A high density multi-channel array, electrically pulsed droplet deposition apparatus comprises a bottom sheet of piezoelectric material poled in a direction normal to said sheet and formed with a plurality of parallel channels mutually spaced in an array direction normal to the length of said channels....http://www.google.se/patents/US5016028?utm_source=gb-gplus-sharePatent US5016028 - High density multi-channel array, electrically pulsed droplet deposition apparatus
