The present disclosure relates to ejector mechanisms and devices for generating a directed stream of droplets, as well as improved methods for delivering an ejected stream of droplets to a target. The device and methods may be useful for the delivery of fluid for ophthalmic, topical, oral, nasal, or pulmonary use, more particularly, for use in the delivery of ophthalmic fluid to the eye. Certain aspects of the disclosure relate to devices and methods for the delivery of a therapeutically effective low dosage volume medicament composition to a target, e.g., by controlling charge, droplet size and/or droplet deposit parameters of the medicament composition.
