System And Method Of Determining A Position Of A Radiation Emitting Element

• US 20070201042A1
• Filed: 09/09/2004
• Published: 08/30/2007
• Est. Priority Date: 09/12/2003
• Status: Active Grant

• Current Assignee: FlatFrog Laboratories AB
• Original Assignee: FlatFrog Laboratories AB
• Inventors: Eliasson, Jonas, Østergaard, Jens
• Granted Patent: US 7,442,914 B2
• Time in Patent Office: Days
• US Class Current: 356/614
• CPC Class Codes: G06F 3/0386 for light pen
• CPC Class Codes: G06F 3/0428 by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421

Abstract

A method and a system for determining the position of a radiation emitter, which radiation emitter may be an actively radiation emitting stylus, pen, pointer, or the like or may be a passive, radiation scattering/reflecting/diffusing element, such as a pen, pointer, or a finger of an operator. The radiation from the emitter is reflected from that position toward the detector by a reflecting element providing multiple intensity spots on the detector providing sufficient information for determining the position. From the output of the detector, the position of the radiation emitter is determined.

Claims

1-23. -23. (canceled)

24. A system for determining a position of an element emitting radiation, the system comprising:

a radiation transmissive member adapted to receive, at a surface thereof, radiation emitted by the emitting element and guide radiation therein by total internal reflection,

an at least one-dimensional detector comprising a plurality of individual elements each being adapted to detect radiation and to provide a corresponding signal, the detector being adapted to receive radiation from a first edge part of the radiation transmissive member, the detector comprising one or more apertures, pinholes, or lenses provided between, on the one side, the detector elements and, on the other side, the emitting element and the reflecting element,

a reflecting element at a second edge part of the radiation transmissive member, the reflecting element adapted to reflect light incident thereon from inside the radiation transmissive member back into the radiation transmissive member and being adapted to reflect radiation emitted from the emitting element toward the elements of the detector, and

means for, on the basis of the signals of the detector relating to the radiation received directly from the emitting element and light emitted thereby and reflected toward the detector by the reflecting element, determining the position of the emitting element.

25. A system according to claim 24, wherein the detector comprises a single row of detecting element.

26. A system according to claim 24, wherein the reflecting element is straight.

27. A system according to claim 24, wherein the reflecting element is curved.

28. A system according to claim 24, wherein the reflecting element comprises at least two straight parts at an angle to each other, wherein each straight part of the reflecting means is adapted to reflect radiation emitted by the emitting means toward the detector.

29. A system according to claim 24, wherein the detector, reflecting means, any aperture/pinhole/lens, and emitting means are adapted to be positioned in a predetermined plane.

30. A system according to claim 29, wherein the detector and reflecting means are attached to a predetermined surface.

31. A system according to claim 29, wherein the emitting element is an element adapted to emit radiation from a radius thereof.

32. A system according to claim 30, wherein the emitting element comprises a stationary radiation emitter and a movable reflecting part, the stationary radiation emitter being positioned so as to emit radiation toward the movable reflecting element at least part of a field of view of the detector in a manner so that radiation is reflected, by the movable reflecting part, toward both the detector and the reflective element.

33. A system according to claim 24, wherein the emitting element is an element adapted to emit radiation from an end part thereof and into the transmissive member.

34. A system according to claim 24, wherein the emitting element comprises a radiation emitter and a scattering element, where the radiation emitter is positioned so as to emit radiation into the transmissive element and the scattering element is adapted to scatter radiation, such as at a surface of the transmissive element, toward the detector and the reflective element.

35. A system according to claim 24, wherein the determining means are adapted to determine a plurality of radiation intensity peaks over the detector and, from the positions of the peaks, determine the position of the emitting means.

46. A system according to claim 24, wherein the reflecting element and the detector are provided in a self-contained unit.

36. A method of determining a position of an element emitting electromagnetic radiation, the method comprising:

emitting the radiation into a radiation transmissive member adapted to guide radiation therein by total internal reflection,

detecting, using an at least one-dimensional detector comprising a plurality of individual elements each detecting radiation and providing a corresponding signal and at first edge part of the radiation transmissive member, radiation emitted from the first edge part and by the emitting element, wherein the detecting step comprises transmitting the radiation from the reflecting element and the emitting element through one or more apertures, pinholes, or lenses before detecting the radiation.

reflecting, at a second edge of the radiation transmissive member and using a reflecting element reflecting light incident thereon from inside the radiation transmissive member back into the radiation transmissive member, radiation emitted from the emitting element toward the detector, and

determining, on the basis of the signals of the detector relating to the radiation received directly from the emitting element and light emitted thereby and reflected toward the detector by the reflecting element, the position of the emitting element.

37. A method according to claim 36, wherein the detector comprises a single row of detecting elements.

38. A method according to claim 36, wherein the reflecting element comprises at least two straight parts at an angle to each other, wherein each straight part of the reflecting means reflects radiation emitted by the emitting means toward the detector.

39. A method according to claim 36, further comprising the step of positioning the detector, any aperture/pinhole/lens, the reflecting means and the emitting means in a predetermined plane.

40. A method according to claim 39, further comprising the step of attaching or fixing the detector, any aperture/pinhole/lens, the reflecting means, and reflecting means to a predetermined surface.

41. A method according to claim 39, wherein the emitting element emits radiation from a radius thereof.

42. A method according to claim 39, wherein the emitting element comprises a stationary radiation emitter and a moving reflecting element, the radiation emitter emitting radiation toward the reflecting element so that radiation is reflected toward both the detector and the reflective element.

43. A method according to claim 36, wherein the emitting element emits radiation from an end part thereof and into the transmissive member.

44. A method according to claim 36, wherein the emitting element comprises a radiation emitter and a scattering element, where the radiation emitter emits radiation into the transmissive element and the scattering element scatters, such as at a surface of the transmissive element, radiation toward the detector and the reflective element.

45. A method according to claim 36, wherein the determining step comprises determining a plurality of radiation intensity peaks over the detector and, from the positions of the peaks, determining the position of the emitting means.