Magnetic-resonance compatible earphone, magnetic-resonance compatible intercom system and head coil apparatus

1 . A magnetic-resonance imaging system compatible earphone, comprising:

an earphone body;

a diaphragm disposed on the earphone body;

a drive coil disposed on the earphone body, the drive coil being configured to receive audio current;

an elastic sheet disposed on the earphone body, the drive coil being fixed to the elastic sheet; and

a transmission member connecting the elastic sheet and the diaphragm,

wherein upon receiving the audio current, the drive coil is configured to generate a Lorentz force in response to a main magnetic field that is generated via a magnetic resonance imaging system,

wherein the drive coil is configured to cause, via the Lorentz force generated by the drive coil, the elastic sheet to elastically deform to induce movement in the transmission member, and

wherein the movement of the transmission member drives the diaphragm to thereby generate sound via vibration.

2 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein:

the elastic sheet is arranged perpendicular to an output direction of the magnetic-resonance imaging system compatible earphone,

an edge of the elastic sheet is fixed to the earphone body,

the elastic sheet comprises a connecting portion that is configured to move in a direction parallel to the output direction as the elastic sheet deforms, and

the transmission member extends in the output direction, having one end connected to the connecting portion and another end connected to the diaphragm.

3 . The magnetic-resonance imaging system compatible earphone as claimed in claim 2 , wherein:

the drive coil comprises an annular winding that is wound along a plane perpendicular to the output direction,

one end of the annular winding is fixed to the connecting portion,

the annular winding extends toward an edge of the elastic sheet in a direction parallel to a predetermined magnetic field direction, and

the predetermined magnetic field direction is perpendicular to the output direction.

4 . The magnetic-resonance imaging system compatible earphone as claimed in claim 3 , wherein:

the drive coil comprises a pair of annular windings,

the pair of annular windings are arranged symmetrically across a plane that is perpendicular to the predetermined magnetic field direction, and

audio currents flow in opposite directions in each respective winding of the pair of annular windings.

5 . The magnetic-resonance imaging system compatible earphone as claimed in claim 4 , wherein the pair of annular windings is formed by continuously winding a length of conductive wire.

6 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the diaphragm and the drive coil are integrated as a flexible circuit board.

7 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the drive coil is configured to drive the diaphragm to vibrate via the Lorentz force generated by the drive coil without permanent magnets.

8 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the drive coil is configured to generate the Lorentz force via generation of a magnetic field having a direction that is parallel to the main magnetic field of a magnetic resonance imaging system.

9 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the drive coil comprises a pair of annular windings that are wound along a plane perpendicular to an audio output direction, and

wherein the Lorentz force generated by the drive coil is parallel with the audio output direction.

10 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein each of the earphone body, the diaphragm, and the drive coil is magnetic resonance compatible to facilitate the magnetic-resonance imaging system compatible earphone functioning during a magnetic resonance examination.

11 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the earphone does not include a permanent magnet.

12 . The magnetic-resonance imaging system compatible earphone as claimed in claim 11 , wherein the drive coil is configured to generate the Lorentz force exclusively in response to the main magnetic field generated via the magnetic resonance imaging system without any magnetic field being generated by components of the earphone.

13 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the drive coil is configured to operate during a magnetic resonance imaging examination of a patient while being worn by the patient.

14 . The magnetic-resonance imaging system compatible earphone as claimed in claim 1 , wherein the drive coil is configured to generate the Lorentz force exclusively in response to the main magnetic field generated via the magnetic resonance imaging system without any magnetic field being generated by components of the earphone.

15 . A magnetic-resonance imaging system compatible intercom system, comprising:

a sound receiver, comprising:

a microphone configured to convert an audio signal to an analog signal,

a first audio codec configured to generate a digital signal based on the analog signal generated by the microphone, and

a first audio processor configured to generate an output signal based on the digital signal generated by the first audio codec; and

a sound transmitter, comprising:

a second audio processor configured to generate an input signal based on the output signal generated by the first audio processor;

a second audio codec configured to generate an analog signal based on the input signal; and

a magnetic-resonance imaging system compatible earphone configured to emit sound according to the analog signal generated by the second audio codec, the magnetic-resonance imaging system compatible earphone comprising:

an earphone body;

a diaphragm arranged on the earphone body;

a drive coil arranged on the earphone body, the drive coil being configured to receive audio current;

an elastic sheet disposed on the earphone body, the drive coil being fixed to the elastic sheet; and

a transmission member connecting the elastic sheet and the diaphragm,

wherein upon receiving the audio current, the drive coil is configured to generate a Lorentz force in response a main magnetic field that is generated via a magnetic resonance imaging system,

wherein the drive coil is configured to cause, via the Lorentz force generated by the drive coil, the elastic sheet to elastically deform to induce movement in the transmission member, and

wherein the movement of the transmission member drives the diaphragm to thereby generate sound via vibration.

16 . The magnetic-resonance imaging system compatible intercom system as claimed in claim 15 , further comprising:

first wireless communication circuitry connected to the first audio processor; and

second wireless communication circuitry connected to the second audio processor,

wherein the first audio processor and the second audio processor are configured to cause a transmission of signals, respectively, via wireless communication using the first wireless communication circuitry and the second wireless communication circuitry.

17 . The magnetic-resonance imaging system compatible intercom system as claimed in claim 15 , wherein:

the sound transmitter further comprises noise reduction circuitry configured to collect ambient noise and to convert the ambient noise into a further digital signal,

the noise reduction circuitry is connected to the second audio processor, and

the second audio processor is configured to generate the input signal based on the further digital signal generated by the noise reduction circuitry such that the magnetic-resonance imaging system compatible earphone emits a sound wave having the same amplitude but an opposite phase as a sound wave of the ambient noise.

18 . The magnetic-resonance imaging system compatible intercom system as claimed in claim 15 , wherein the sound transmitter further comprises a constant-current audio amplifier comprising an input end connected to the second audio codec and an output end connected to the magnetic-resonance compatible earphone.

19 . A head coil, comprising:

a body configured to accommodate a head of an examination subject and to receive magnetic resonance signals of the head of the examination subject;

a set of airbags, each one of the set of airbags being disposed on the body and respectively corresponding to two ears of the examination subject; and

a set of magnetic-resonance imaging system compatible earphones, each one of the set of magnetic-resonance imaging system compatible earphones comprising:

an earphone body;

a diaphragm arranged on the earphone body;

a drive coil arranged on the earphone body, the drive coil being configured to receive audio current;

an elastic sheet disposed on the earphone body, the drive coil being fixed to the elastic sheet; and

a transmission member connecting the elastic sheet and the diaphragm,

wherein upon receiving the audio current, the drive coil is configured to generate a Lorentz force in response to a main magnetic field that is generated via a magnetic resonance imaging system,

wherein the drive coil is configured to cause, via the Lorentz force generated by the drive coil, the elastic sheet to elastically deform to induce movement in the transmission member, and

wherein the movement of the transmission member drives the diaphragm to thereby generate sound via vibration,

wherein each one of the set of magnetic-resonance imaging system compatible earphones is respectively connected to each one of the set of air bags and configured to transmit sound to the two ears of the examination subject, and

wherein each one of the set of airbags is configured to be inflated and deflated to adjust a distance between each one of the set of the magnetic-resonance compatible earphones and a respective one of the two ears of the examination subject.