Noise reduction earphone and earphone noise reduction method

A noise reduction earphone, comprising a sound emitting apparatus, wherein the sound emitting apparatus comprises:

• a cavity, an electroacoustic transducer, a first microphone, a second microphone, and a signal processing unit;
• the electroacoustic transducer is arranged in the cavity and divides the cavity into a first cavity and a second cavity, the first cavity is provided with a first sound outlet hole, and the second cavity is provided with a second sound outlet hole;
• the first microphone is arranged in the first cavity and is configured to collect a sound signal of the electroacoustic transducer in the first cavity and convert the sound signal into a first electrical signal S1;
• the second microphone is arranged close to the second sound outlet hole and is configured to collect a sound signal of the electroacoustic transducer in the second cavity and convert the sound signal into a second electrical signal S2;
• and
• the signal processing unit comprises a first signal processing circuit, a second signal processing circuit, and a first adder, the first signal processing circuit is configured to perform signal processing on the first electrical signal S1, a first processed electrical signal is S11, the second signal processing circuit is configured to perform signal processing on the second electrical signal S2, a second processed electrical signal is S12, and the first processed electrical signal S11 and the second processed electrical signal S12 have equal amplitudes and opposite phases;
• and the first adder is configured to process the first processed electrical signal S11 and the second processed electrical signal S12, a third processed electrical signal is S3, the third processed electrical signal S3 is transmitted to the electroacoustic transducer as an output signal of the signal processing unit, and an amplitude of the third processed electrical signal S3 is zero.