point in time in which the altered intensity/wavelength is detected,

a group of radiation emitters having altered the wavelength/intensity at that point in time, and

an area of the first surface in which a radiation emitter of the group of radiation emitters is adapted to provide radiation.

38. A method according to claim 37, wherein the position is determined on the basis of an initially determined area and a subsequent repetition of the process of:

1. performing a determination of;

a. altering the radiation of the determined radiation emitters within the predetermined area,

b. determining whether an altered intensity/wavelength is detected,

c. if so, determining a reduced, predetermined area as a part of the predetermined area and repeating step 1. within the reduced, predetermined area,

d. if not, repeating step 1. with an amended predetermined area being the last predetermined area within which an altered intensity/wavelength was detected subtracted the predetermined area of step a.

39. A method according to claim 37, wherein all groups of radiation emitters alter the wavelength/intensity sequentially and in a predetermined order.

40. A method according to claim 39, wherein the radiation emitters alter the wavelength/intensity of the radiation emitted thereby in an order so that the radiation, at the first surface, is altered sequentially along a predetermined direction in a plane of the first surface.

41. A method according to claim 39, wherein the monitor or display is adapted to control the radiation emitters of the groups controlled to alter the radiation emitted thereby so that each of the radiation emitters of the group alters the intensity/wavelength in a different manner.

42. A system according to claim 40, wherein the radiation of each radiation emitter in each group is altered in a predetermined manner and over a predetermined period of time.

43. A method according to claim 36, wherein radiation emitters providing radiation to a predetermined area at or around a predetermined position emit radiation with a wavelength/intensity altered in a predetermined manner.

44. A method according to claim 43, wherein different ones of the radiation emitters emit radiation with differently altered wavelength/intensity, and wherein the position is determined on the basis of the actual altering of the intensity/wavelength detected.

45. A system for determining a position of a scattering/reflecting element, the system comprising:

a radiation transmissive element having a first surface adapted to be engaged by the scattering/reflecting element and a second surface opposite to the first surface,

a radiation provider adapted to provide radiation to or at the first surface in order for the scattering/reflecting element to be able to scatter/reflect radiation into the radiation transmissive element at the position on the first surface,

one or more detectors for detecting radiation scattered/reflected, at the position at the first surface, into the radiation transmissive element and guided by the radiation transmissive element toward the detector(s) and for outputting one or more corresponding signals,

a controller configured to determine the position on the basis of the signal(s) from the detector(s), wherein

the radiation provider is adapted to provide at least two sweeping beams or radiation from two different positions, the sweeping beams impinging on the detector(s), and

the controller is adapted to determine the position on the basis of points of time of impinging of the sweeping beams on the detector(s) and of the detector(s) receiving scattered/reflected radiation.

46. A system according to claim 45, wherein the radiation provider is adapted to launch the sweeping beams into the radiation transmissive element, each beam being constituted by one or more collimated beams launched in at least substantially the same direction in the plane of the first surface, the one or more collimated beams of each beam covering, at the point of entrance into the transmissive element, at least 10% of a thickness of the transmissive element at that position.

47. A method for determining a position of a scattering/reflecting element, the method comprising:

providing, from a radiation provider, radiation to or at a first surface of a radiation transmissive element having a first surface adapted to be engaged by the scattering/reflecting element and a second surface opposite to the first surface,

the scattering/reflecting element scattering/reflecting radiation, at the position, from the radiation provider into the radiation transmissive element at the position on the first surface,

detecting radiation scattered/reflected by the scattering/reflecting element and guided by the radiation transmissive element toward the detector(s) and providing one or more corresponding signals,

determining the position on the basis of the signal(s), wherein

the radiation providing step comprises,

providing sweeping beams of radiation from at least two positions, the sweeping beams impinging on the detector(s), and

the determination step comprises,

performing the determination on the basis of points in time of impinging of the beams on the detector(s) and points in time of detecting scattered/reflected radiation.

48. A method according to claim 47, wherein the radiation providing step comprises:

launching the sweeping beams into the radiation transmissive element, each beam being constituted by one or more collimated beams launched in at least substantially the same direction in the plane of the first surface, the one or more collimated beams of each beam covering, at the point of entrance into the transmissive element, at least 10% of a thickness of the transmissive element at that position.