Abstract: A method of controlling evaporation of droplet cloud resulting from nebulization of a liquid expelled from a liquid droplet spray device is disclosed, wherein the liquid droplet spray device comprises a reservoir containing liquid, a perforate membrane plate, a fluid interface for feeding liquid from the reservoir to the membrane plate, an ultrasound generating mechanism for acting on the supplied liquid to cause it to be expelled as a spray of droplets through orifices of the membrane plate, and an electronic control device for controlling activation of the ultrasound generating mechanism.

Abstract: Volatile liquid droplet dispenser device, comprising: a first substrate having a space for containing liquid, and liquid outlet means for ejecting liquid from the device, the space arranged proximate to the liquid outlet means so liquid may exit the space by traversing the liquid outlet means, a second substrate comprising a support for receiving and holding the first substrate, and a vibrating element arranged to actuate liquid in the space so liquid undergoes vibration and contacts the liquid outlet means thereby exiting the device as a liquid droplet spray, wherein the liquid outlet means comprises a perforated nozzle membrane having a plurality of outlet nozzles, and an actuating element arranged between the vibrating element and the first substrate, and a sealing element arranged between the actuating element and the first substrate, wherein the actuating element and the sealing element are arranged to transmit ultrasound energy to liquid in the space.

Abstract: A method of controlling evaporation of droplet cloud resulting from nebulization of a liquid expelled from a liquid droplet spray device is disclosed, wherein the liquid droplet spray device comprises a reservoir containing liquid, a perforate membrane plate, fluid interface means for feeding liquid from the reservoir to the membrane plate, ultrasound generating means for acting on the supplied liquid to cause it to be expelled as a spray of droplets through orifices of the membrane plate, and electronic control means for controlling activation of the ultrasound generating means.