To provide a droplet weight measurement method for precisely measuring the weight of droplets.
The droplet weight measurement method comprises: a step for detecting the resonance frequency of a piezoelectric vibrator before droplets adhere to an electrode 110b provided in the piezoelectric vibrator 110; a step for detecting the resonance frequency of the piezoelectric vibrator after droplets adhere to the electrode; a step for obtaining the amount of change in the resonance frequency before and after the detected droplets adhere; a step for obtaining the viscosity of the droplets, based on the amount of change in the resonance resistance in the piezoelectric vibrator after the droplets adhere to the electrode, or in the resonance resistance of the piezoelectric vibrator before and after the droplets adhere to the electrode; a step for obtaining the amount of resonance frequencies that are changed by the viscosity of the droplets; and a step for obtaining the weight of the droplets, based on the amount of change in the resonance frequency before and after the adhesion of the droplets and the amount of resonance frequency that is changed by the viscosity of the droplets.
Fujitsuna Hideyoshi
Osamu Suzawa