Crystal unit, semimanufactured crystal unit, and method for manufacturing crystal unit
AssigneeNihon Dempa Kogyo Co., Ltd.
InventorsKiyoharu Matsuo, Takahiro Ohtsuka
Life of this patent
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Abstract
A crystal unit includes a crystal element, excitation electrodes, and a container. The crystal element vibrates in a thickness-shear mode. The excitation electrodes are disposed on front and back surfaces of the crystal element. The crystal element is mounted to the container. The excitation electrodes are disposed on the crystal element. When a thickness of the crystal element is expressed as T, and a total thickness of the excitation electrodes disposed on the front and back surfaces of the crystal element is expressed as t, a ratio t/T is from 0.026 to 0.030.
Claims16
A crystal unit comprising:
- a crystal element that vibrates in a thickness-shear mode;
- excitation electrodes disposed on front and back surfaces of the crystal element;
- and
- a container to which the crystal element is mounted, the excitation electrodes being disposed on the crystal element, wherein
- when a thickness of the crystal element is expressed as T, and a total thickness of the excitation electrodes disposed on the front and back surfaces of the crystal element is expressed as t, a ratio t/T is from 0.026 to 0.030.
A crystal unit comprising:
- a crystal element that vibrates in a thickness-shear mode;
- excitation electrodes disposed on front and back surfaces of the crystal element;
- and
- a container to which the crystal element is mounted, the excitation electrodes being disposed on the crystal element, wherein
- when a mass of a crystal in a region of the crystal element in which the excitation electrodes are disposed is expressed as M, and a mass of the excitation electrodes on the front and back surfaces in the region is expressed as m, a ratio m/M is from 0.192 to 0.216.
A semimanufactured crystal unit comprising
- a wafer that includes a plurality of quartz-crystal vibrating pieces arranged in a matrix, wherein
- the quartz-crystal vibrating pieces each include a crystal element and excitation electrodes disposed on front and back principal surfaces of the crystal element, and
- when a thickness of the crystal element is expressed as T, and a total thickness of the excitation electrodes disposed on the front and back surfaces of the crystal element is expressed as t, or when a mass of a crystal in a region of the crystal element in which the excitation electrodes are disposed is expressed as M, and a mass of the excitation electrodes on the front and back surfaces in the region is expressed as m, a ratio t/T is from 0.026 to 0.030, or a ratio m/M is from 0.192 to 0.216.
Dependencies are inferred from the claim text.