There is provided a particle detector system and to detect particles on target including reticle and pellicle. The system includes a light transmitting device adapted to transmit light beam to a target through an electrowetting microlens, a light receiving device adapted to receive the transmitted light beam reflected by a surface of the target, a light refraction angle adjusting controller adapted to apply a voltage to the electrowetting microlens in order to adjust an incident angle of the light irradiated, and a detector adapted to analyze the light received by the light receiving device to determine whether there are particles on a surface of the target.