Earphone with noise reduction having a modified port

• US 20170195776A1
• Filed: 12/20/2016
• Published: 07/06/2017
• Est. Priority Date: 12/30/2015
• Status: Abandoned Application

• Current Assignee: Gn Audio A/S (GN Store Nord A/S)
• Original Assignee: Gn Audio A/S (GN Store Nord A/S)
• Inventors: REIMERT, Jacob
• Application Number:
  US15/384,424
• Publication Number:
  US 20170195776A1
• Time in Patent Office: Days
• CPC Class Codes: G10K 11/17861 using additional means for damping sound, e.g. using sound absorbing panels
• CPC Class Codes: G10K 11/17879 using both a reference signal and an error signal
• 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: H04R 1/1008 Earpieces of the supra-aural or circum-aural type
• 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 1/22 for obtaining desired frequency characteristic only circuit for combining transducers having different responses H04R3/00; for hearing aids H04R25/407
• CPC Class Codes: H04R 1/2823 Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material number or position of ports H04R1/2815; vents in bandpass type enclosures H04R1/2846
• CPC Class Codes: H04R 1/2826 for loudspeaker transducers
• CPC Class Codes: H04R 1/2846 Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material number or position of ports H04R1/2838; vents in bass reflex type enclosures H04R1/2823
• CPC Class Codes: H04R 5/033 Headphones for stereophonic communication details thereof, e.g. relating to batteries, cables or control elements H04R1/10

Abstract

An earphone is provided, the earphone being configured to provide an acoustic output signal to an ear of a wearer in dependence on an earphone audio signal and further configured to be arranged on the wearer'"'"'s head in an operating position such that a front cavity between the head and the earphone is separated from ambient space. The earphone comprises a housing having a housing wall separating a rear cavity from the front cavity and from ambient space, an ear cushion, a first diaphragm suspended across an opening in the housing wall between the front cavity and the rear cavity and configured to be actively driven. The earphone further has a port structure fluidly connecting the rear cavity and ambient space through the housing wall. The port structure having a first open end fluidly coupled to the rear cavity and a second open end fluidly coupled to ambient space, and having a port cavity defined by the first open end, the second open end and a port wall, the port wall extending from the housing wall into the rear cavity and/or into the ambient space. The port wall has one or more acoustically permeable sections fluidly connecting the port cavity with the rear cavity and/or the ambient space through the port wall.

Claims

1. An earphone configured to provide an acoustic output signal to an ear of a wearer in dependence on an earphone audio signal and further configured to be arranged on the wearer'"'"'s head in an operating position such that a front cavity between the head and the earphone is separated from ambient space, the earphone comprising:

a housing having a housing wall separating a rear cavity from the front cavity and from ambient space;

an ear cushion arranged and configured to attenuate acoustic signals entering the front cavity from ambient space when the earphone is in the operating position;

a first diaphragm suspended across an opening in the housing wall between the front cavity and the rear cavity and configured to be actively driven to provide at least a portion of the acoustic output signal;

a port structure fluidly connecting the rear cavity and ambient space through the housing wall, the port structure having a first open end fluidly coupled to the rear cavity and a second open end fluidly coupled to ambient space, and the port structure having a port cavity defined by the first open end, the second open end and a port wall, the port wall extending from the housing wall into the rear cavity and/or into the ambient space, wherein the port wall has one or more acoustically permeable sections fluidly connecting the port cavity with the rear cavity and/or the ambient space through the port wall.

2. An earphone according to claim 1, wherein the port structure fluidly connecting the rear cavity and ambient space has a port structure resonance frequency, and wherein the port structure resonance frequency is between 100 Hz and 1 kHz, such as between 100 Hz and 500 Hz.

3. An earphone according to claim 1, wherein the port structure and the rear cavity are configured to act as a second order low pass filter.

4. An earphone according to claim 1, wherein the port structure is configured to act as an acoustically open hole between the rear cavity and ambient space at low frequencies.

5. An earphone according to claim 1, wherein the one or more acoustically permeable sections are distributed along a length of the port wall, or wherein the one or more acoustically permeable sections are distributed at different distances from the housing wall.

6. An earphone according to claim 1, wherein the port wall has a port wall area, and wherein the one or more acoustically permeable sections are distributed over between 5% and 50% of the port wall area.

7. An earphone according to claim 1, wherein the one or more acoustically permeable sections comprises through holes, acoustically resistive openings, through holes covered with an acoustical lossy material, through holes covered with an acoustical mesh.

8. An earphone according to claim 1, wherein the acoustic impedance of the one or more acoustically permeable sections is between 500 and 8000 L/m²s.

9. An earphone according to claim 1, wherein the one or more acoustically permeable sections are distributed discretely along the length of the port wall

10. An earphone according to claim 1 any of the procoding claims, wherein the port structure has a longitudinal extension in a longitudinal direction non-parallel with the housing wall which is larger than a transversal extension in a direction parallel to the housing wall.

11. An earphone according to claim 1, wherein the port structure comprises a tubular member having a first open end fluidly coupled to the rear cavity and a second open end fluidly coupled to ambient space, the tubular member having a tubular member wall defining the port cavity, and wherein the tubular member has a base and a height, the base having a circumscribed circle or the base being circular, wherein the height relative to a diameter of the circumscribed circle or of the circular base is larger than one.

12. An earphone according to claim 1, wherein the one or more acoustically permeable sections are dimensioned to dampen the resonance of the port structure by at least 6 dB.

13. An earphone according to claim 1, wherein at least one acoustically permeable section is a longitudinal section having a length corresponding to at least 80% of a length of the port wall, or wherein at least one acoustically permeable section is a circumferential section extending along at least 80% of a circumference of the port wall, and/or wherein a width of the longitudinal section and/or a width of the circumferential section corresponds to less than 25% of the length of the port wall.

14. An earphone according to claim 1, the earphone further comprising a noise cancelling circuit being configured to receive the earphone audio signal, to implement an active noise cancelling function and to provide a noise cancelling audio signal to the ear of a wearer.

15. A hearing device comprising one or two earphones according to claim 1 and configured to provide an earphone audio signal to each of the one or two earphones in dependence on one or more audio input signals.