The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 1994
Filed:
Dec. 30, 1991
Eric G Rawson, Saratoga, CA (US);
Babur B Hadimioglu, Mountian View, CA (US);
Butrus T Khuri-Yakub, Palo Alto, CA (US);
Xerox Corporation, Stamford, CT (US);
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.