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:
May. 11, 1999
Filed:
Aug. 29, 1997
John E Mattson, Streamwood, IL (US);
James F Caruba, Bartlett, IL (US);
Charles Zimnicki, Bartlett, IL (US);
Beverly A Carroll, Marengo, IL (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
A resonator (104) including a piezoelectric plate (102) with an electrode (108) having a random pattern (100) along a portion of an edge of the electrode (108). The random pattern (100) dampens or destructively interferes with undesirable and inharmonic vibrational modes. For example, a rectangular AT-cut quartz resonator, which vibrates in a thickness-shear mode may also possess undesirable flexure and face-shear modes. These modes not only present undesirable spurious frequencies, they also change over temperature, disturbing a frequency-ternperature response of the resonator. The random pattern (100) causes diffuse and/or specular scattering to reduce these undesirable modes, providing a more uniform frequency-temperature response which is beneficial in temperature compensated crystal oscillator applications.