Balanced armature devices and methods for hearing

• US 8,858,419 B2
• Filed: 03/22/2011
• Issued: 10/14/2014
• Est. Priority Date: 09/22/2008
• Status: Active Grant

• Current Assignee: EarLens Corporation
• Original Assignee: EarLens Corporation
• Inventors: Puria, Sunil, Rosen, Micha, Fay, Jonathan P., Rucker, Paul, Stone, James
• Primary Examiner(s): Cheng, Jacqueline
• Assistant Examiner(s): FOLEY, EILEEN DOROTHY
• Application Number:
  US13/069,262
• Publication Number:
  US 20120014546A1
• Time in Patent Office: 1,302 Days
• Field of Search: 600/25, 381/312, 381/320, 381/328, 607 55- 57
• US Class Current: 600/25
• CPC Class Codes: H04R 11/02 Loudspeakers
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00
• CPC Class Codes: H04R 2225/025 In the ear hearing aids [ITE] hearing aids
• CPC Class Codes: H04R 23/008 using optical signals for detecting or generating sound
• CPC Class Codes: H04R 2460/09 Non-occlusive ear tips, i.e. leaving the ear canal open, for both custom and non-custom tips H04R2460/11 takes precedence
• CPC Class Codes: H04R 2460/13 Hearing devices using bone conduction transducers
• CPC Class Codes: H04R 25/02 adapted to be supported entirely by ear
• CPC Class Codes: H04R 25/554 using a wireless connection, e.g. between microphone and amplifier or using Tcoils
• CPC Class Codes: H04R 25/606 acting directly on the eardrum, the ossicles or the skull, e.g. mastoid, tooth, maxillary or mandibular bone, or mechanically stimulating the cochlea, e.g. at the oval window
• CPC Class Codes: H04R 25/65 Housing parts, e.g. shells, tips or moulds, or their manufacture
• CPC Class Codes: H04R 25/652 Ear tips; Ear moulds hybrid ear moulds or post-processing thereof for their customisation H04R25/659

Abstract

A device to transmit an audio signal to a user comprises a transducer and a support. The support is configured for placement on the eardrum to drive the eardrum. The transducer is coupled to the support at a first outer location to decrease occlusion and a second inner location to drive the eardrum. The transducer may comprise one or more of an electromagnetic balanced armature transducer, a piezoelectric transducer, a magnetostrictive transducer, a photostrictive transducer, or a coil and magnet. The device may find use with open canal hearing aids.

Claims

1. A device to transmit an audio signal to a user, the user having an ear comprising an eardrum, the device comprising:

a transducer; and

a support configured for placement at least partially against an outer portion of the eardrum without penetrating the outer portion, the transducer coupled to the support at a first location and a second location to drive the eardrum when the support is placed at least partially against the eardrum, wherein the first location of the support is configured to be placed over a first eardrum portion and the second location of the support is configured to be placed over a second eardrum portion,

wherein the first location of the support is configured to align with at least a portion of the malleus of the ear and wherein the second location of the support is configured to align with a location away from the first location such that the first location is separated from the second location by distance of at least 1 mm,

wherein the transducer is coupled to the support to support the transducer at the first location and the second location, and

wherein the transducer comprises an input element and a movable structure coupled to the support at the first location and configured to drive the eardrum at the first location in response to movement of the movable structure.

2. The device of claim 1 wherein the first location of the support is configured to align with an umbo of the ear when the support is placed on the eardrum.

3. The device of claim 1 wherein the second location of the support is configured to align with at least one of a lateral process of the malleus or a bony part of the external ear canal when the support is placed on the eardrum.

4. The device of claim 3 wherein the second location of the support is configured to align with the lateral process of the malleus and wherein the transducer comprises an elongate dimension extending between the first location and the second location and wherein the elongate dimension of the transducer is within a range from about 2 mm to about 5 mm.

5. The device of claim 3 wherein the second location of the support is configured to align with a location of the eardrum away from the lateral process of the malleus to decrease interference from blood flow when the support is placed on the eardrum and wherein the transducer comprises an elongate dimension extending between the first location and the second location and wherein the elongate dimension of the transducer is within a range from about 2 mm to about 5 mm.

6. The device of claim 1 wherein the transducer comprises a center of mass and wherein the transducer is positioned on the support such that the center of mass of the transducer is configured to align with a location along the eardrum away from the umbo when the support is placed on the eardrum.

7. The device of claim 6 wherein the transducer extends between the first location and the second location toward a bony part of the ear canal when the support is placed on the eardrum.

8. The device of claim 1 wherein the support is shaped to the eardrum of the user to align the transducer with the eardrum in a pre-determined orientation.

9. The device of claim 8 wherein a fluid is disposed between the eardrum and the support to couple the support with the eardrum.

10. The device of claim 8 wherein the transducer is positioned on the support to align an elongate dimension of the transducer with the malleus of the user when the support is placed on the eardrum.

11. The device of claim 8 wherein the transducer comprises an elongate structure configured to move in response to the audio signal and wherein the elongate structure is positioned on the support to align with a handle of the malleus of the user when the support is placed on the eardrum.

12. The device of claim 8 wherein the support corresponds to a shape of the eardrum of the user to couple the support to the eardrum with the predetermined orientation.

13. The device of claim 12 wherein the support comprises a shape from a mold of the eardrum of the user.

14. The device of claim 8 wherein the transducer is positioned on the support such that an elongate dimension of the transducer extends along a handle of the malleus when the support is placed on the eardrum of the user.

15. The device of claim 8 wherein the transducer is positioned on the support to align the transducer with the lateral process of the malleus when the support is placed on the eardrum.

16. The device of claim 1 wherein the transducer comprises at least one of an electromagnetic balanced armature transducer, a piezoelectric transducer, a magnetostrictive transducer, a photostrictive transducer, an electrostatic transducer, a coil or a magnet.

17. The device of claim 16 wherein the transducer comprises the electromagnetic balanced armature transducer and wherein the balanced armature transducer comprises an armature configured to move in response to a magnetic field and wherein armature is positioned on the support and the coupled to the first location to balance the armature when the support is placed on the eardrum of the user.

18. The device of claim 17 further comprising an extension structure coupled to the armature and the first location and wherein the extension structure extends from the armature to the first location along a distance within a range from about 0.5 mm to about 2.0 mm to balance the armature when the support is placed on the eardrum.

19. The device of claim 18 wherein extension structure comprises at least one of a substantially non-flexible structure or a tuning structure.

20. The device of claim 18 wherein at least one of the extension structure or the first attachment structure comprises a conformable material to decrease static loading of the transducer and occlusion when the transducer is coupled to the eardrum with the support.

21. The device of claim 20 wherein the conformable material comprises one or more of an elastic material, a viscous material, or a viscoelastic material.

22. The device of claim 17 wherein the armature extends along a first dimension and wherein the at least one of the extension structure extends along a second dimension offset from the first dimension.

23. The device of claim 17 wherein the armature has at least one of a mass, a damping, or a stiffness and wherein the at least one of mass, the damping, or the stiffness are configured to match a mass and a stiffness of the support and the eardrum when the support is placed on the eardrum.

24. The device of claim 17 wherein the balanced armature transducer is adapted to drive the support when the support is coupled to the eardrum.

25. The device of claim 24 wherein the balanced armature transducer is adapted to drive the support with optimization of at least one of an output mechanical impedance of the armature matched to an input impedance of the support, a size of the balanced armature transducer, a length of the balanced armature transducer, an electrical impedance of the balanced armature transducer, materials from which the balanced armature transducer is made, a spring constant of a restoring member coupled to the armature of the balanced armature transducer to restore the armature to a neutral position, a number of turns of a wire of a coil wrapped around the armature of the balanced armature transducer, a moment of inertia of the balanced armature, a countermass on the balanced armature opposite the support to balance a mechanical load of the support, or a diameter of the wire of the coil wrapped around the armature of the balanced armature transducer.

26. The device of claim 1 wherein the transducer and the support are configured to provide a sound output of at least 80 dB (SPL) with no more than 5% distortion at 10 kHz and no more than about 1 mW of electrical power input to the transducer.

27. The device of claim 26 wherein the transducer and the support are configured to provide the sound output of at least 80 dB (SPL) and no more than 5% distortion over a range from about 100 Hz to about 10 kHz with the no more than about 1 mW of electrical power input to the transducer.

28. The device of claim 1 further comprising:

a casing affixed to the body of the transducer;

circuitry coupled to the transducer to drive the transducer, the circuitry supported with the support when the support is placed on the eardrum;

wherein the support, the casing, the transducer and the circuitry comprise a combined mass of no more than about 120 mg and wherein the transducer is positioned on the support such that the combined mass when the support is positioned on the eardrum corresponds to a mass of no more than about 60 mg at the umbo.

29. The device of claim 28 wherein the support, the casing the circuitry, and the transducer comprise a combined mass of no more than about 80 mg and wherein the transducer is positioned on the support such that the combined mass when the support is positioned on the eardrum corresponds to a mass of no more than about 40 mg at the umbo.

30. The device of claim 1 wherein the transducer is electrically coupled to at least one of a coil, an electrical connection, an output amplifier or a sound processor.

31. The device of claim 1 wherein the first eardrum portion comprises one or more of an outer portion of the eardrum inside an annulus of the eardrum or at least a portion of the annulus of the eardrum.

32. The device of claim 31 wherein the second eardrum portion comprises the umbo of the eardrum.

33. The device of claim 1, wherein the support comprises an outer component configured to contact the eardrum.

34. The device of claim 33, wherein the outer component of the support is configured to align with one or more of an outer portion of the eardrum inside an annulus of the eardrum or at least a portion of the annulus of the eardrum.

35. The device of claim 34, wherein the outer component of the support is one or more of annular, O-shaped, or C-shaped.

36. The device of claim 33, wherein at least a portion of the outer component of the support is shaped to conform to at least a portion of one or more of an outer portion of the eardrum inside an annulus of the eardrum and at least a portion of the annulus of the eardrum.

37. The device of claim 33, wherein the first location is positioned on the outer component of the support.

38. The device of claim 33, wherein the support comprises an inner component within the outer component of the support, the inner component configured to contact the eardrum.

39. The device of claim 38, wherein the second location is positioned on the inner component of the support.

40. A device to transmit an audio signal to a user, the user having an ear comprising an eardrum, the device comprising:

a transducer; and

a support configured for placement at least partially against an outer portion of the eardrum without penetrating the outer portion, the transducer coupled to the support at a first location and a second location to drive the eardrum when the support is placed at least partially against the eardrum, wherein the first location of the support is configured to be placed over a first eardrum portion and the second location of the support is configured to be placed over a second eardrum portion,

wherein the first location of the support is configured to align with at least a portion of the malleus of the ear and wherein the second location of the support is configured to align with a location away from the first location such that the first location is separated from the second location by distance of at least 1 mm, and

wherein the second location of the support is configured to align with corresponds to the bony part of the external ear canal and wherein the transducer comprises an elongate dimension extending between the first location and the second location and wherein the elongate dimension of the transducer is within a range from about 4 mm to about 10 mm.

41. The device of claim 40 wherein the second location of the support is configured to align with a portion of the bony part of the external ear canal located away from the malleus to decrease interference from blood flowing along the malleus to the eardrum.

42. A device to transmit an audio signal to a user, the user having an ear comprising an eardrum, the device comprising:

a transducer; and

a support configured for placement at least partially against an outer portion of the eardrum without penetrating the outer portion, the transducer coupled to the support at a first location and a second location to drive the eardrum when the support is placed at least partially against the eardrum, wherein the first location of the support is configured to be placed over a first eardrum portion and the second location of the support is configured to be placed over a second eardrum portion,

wherein the first location of the support is configured to align with at least a portion of the malleus of the ear and wherein the second location of the support is configured to align with a location away from the first location such that the first location is separated from the second location by distance of at least 1 mm, and

wherein a second movement at the second location is less than a first movement at the first location when the transducer drives the eardrum.

43. The device of claim 42 the second movement at the second location is no more than about 75% of the first movement of the first location when the transducer drives the eardrum.

44. A device to transmit an audio signal to a user, the user having an ear comprising an eardrum, the device comprising:

a transducer; and

a support configured for placement at least partially against an outer portion of the eardrum without penetrating the outer portion, the transducer coupled to the support at a first location and a second location to drive the eardrum when the support is placed at least partially against the eardrum, wherein the first location of the support is configured to be placed over a first eardrum portion and the second location of the support is configured to be placed over a second eardrum portion,

wherein the first location of the support is configured to align with at least a portion of the malleus of the ear and wherein the second location of the support is configured to align with a location away from the first location such that the first location is separated from the second location by distance of at least 1 mm, and

further comprising a first attachment structure affixed to the support at the first location and wherein the first attachment structure is coupled to an elongate movable structure of the transducer.

45. The device of claim 44 wherein the first attachment structure is embedded in the support.

46. The device of claim 44 wherein the first attachment structure is affixed to the elongate movable structure.

47. The device of claim 44 wherein the elongate movable structure comprises at least one of a reed or an armature configured to move in response to the audio signal and wherein an extension structure extends from the elongate movable structure to the first attachment structure to couple the elongate movable structure to the first attachment structure.

48. The device of claim 47 wherein the elongate movable structure extends along a first elongate dimension and the extension structure extends along a second elongate dimension transverse to the first dimension.

49. The device of claim 47 wherein the extension structure comprises at least one of a tuning structure or a structure that does not flex substantially when the ear is driven.

50. The device of claim 49 wherein the extension structure comprises the tuning structure to tune a gain of the transducer in response to frequencies and wherein the tuning structure is coupled to the support at the first location.

51. The device of claim 49 wherein the extension structure comprises the structure that does not flex substantially when the ear is driven and wherein the extension structure comprises a rod composed of surgical grade stainless steel configured such that the rod does not flex substantially when the ear is driven.

52. The device of claim 47 wherein at least one of the extension structure or the first attachment structure comprises a conformable material to decrease static loading of the transducer and occlusion when the transducer is coupled to the eardrum with the support.

53. The device of claim 52 wherein the conformable material comprises one or more of a viscoelastic material or a viscous liquid.

54. The device of claim 44 further comprising a second attachment structure affixed to the support at a second location and wherein the second attachment structure is coupled to the transducer away from the elongate movable structure.

55. The device of claim 44 wherein the first attachment structure comprises at least one of a plate, a coil, a dome, a tripod, or a cone embedded in the support at the first location.

56. The device of claim 44 wherein the first attachment structure comprises a maximum dimension across of no more than about 3 mm.

57. A device to transmit an audio signal to a user, the user having an ear comprising an eardrum, the device comprising:

a transducer; and

a support configured for placement at least partially against an outer portion of the eardrum without penetrating the outer portion, the transducer coupled to the support at a first location and a second location to drive the eardrum when the support is placed at least partially against the eardrum, wherein the first location of the support is configured to be placed over a first eardrum portion and the second location of the support is configured to be placed over a second eardrum portion,

further comprising;

at least one photodetector coupled to the transducer, the at least one photodetector comprising an output impedance and wherein the transducer comprises a balanced armature transducer comprising an input impedance and wherein the output impedance of the photodetector matches the input impedance of the balanced armature transducer.

58. The device of claim 57 wherein the at least one photodetector comprises a photovoltaic transducer.