Loudspeaker to generate sustainable high quality auditory impression

1. A loudspeaker comprising:

a frame;

a vibration system accommodated in the frame and comprising a vibrating diaphragm and a voice coil for driving the vibrating diaphragm fixed with the frame;

a magnetic circuit system driving the vibration system, the magnetic circuit system comprising a yoke positioned by the frame and a magnet portion supported by the yoke;

a light source assembled with the voice coil;

a photosensitive sensor located in the yoke and within the irradiation scope of the light source;

wherein the light source is set at one end of the voice coil opposite to the yoke, and the light source and the photosensitive sensor are opposite to each other; and the magnet portion comprises a first magnet portion and a second magnet portion, and the second magnet portion locates around the first magnet portion and forms a magnetic gap with the first magnet portion, and the voice coil is inserted into the gap together with the light source.

2. The loudspeaker as described in claim 1 , wherein the photosensitive sensor is a photodiode, a phototransistor, a photoresistor or a photomultiplier.

3. The loudspeaker as described in claim 1 , wherein the photosensitive sensor is opposite to the magnet gap.

4. The loudspeaker as described in claim 3 wherein an installation slot is formed in the yoke, and the photosensitive sensor is installed in the installation slot.

5. The loudspeaker as described in claim 3 , wherein the vibrating diaphragm comprises a first suspension in a middle thereof, a second suspension and a dome located between the first suspension and the second suspension, and an inner periphery side of the first suspension is fixed to the first magnet portion, and one end of the voice coil away from the yoke is connected to the dome.