Matsushita Electric Industrial Co., Ltd.

Olympus Medical Systems Corporation

Yasuteru Asakawa

Toshio Ishizaki

Toru Yamada

Hiroaki Kosugi

Osamu Kawasaki

Tomoki Uwano

Yukihiko Ise

Akira Fujishima

Masatoshi Homan

Naoki Yuda

Eiji Okada

Hiroshi Fukushima

Yukio Kashiwagi

An oscillator device includes a resonator including a coil and a capacitor connected to the coil in parallel; and an oscillator connected to the resonator. Electric waves are emitted from the coil to at least one receiving antenna of the receiver while the oscillator device changes position and direction over time. The coil has an outer diameter and a total length which is approximately the same as the outer diameter.

Oscillator device and transmitter module using same

A piezoelectric filter is one not changing in the holding position a resonator in spite of impulse, small in the number of parts, easy to assemble from one direction, small, thin, and stable in characteristic. For example, as shown in FIG. 7, on electrode patterns on a package 10 forming wiring electrode patterns 11, holding protrusions 13 for holding resonators, and partition boards 14 for positioning resonators, a rectangular plate type piezoelectric resonators 12 are adhered with conductive adhesive. The rectangular plate type piezoelectric resonators 12 and the package 10 are adhered and reinforced from above with a vibration absorbing member 15, and wiring is formed from above the resonators by wire bonding 16, thereby wiring resonators in a ladder form. Or, as shown in FIG. 11, after forming electrode patterns 102 on a piezoelectric substrate 101, a rectangular plate resonator 104 is cut out from a piezoelectric substrate 101 by laser in a shape consecutive to the piezoelectric substrate 101 by the node of the length expander mode, and the piezoelectric substrate 101 is enclosed by a spacer 106 and a sheet 107 from above and beneath.

Piezoelectric filter, its manufacturing method, and intermediate

A piezoelectric filter is one not changing in the holding position of resonator in spite of impulse, small in the number of parts, easy to assemble from one direction, small, thin, and stable in characteristic. For example, as shown in FIG. 7, on electrode patterns on a package 10 forming wiring electrode patterns 11, holding protrusions 13 for holding resonators, and partition boards 14 for positioning resonators, a rectangular plate type piezoelectric resonators 12 are adhered with conductive adhesive. The rectangular plate type piezoelectric resonators 12 and the package 10 are adhered and reinforced from above with a vibration absorbing member 15, and wiring is formed from above the resonators by a wire bonding 16, thereby wiring resonators in a ladder form. Or, as shown in FIG. 11, after forming electrode patterns 102 on a piezoelectric substrate 101, a rectangular plate resonator 104 is cut out from a piezoelectric substrate 101 by laser in a shape consecutive to the piezoelectric substrate 101 by the node of length expander mode, and the piezoelectric substrate 101 is enclosed by a spacer 106 and a sheet 107 from above and beneath.

Piezoelectric filter of the ladder type

Ladder type intermediate frequency filter

In a piezoelectric resonator having a piezoelectric bar formed in a substantial rectangular parallelopiped and electrodes formed on a pair of confronting surfaces of the piezoelectric bar for resonating in the length expander mode, the piezoelectric bar has at least a bevel portion extending the longitudinal direction. In a ladder filter having series and parallel piezoelectric resonators, the series piezoelectric resonator has the bevel portion to shift a frequency of a spurious response to that of the parallel piezoelectric resonator to suppress the spurious response. It is disclosed that a second piezoelectric resonator has a piezoelectric bar formed in a rectangular parallelopiped has a length L, a width W, and a thickness T wherein L&gt;W&gt;T; and electrodes formed on a pair of confronting surfaces defined by L and T. Another ladder filter includes the second piezoelectric resonator as the series resonator to decrease a capacitance between the electrodes to increase an amount of attenuation. In the second piezoelectric resonator, when W&lt;T and 0.42&lt;T/L&lt;2.5, a coupling factor is large.

Piezoelectric resonator and piezoelectric filter

Growing community of inventors

Katano, Japan

Yasuteru Asakawa