User Interface for ANR Headphones with Active Hear-Through

• US 20140126733A1
• Filed: 11/02/2012
• Published: 05/08/2014
• Est. Priority Date: 11/02/2012
• Status: Abandoned Application

• Current Assignee: Bose Corporation
• Original Assignee: Daniel M. Gauger Jr
• Inventors: Gauger, Daniel M. Jr., Hill, Misha K.
• Application Number:
  US13/667,092
• Publication Number:
  US 20140126733A1
• Time in Patent Office: Days
• US Class Current: 381/71.6
• CPC Class Codes: G06F 3/165 Management of the audio stream, e.g. setting of volume, audio stream path
• CPC Class Codes: G10K 11/17821 characterised by the analysis of the input signals only
• CPC Class Codes: G10K 11/17823 Reference signals, e.g. ambient acoustic environment
• CPC Class Codes: G10K 11/1783 handling or detecting of non-standard events or conditions, e.g. changing operating modes under specific operating conditions
• CPC Class Codes: G10K 11/17835 using detection of abnormal input signals
• CPC Class Codes: G10K 11/17837 by retaining part of the ambient acoustic environment, e.g. speech or alarm signals that the user needs to hear
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17861 using additional means for damping sound, e.g. using sound absorbing panels
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 11/17885 additionally using a desired external signal, e.g. pass-through audio such as music or speech
• CPC Class Codes: G10K 2210/1081 Earphones, e.g. for telephones, ear protectors or headsets
• CPC Class Codes: G10K 2210/3026 Feedback
• CPC Class Codes: G10K 2210/3027 Feedforward
• CPC Class Codes: G10K 2210/3055 Transfer function of the acoustic system
• CPC Class Codes: G10K 2210/3056 Variable gain
• CPC Class Codes: H04R 1/1041 Mechanical or electronic switches, or control elements switches in general H01H
• 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 2460/01 Hearing devices using active noise cancellation

Abstract

An active noise reducing headphone has an active noise-cancelling mode and an active hear-through mode, and changes between the noise-cancelling mode and the hear-through mode based on detection of a user touching a housing of the headphone or based on a command signal received from an external device. In another aspect, a signal processor in the headphone is configured to change between the active noise-cancelling and active hear-through modes based on a comparison of signals from a feed-forward microphone and a feedback microphone. During the hear-through mode, the signal processor detects high-frequency signals in the feed-forward path exceeding a threshold level indicative of abnormally high acoustic coupling of the output transducer to the feed-forward microphone, and applies a compressing limiter to the feed-forward path until the high-frequency signals are no longer detected at levels above the threshold.

Claims

1. An active noise reducing headphone having an active noise-cancelling mode and an active hear-through mode, wherein the headphone changes between the active noise-cancelling mode and the active hear-through mode based on detection of a user touching a housing of the headphone.

2. An active noise reducing headphone having an active noise-cancelling mode and an active hear-through mode, wherein the headphone changes between the active noise-cancelling mode and the active hear-through mode based on a command signal received from an external device.

3. The headphone of claim 2, further comprising an optical detector for receiving the command signal.

4. The headphone of claim 2, further comprising a radio-frequency receiver for receiving the command signal.

5. The headphone of claim 2, wherein the command signal comprises an audio signal.

6. The headphone of claim 5, wherein the headphone is configured to receive the command signal through a microphone integrated into the headphone.

7. The headphone of claim 5, wherein the headphone is configured to receive the command signal through a signal input of the headphone for receiving an input electronic audio signal.

8. An active noise reducing headphone comprising:

an ear piece configured to couple to a wearer'"'"'s ear to define an acoustic volume comprising the volume of air within the wearer'"'"'s ear canal and a volume within the ear piece;

a feed-forward microphone acoustically coupled to an external environment and electrically coupled to a feed-forward active noise cancellation signal path;

a feedback microphone acoustically coupled to the acoustic volume and electrically coupled to a feedback active noise cancellation signal path;

an output transducer acoustically coupled to the acoustic volume via the volume within the ear piece and electrically coupled both to the feed-forward and feedback active noise cancellation signal paths; and

a signal processor configured to apply filters and control gains of both the feed-forward and feedback active noise cancellation signal paths;

wherein the signal processor is configured to;

operate the headphone in a first operating mode providing effective cancellation of ambient sound and in a second operating mode providing active hear-through of ambient sounds, and

change between the first and second operating modes based on a comparison of signals from the feed-forward microphone and the feedback microphone.

9. The headphone of claim 8 wherein the signal processor is configured to change from the first operating mode to the second operating mode when the comparison of signals from the feed-forward microphone and the feedback microphone indicates that the user of the headphone is speaking.

10. The headphone of claim 9 wherein the signal processor is further configured to change from the second operating mode to the first operating mode a pre-determined amount of time after the comparison of signals from the feed-forward microphone and the feedback microphone no longer indicates that the user of the headphone is speaking.

11. The headphone of claim 8 wherein the signal processor is configured to change from the first operating mode to the second operating mode when signals from the feedback microphone are correlated with the signals from the feed-forward microphone within a frequency band consistent with the portion of human speech amplified by the occlusion effect and are above a threshold level indicative of the user speaking.

12. An active noise reducing headphone having an active noise-cancelling mode and an active hear-through mode, the headphone comprising:

an indicator activated when the headphone is in the active hear-through mode,

the indicator visible over a limited viewing angle viewable only from in front of the headphone.

13. An active noise reducing headphone comprising:

an ear piece configured to couple to a wearer'"'"'s ear to define an acoustic volume comprising the volume of air within the wearer'"'"'s ear canal and a volume within the ear piece;

a feed-forward microphone acoustically coupled to an external environment and electrically coupled to a feed-forward active noise cancellation signal path;

a feedback microphone acoustically coupled to the acoustic volume and electrically coupled to a feedback active noise cancellation signal path;

an output transducer acoustically coupled to the acoustic volume via the volume within the ear piece and electrically coupled both to the feed-forward and feedback active noise cancellation signal paths; and

a signal processor configured to apply filters and control gains of both the feed-forward and feedback active noise cancellation signal paths;

wherein the signal processor is configured to;

operate the headphone in a first operating mode providing effective cancellation of ambient sound and in a second operating mode providing active hear-through of ambient sounds,

during the second operating mode, detect high-frequency signals in the feed-forward active noise cancellation signal path exceeding a threshold level indicative of abnormally high acoustic coupling of the output transducer to the feed-forward microphone,

in response to the detection, apply a compressing limiter to the feed-forward signal path, and

once the high-frequency signals are no longer detected at levels above the threshold, remove the compressing limiter from the feed-forward signal path.