The present application discloses a
system and a method for calculating a droplet
delay time in a liquid flow of a sorting device. The
system includes: a first
laser source configured to emit a first
laser beam to a liquid flow of a sorting device, the first
laser beam and the liquid flow intersecting at a first laser interrogation point; a second
laser source configured to emit a second laser beam to the liquid flow, the second laser beam and the liquid flow intersecting at a second laser interrogation point; and a droplet
delay time calculation unit configured to calculate, based on of the time when the particle in the liquid flow passes through the first and second laser interrogation point and the time when the particle passes through the second laser interrogation point, a first
delay time, and calculate, a droplet
delay time.