In-ear active noise reduction earphone

1. An in-ear active noise reduction earphone, comprising a housing, wherein

the housing comprises a rear chamber and a front chamber, and the housing is laterally provided with a sound generating unit separating the rear chamber from the front chamber;

the rear chamber is located at a top of the housing, a feedforward microphone is installed inside the rear chamber, the front chamber is located at a bottom of the housing, and a feedback microphone is installed inside the front chamber; and

wherein, the front chamber comprises a first front chamber and a second front chamber, and the feedback microphone is installed inside the second front chamber; and

wherein the first front chamber is arranged below the sound generating unit;

the second front chamber is arranged at one side of the first front chamber and between the rear chamber and the first front chamber, and separates the rear chamber from the front chamber together with the sound generating unit; and

the second front chamber and the first front chamber are separated from each other by a diaphragm having a through hole at a middle of the diaphragm.

2. The in-ear active noise reduction earphone according claim 1 , wherein

a sound output tube is formed in the first front chamber, and a bottom portion of the first front chamber is a sound output port for outputting sound; and

a sound generating face of the sound generating unit faces downward toward the sound output port of the first front chamber, and the second front chamber is arranged at a side, away from the sound output port, of the first front chamber.

3. The in-ear active noise reduction earphone according to claim 2 , wherein the second front chamber comprises a chamber body and a sealing cover for sealing the chamber body, and one side, close to the rear chamber, of the chamber body is sealed by the sealing cover, to be separated from the rear chamber.

4. The in-ear active noise reduction earphone according to claim 2 , wherein the second front chamber comprises a chamber body and a sealant for sealing the chamber body, and one side, close to the rear chamber, of the chamber body is sealed by the sealant, to be separated from the rear chamber.

5. The in-ear active noise reduction earphone according to claim 3 , wherein the feedback microphone is vertically arranged inside the second front chamber, to allow a sound receiving face of the feedback microphone to face left or right, and a center line direction of the feedback microphone, along the sound receiving face, is at an angle to a center line direction of the sound generating unit.

6. The in-ear active noise reduction earphone according to claim 4 , wherein the feedback microphone is vertically arranged inside the second front chamber, to allow a sound receiving face of the feedback microphone to face left or right, and a center line direction of the feedback microphone, along the sound receiving face, is at an angle to a center line direction of the sound generating unit.

7. The in-ear active noise reduction earphone according to claim 5 , wherein the angle is 90 degrees.

8. The in-ear active noise reduction earphone according to claim 5 , wherein a diameter of the sound generating unit is smaller than or equal to 10 mm.

9. The in-ear active noise reduction earphone according to claim 4 , wherein the sealant is an elastic sealant.

10. The in-ear active noise reduction earphone according to claim 6 , wherein the angle is 90 degrees.

11. The in-ear active noise reduction earphone according to claim 6 , wherein a diameter of the sound generating unit is smaller than or equal to 10 mm.