BONE-CONDUCTION PICKUP TRANSDUCER FOR MICROPHONIC APPLICATIONS

• US 20140072148A1
• Filed: 05/15/2013
• Published: 03/13/2014
• Est. Priority Date: 09/10/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Yang, Henry H., Andersen, Esge B., Dusan, Sorin V., Kanaris, Alexander, Smith, Wesley S., Last, Matthew E.
• Granted Patent: US 8,983,096 B2
• Time in Patent Office: Days
• US Class Current: 381/151
• CPC Class Codes: H04R 1/08 Mouthpieces; Microphones; Attachments therefor
• CPC Class Codes: H04R 1/083 Special constructions of mouthpieces
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 1/46 Special adaptations for use as contact microphones, e.g. on musical instrument, on stethoscope throat mountings H04R1/14
• CPC Class Codes: H04R 2460/13 Hearing devices using bone conduction transducers

Abstract

A personal audio device has a bone conduction pickup transducer, having a housing of which a rigid outer wall has an opening formed therein. A volume of yielding material fills the opening in the rigid outer wall. An electronic vibration sensing element is embedded in the volume of yielding material. The housing is shaped, and the opening is located, so that the volume of yielding material comes into contact with an ear or cheek of a user who is using the personal audio device. Other embodiments are also described and claimed.

Claims

1. A personal audio device comprising:

a bone conduction pickup transducer having

a housing of which a rigid outer wall has an opening formed therein;

a volume of yielding material that fills the opening in the rigid outer wall; and

an electronic vibration sensing element embedded in the volume of yielding material, wherein the housing is shaped, and the opening is located, so that the volume of yielding material comes into contact with an ear or cheek of a user who is using the personal audio device.

2. The device of claim 1 wherein the housing is an in-ear earphone housing in which the vibration sensing element and the volume of yielding material are held, the device further comprising a sound emitting transducer held inside the housing.

3. The device of claim 2 further comprising an electronics accessory cable that is coupled to the vibration sensing element to transfer a vibration signal to an audio source device, and is coupled to the sound emitting transducer to deliver an audio signal from the audio source device.

4. The device of claim 1 wherein the housing is a mobile phone handset housing in which the vibration sensing element and the volume of yielding material are held, the device further comprising a sound emitting transducer held inside the housing.

5. The device of claim 1 wherein the volume of yielding material comprises two sections of different material, one of which extends inward of the housing wall and another lies outward of the housing wall.

6. The device of claim 5 wherein one of the two sections of the volume of yielding material is made of a material that enhances mechanical vibration coupling to the user'"'"'s ear or cheek, while another is made of a material that absorbs or reflects sound waves coming through the air and vibrations coming through the housing wall.

7. The device of claim 2 further comprising an acoustically isolating suspension for mounting the sound emitting transducer to the inside of the housing.

8. A personal audio device comprising:

a headset having a headset housing and a bone conduction pickup transducer, the bone conduction pickup transducer comprising a volume of yielding material that fills an opening formed in a rigid outer wall of the headset housing, and an electronic vibration sensing element embedded in the volume of yielding material, wherein the headset housing is shaped, and the opening is located, so that the volume of yielding material comes into contact with an ear of a user who is wearing the headset.

9. The personal audio device of claim 8 further comprising an accessory cable connected at one end to the headset housing, wherein the cable is to be connected at another end to a host audio device.

10. The personal audio device of claim 8 wherein the headset housing is that of an earbud type earphone.

11. The personal audio device of claim 8 wherein the electronic vibration sensing element comprises a MEMS spring-damper system whose resonance frequency lies outside an operating range of the bone conduction pickup transducer.

12. The personal audio device of claim 11 wherein the resonance frequency is higher than 3 kHz.

13. The personal audio device of claim 8 wherein the volume of yielding material comprises two sections of different material, one of which extends inward of the housing wall and another that extends outward of the housing wall.

14. The personal audio device of claim 13 wherein one of the two sections of the volume of yielding material is made of a material that enhances mechanical vibration coupling to the user'"'"'s ear, while another is made of a material that absorbs or reflects sound waves coming through the air and vibrations coming through the housing wall.

15. The personal audio device of claim 8 further comprising:

a sound emitting transducer held inside the headset housing; and

an acoustically isolating suspension for mounting the sound emitting transducer to the inside of the housing.

16. A personal audio device comprising:

a bone conduction audio pickup transducer having a housing of which a rigid outer wall has an opening formed therein, a volume of yielding material fills the opening in the rigid outer wall, and an electronic vibration sensing element embedded in the volume of yielding material, wherein the housing is shaped, and the opening is located, so that the volume of yielding material comes into contact with an ear canal wall of a user who is using the personal audio device, and the yielding material can decouple vibrations through the housing wall while enhancing coupling of vibrations through the ear canal wall.

17. The personal audio device of claim 16 wherein the yielding material has a human flesh-like or human tissue like hardness and texture that to better impedance match with the ear canal wall.

18. The personal audio device of claim 17 wherein the yielding material has a hardness score of less than 10 Shore A.

19. The personal audio device of claim 18 wherein the yielding material has a hardness score of less than 20 Shore 00.

20. The personal audio device of claim 16 wherein the yielding material has a hardness score of less than 10 Shore A.