Method for ejecting ink droplets in an acoustic ink printer and a piezoelectric transducer for an ink printer

摘要

An acoustic ink printer transducer comprises a piezoelectric layer (13) positioned between two suitable electrode materials (12,14). To enable ejection of a number of different ink droplet sizes from the acoustic ink printer, thereby facilitating grey scale printing, the piezoelectric layer (13) and one (14) of the electrode layers have an acoustic thickness of λ/4, where λ is the wavelength at the fundamental resonant frequency ωo of the transducer.