Cavitational liquid impact printer

摘要

An ink jet printhead for use in a thermal ink jet printer having bubble-generating heating elements formed symmetrically around the entrances to passageways in the ink-holding printhead chamber that terminate as nozzles. The heating elements are individually addressable with current pulses to form vapor bubbles, which, during collapse, produce an impact force that expels and propels droplets toward a recording medium. An alternate embodiment includes an ultrasonic generator in the printhead chamber to produce pressure waves in the ink contained in the chamber. The current pulse applied to the heating element is synchronized with the lower pressure wave to obtain bubble growth with substantially lower temperatures resulting in a more energy efficient printhead.