Acoustic ink printhead
US5339101A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1991 |
| Grant date | Aug 16, 1994 |
| Priority date | — |
| Expiry date | Dec 30, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2002/14322
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A printhead for an acoustic ink printer has a piezoelectric transducer on one surface of a substrate. A layer of a dielectric material is provided on the surface of the transducer away from the substrate. A Fresnel lens is formed in the surface of the dielectric layer away from the transducer, for focusing sound energy near the surface of a body of ink adjacent the dielectric layer. Thus the transducer and lens are both on the same side of the substrate. A pit may be formed in the substrate under the transducer. The transducer may be a body of piezoelectric material sandwiched between a pair of electrodes, the lower electrode of which has a thickness that is a quarter wave at the excitation frequency of the transducer. An anti-reflective coating may be provided on the lower surface of the substrate, with a body of an absorptive material abutting the anti-reflective layer, or an absorptive material having an acoustic impedance approximately matching that of the substrate may be coated on the lower surface of the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.