Airflow Generating Device with Differential Modulation Driving and Asymmetric Initial Deflection

An airflow generating device, comprising:

• a first cell, disposed within a first region;
• and
• a second cell, disposed within a second region;
• wherein the first cell generates a first air pressure with a first polarity in the first region and the second cell generates a second air pressure with a second polarity in the second region;
• wherein the second polarity is opposite to the first polarity;
• wherein at least one of the first and second cells comprises a film structure, the film structure comprises a flap pair, the flap pair comprises a first flap and a second flap opposite to each other;
• wherein the flap pair possesses an initial deflection difference or exhibits an average displacement difference between the first flap and the second flap;
• wherein the flap pair operates at an ultrasonic frequency, such that the airflow generating device produces a plurality of air pulses at an ultrasonic pulse rate.