Abstract: Different aperture fiber were applied for transmission of laser and scattered photons,different aperture y-type fiber were used for transmission of incident and scattered light synchronously.Based on photon correlation spectroscopy the nanometer particle measuring system was designed.Besides,the affects of fiber core diameter,microscope objectives numerical aperture,temperature and scattering angle were discussed.Experiments show that it is accurate and stable for nano-particle size distribution measurement,all experiments were finished in super clean room,in which temperature was controlled at about 13~22 ℃.

Key words: photon correlation spectroscopy (PCS), nano-particles, measurement system, single scattered system, double scattered system