Particulate matter scattered light collecting device, laser diameter measuring system and mass spectrometer

The utility model relates to a particulate matter scattered light collecting device, a laser diameter measuring system and a mass spectrometer. The particulate matter scattered light collecting devicecomprises a front-end collecting assembly, an optical fiber assembly and a photoelectric detection assembly, the front-end collection assembly is used for collecting and converging scattered light; the optical fiber assembly is used for conducting scattered light gathered by the front-end collection assembly; the photoelectric detection assembly corresponds to the optical fiber assembly and is used for receiving the light beam transmitted by the optical fiber assembly and converting an optical signal of the light beam into an electric pulse signal. The particulate matter scattered light collecting device can improve the accuracy and efficiency of particulate matter measurement. The utility model also relates to a laser diameter measuring system and a mass spectrometer. The geometric dimension of the laser diamete