TOUCHLESS INTERFACES

• US 20120299820A1
• Filed: 10/25/2010
• Published: 11/29/2012
• Est. Priority Date: 10/23/2009
• Status: Active Grant

• Current Assignee: Elliptic Laboratories AS
• Original Assignee: Elliptic Laboratories AS
• Inventors: Dahl, Tobias
• Granted Patent: US 9,367,178 B2
• Time in Patent Office: Days
• US Class Current: 345/156
• CPC Class Codes: G01S 15/003 Bistatic sonar systems; Multistatic sonar systems
• CPC Class Codes: G01S 15/876 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S15/872 takes precedence
• CPC Class Codes: G06F 2203/04108 Touchless 2D- 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 without distance measurement in the Z direction
• CPC Class Codes: G06F 3/011 Arrangements for interaction with the human body, e.g. for user immersion in virtual reality blind teaching G09B21/00
• CPC Class Codes: G06F 3/043 using propagating acoustic waves
• CPC Class Codes: G06F 3/0436 in which generating transducers and detecting transducers are attached to a single acoustic waves transmission substrate

Abstract

The shape or position of an object is estimated using a device comprising one or more transmitters and one or more receivers, forming a set of at least two transmitter-receiver combinations. Signals are transmitted from the transmitters, through air, to the object. They are reflected by the object and received by the receivers. A subset of the transmitter-receiver combinations which give rise to a received signal meeting a predetermined clarity criterion is determined. The positions of points on the object are estimated using substantially only signals from the subset of combinations.

Claims

1. A method of estimating the shape and/or position of an object using a device comprising one or more transmitters and one or more receivers, forming a set of at least two transmitter-receiver combinations, said method comprising:

transmitting signals from the transmitter(s), said signals travelling through air to the object, being reflected by the object and received by the receiver(s);

determining a subset of the transmitter-receiver combinations which give rise to a received signal meeting a predetermined clarity criterion; and

estimating positions for a plurality of points on said object using substantially only signals from said subset of combinations.

2. A method as claimed in claim 1 wherein the object is all or part of a human hand.

3. A method as claimed in claim 1 or 2 wherein the clarity criterion is such that it is not met by a transmitter-receiver combination when a reflective surface other than a surface of the object is at the same or similar time-of-flight distance, for that transmitter-receiver combination, as the object.

4. A method as claimed in any preceding claim comprising determining whether a received signal meets the predetermined clarity criterion by determining whether the signal matches a leading-edge filter.

5. A method as claimed in any preceding claim wherein the transmitted signals are ultrasonic signals.

6. A method as claimed in any preceding claim wherein the transmitted signals comprise a series of pulses.

7. A method as claimed in any preceding claim wherein the transmitted signals comprise chirps.

8. A method as claimed in any preceding claim wherein each of said transmitter-receiver combinations comprises a plurality of transmitters and/or a plurality of receivers.

9. A method as claimed in claim 8 comprising determining, for a transmitter-receiver combination that comprises a plurality of receivers, directional information for the reflected signals by comparing delays between the times of receipt of the reflected signals at respective receivers of the transmitter-receiver combination.

10. A method as claimed in claim 8 or 9 comprising, for a transmitter-receiver combination that comprises a plurality of transmitters, transmitting signals from respective transmitters of the transmitter-receiver combination with relative time delays, in order to steer the transmission in a predetermined direction.

11. A method as claimed in any preceding claim wherein the device comprises a plurality of receivers, and wherein at least some of the receivers are provided in a group in which the maximum distance between any receiver and its nearest neighbour is less than the longest wavelength transmitted by the device in normal use.

12. A method as claimed in any preceding claim comprising transmitting respective signals from a plurality of transmitters in sequence, and using the signals to determine transmitter-receiver combinations for which the clarity criterion is met.

13. A method as claimed in claim 12 comprising using said signals to determine transmitter-receiver pairs for which the clarity criterion is met.

14. A method as claimed in any preceding claim wherein transmitters and receivers of the device are laid out in a regularly-spaced array.

15. A method as claimed in claim 14 wherein said array comprises at least two parallel rows of transducers.

16. A device configured to estimate the shape and/or position of an object, the device comprising:

one or more transmitters and one or more receivers forming a set of at least two transmitter-receiver combinations, said transmitters being arranged to transmit signals;

means for determining a subset of the transmitter-receiver combinations which give rise to a received signal meeting a predetermined clarity criterion; and

means for estimating positions for a plurality of points on said object using substantially only signals from said subset of combinations.

17. A device as claimed in claim 16 wherein the clarity criterion is such that it is not met by a transmitter-receiver combination when a reflective surface other than a surface of the object is at the same or similar time-of-flight distance, for that transmitter-receiver combination, as the object.

18. A device as claimed in claim 16 or 17 configured to determine whether a received signal meets the predetermined clarity criterion by determining whether the signal matches a leading-edge filter.

19. A device as claimed in any of claims 16 to 18 wherein said transmitters are arranged to transmit ultrasonic signals.

20. A device as claimed in any of claims 16 to 19 configured to transmit a series of pulses.

21. A device as claimed in any of claims 16 to 20 configured to transmit chirps.

22. A device as claimed in any of claims 16 to 21 wherein each of said transmitter-receiver combinations comprises a plurality of transmitters and/or a plurality of receivers.

23. A device as claimed in claim 22 configured to determine, for a transmitter-receiver combination that comprises a plurality of receivers, directional information for received reflected signals by comparing delays between the times of receipt of the reflected signals at respective receivers of the transmitter-receiver combination.

24. A device as claimed in claim 22 or 23 configured, for a transmitter-receiver combination that comprises a plurality of transmitters, to transmit signals from respective transmitters of the transmitter-receiver combination with relative time delays, in order to steer the transmission in a predetermined direction.

25. A device as claimed in any of claims 16 to 24 comprising a plurality of receivers, wherein at least some of the receivers are provided in a group in which the maximum distance between any receiver and its nearest neighbour is less than the longest wavelength the device is configured to transmit in normal use.

26. A device as claimed in any of claims 16 to 25 configured to transmit respective signals from a plurality of transmitters in sequence, and to use the signals to determine transmitter-receiver combinations for which the clarity criterion is met.

27. A device as claimed in claim 26 configured to use said signals to determine transmitter-receiver pairs for which the clarity criterion is met.

28. A device as claimed in any of claims 16 to 27 comprising transmitters and receivers that are laid out in a regularly-spaced array.

29. A device as claimed in claim 28 wherein said array comprises at least two parallel rows of transducers.

30. A computer software product configured, when run on a device comprising one or more transmitters and one or more receivers, forming a set of at least two transmitter-receiver combinations, to operate the device to estimate the shape and/or position of an object, the software product comprising:

instructions for transmitting signals from the transmitter(s);

logic for determining a subset of the transmitter-receiver combinations which give rise to a received signal meeting a predetermined clarity criterion; and

logic for estimating positions for a plurality of points on said object using substantially only signals from said subset of combinations.

31. A handheld device comprising a plurality of acoustic transducers as part of a user interface, said transducers being arranged in at least two parallel rows.

32. A device as claimed in claim 31 wherein the rows are parallel with an edge of the device.

33. A device as claimed in claim 31 or 32 wherein each row comprises at least three transducers.

34. A device as claimed in any of claims 31 to 33 wherein each row is longer than the distance between the rows.

35. A device as claimed in any of claims 31 to 34 wherein the transducers are substantially regularly spaced along the rows.

36. A device as claimed in any of claims 31 to 35 wherein the distance between the rows is less than half the maximum wavelength transmitted by one or more of the transducers in use.

37. A device as claimed in any of claims 31 to 36 comprising three or more parallel rows of transducers.

38. A device as claimed in any of claims 31 to 37 comprising a display or interaction surface.

39. A device as claimed in claim 38 wherein both rows of transducers are on the same side of the display or interaction surface.

40. A device as claimed in claim 38 or 39 wherein the display or interaction surface is rectangular with the two rows of transducers being parallel to an edge of the rectangle.

41. A device as claimed in any of claims 38 to 40 wherein the screen or interaction surface is surrounded by two concentric rings of transducer elements.

42. A device as claimed in claim 41 wherein the two concentric rings conform to the shape of the screen or interaction surface.

43. A device as claimed in any of claims 38 to 42 wherein the display or interaction surface is arranged to transmit an acoustic signal.

44. A device as claimed in any of claims 38 to 43 having a transmitting surface which comprises a display screen, or which is disposed in substantially overlapping relationship with a display screen, and which is arranged to transmit an acoustic signal.

45. A device as claimed in claim 44 wherein the transmitting surface is further arranged to receive a reflection of an acoustic signal from an object of interest.

46. A method of operating a handheld device comprising a plurality of acoustic transducers arranged in at least two parallel rows, the method comprising using acoustic signals transmitted from and/or received by said transducers to estimate the shape and/or position of an object, and/or to characterise the motion of an object.

47. A method as claimed in claim 46 wherein the device has a transmitting surface which comprises a display screen, or which is disposed in substantially overlapping relationship with a display screen, the method further comprising transmitting an acoustic signal from the transmitting surface.

48. A method as claimed in claim 47 comprising using the transmitting surface as a receiving surface to receive a reflection of the acoustic signal from an object of interest.

49. A computer software product configured, when run on a handheld device comprising a plurality of acoustic transducers arranged in at least two parallel rows, to use acoustic signals transmitted from and/or received by said transducers to estimate the shape and/or position of an object, and/or to characterise the motion of an object.

50. Apparatus for characterising the shape, location or motion of an object, comprising:

a display screen;

a transmitting surface comprising the display screen, or being disposed in substantially overlapping relationship with the display screen, and arranged to transmit an acoustic signal from substantially all of its surface;

a receiver arranged to receive a reflection of the acoustic signal from an object which is directly in front of the display screen; and

means for characterising the shape, location or motion of the object using information determined from the received signal.

51. Apparatus as claimed in claim 50 wherein the transmitting surface is also a receiving surface, and the receiver is arranged to receive the reflection of the signal at the receiving surface.

52. Apparatus as claimed in claim 50 or 51 comprising a plurality of receivers separate from the transmitting surface, each arranged to receive a reflection of the acoustic signal from an object which is directly in front of the display screen.

53. Apparatus as claimed in any of claims 50 to 52 wherein the transmitting surface is flat.

54. Apparatus as claimed in any of claims 50 to 53 wherein the transmitting surface is configured to receive a touch input.

55. Apparatus as claimed in any of claims 50 to 54 wherein all of the display screen acts as a transmitter.

56. Apparatus as claimed in any of claims 50 to 54 wherein the transmitting surface is disposed in front of the display screen.

57. Apparatus as claimed in any of claims 50 to 56 wherein at least an area of the transmitting surface is optically transparent.

58. Apparatus as claimed in any of claims 50 to 57 wherein the display screen and/or transmitting surface is planar.

59. Apparatus as claimed in any of claims 50 to 58 wherein the transmitting surface is arranged to transmit an acoustic signal when an electric potential is applied across it.

60. Apparatus as claimed in any of claims 50 to 59 wherein the transmitting surface is arranged to transmit an acoustic signal when a varying electric or magnetic field surrounds the surface.

61. Apparatus as claimed in any of claims 50 to 60 comprising an actuator coupled to the transmitting surface and arranged to displace the transmitting surface as a whole.

62. Apparatus as claimed in any of claims 50 to 61 comprising an energising transmitter, arranged to direct acoustic energy through air towards the transmitting surface.

63. Apparatus as claimed in claim 62 wherein the energising transmitter is located at least partially on the opposite side of the transmitting surface to the object.

64. Apparatus as claimed in claim 62 or 63 wherein the energising transmitter is configured to induce Lamb waves within the transmitting surface.

65. Apparatus as claimed in any of claims 62 to 64 comprising means to focus acoustic energy from the energising transmitter on a particular region of the transmitting surface.

66. Apparatus as claimed in claim 65 configured to control the energising transmitters so as to cause the acoustic signal to be transmitted directionally from the transmitting surface.

67. Apparatus claimed in any of claims 50 to 61 comprising a plurality of actuators coupled to the transmitting surface, each actuator being arranged to generate surface acoustic waves in the transmitting surface.

68. Apparatus as claimed in claim 67 configured to control the actuator so as to cause the surface acoustic waves to interfere in such a way that acoustic energy is transmitted directionally from the transmitting surface.

69. Apparatus as claimed in claim 67 or 68 configured to control the actuator so as to cause the surface acoustic waves to interfere in such a way that acoustic energy is transmitted primarily from a particular point on the transmitting surface.

70. Apparatus as claimed in any of claims 50 to 69 comprising control means configured to transmit sound more strongly from a point relatively close to the object than from another point on the transmitting surface which is relatively removed from the object.

71. Apparatus as claimed in any of claims 50 to 70 comprising control means configured to direct a beam of sound towards the object.

72. Apparatus as claimed in any of claims 50 to 71 wherein the acoustic signal comprises one or more pulses.

73. A method of characterising the shape, location or motion of an object, comprising:

transmitting an acoustic signal from a transmitting surface, the transmitting surface comprising a display screen or being disposed in substantially overlapping relationship with a display screen;

receiving a reflection of the signal from an object which is directly in front of the display screen; and

characterising the shape, location or motion of the object using information determined from the received signal.

74. A method as claimed in claim 73 wherein the transmitting surface is also a receiving surface, comprising receiving the reflection of the signal at the receiving surface to generate a received signal.

75. A method as claimed in claim 73 or 74 wherein the object is all or part of a human hand.

76. A method as claimed in any of claims 73 to 75 further comprising characterising the motion of the object when the object is located beyond the region defined by a projection of the display screen.

77. A method as claimed in any of claims 73 to 76 comprising using an energising transmitter to direct acoustic energy through air towards the transmitting surface.

78. A method as claimed in claim 77 comprising controlling the energising transmitters so as to cause the acoustic signal to be transmitted directionally from the transmitting surface.

79. A method as claimed in any of claims 73 to 76 comprising using a plurality of actuators coupled to the transmitting surface to generate surface acoustic waves in the transmitting surface.

80. A method as claimed in claim 79 comprising controlling the actuators so as to cause the surface acoustic waves to interfere in such a way that acoustic energy is transmitted directionally from the transmitting surface.

81. A method as claimed in claim 79 or 80 comprising controlling the actuators so as to cause the surface acoustic waves to interfere in such a way that acoustic energy is transmitted primarily from a particular point on the transmitting surface.

82. A method as claimed in any of claims 73 to 80 comprising transmitting acoustic pulses from the transmitting surface.