Murata Manufacturing Co., Ltd.

Yukio Higuchi

Hirotsugu Abe

Masayoshi Katsube

Shigeyuki Mikami

Mitsuru Sube

Nobuhiko Tanaka

Toru Kurisu

Wataru Yanase

A ceramic material powder for a translucent ceramic is molded with a binder, and the resulting green compact is embedded in a ceramic powder having the same composition with the ceramic material powder. After removing the binder, the green compact embedded in the ceramic powder is fired in an atmosphere having an oxygen concentration higher than that in the removal procedure of the binder and thereby yields a translucent ceramic represented by Formula I: Ba{(SnZr)MgTa}O, Formula II: Ba(ZrMgTa)Oor Formula III: Ba{(SnZr)(ZnMg)Nb}O. The translucent ceramic has a refractive index of 1.9 or more and is paraelectric.

Method of producing translucent ceramic

A ceramic material powder for a translucent ceramic is molded with a binder, and the resulting green compact is embedded in a ceramic powder having the same composition with the ceramic material powder. After removing the binder, the green compact embedded in the ceramic powder is fired in an atmosphere having an oxygen concentration higher than that in the removal procedure of the binder and thereby yields a translucent ceramic represented by Formula I: Ba{(SnZr)MgTa}O, Formula II: Ba(ZrMgTa)Oor Formula III: Ba{(SnZr)ZnMg)Nb}O. The translucent ceramic has a refractive index of 1.9 or more and is paraelectric.

Transparent ceramic and method for production thereof, and optical element

An interface F between upper mandrels and lower mandrels are moved to a predetermined position in a cavity with the upper mandrels and the lower mandrels slidingly moving toward the lower punch while the upper mandrels and the lower mandrels remain in contact with each other, in a manner such that pressure is not applied to powdered dielectric material disposed in the cavity. The powdered dielectric material in the cavity is compressed by an upper punch and the lower punch while the upper mandrels and the lower mandrels remain in contact with each other, thereby forming a dielectric block.

Method for press-molding dielectric block

A dielectric resonator comprising a resonator section and a supporting base section which are made of the same dielectric material as a single unit. The resonator section and the supporting base section have substantially the same outside diameter. A concave section having a trapezoidal cross-sectional shape is provided within the supporting base section such that the inside diameter of the supporting base section becomes smaller in the direction from the end face, which is used as a mounting face, and toward the resonator section.

Dielectric resonator, filter, duplexer, oscillator and communication apparatus

A frequency adjustment mechanism for a dielectric resonator in which a change of a unloaded Q is small by adjustment of a resonating frequency, a tuning rod may be stably fixed in place after the adjustment without using any adhesives or the like and it is possible to readily perform the re-adjustment. A hole 14 is provided at an axially central portion of the dielectric resonator 11 and the tuning rod 15 is threadingly inserted into the hole 14. A female screw thread 14a is formed in an inner circumferential surface of the hole 14, and a male screw thread 15a is formed on an outer circumferential surface of the tuning rod 15. Resin layers 16 and 17 are formed on surfaces of the female screw thread 14a and the male screw thread 15a, respectively. The tuning rod 15 is made of dielectric material having a low loss and a high dielectric constant. The resin layers 16 and 17 are made of resin material having an elasticity and a low loss.

Dielectric resonator frequency adjusting mechanism with a resin layer

A mechanism for adjusting the resonance frequency of a dielectric resonator having TE.sub.01.delta. mode as its operation mode under the presence of the electromagnetic field including: a hole extending along the axis of the dielectric resonator; a tuning bar, made of a dielectric material of a low loss, having a male screw formed on the peripheral surface thereof; and a female screw, to engage the male screw, formed on the wall of the hole. The tuning bar is reciprocated in the hole with the tuning bar engaging the hole so as to adjust the resonance frequency.

Mechanism for adjusting resonance frequency of dielectric resonator

A dielectric ceramic composition for high frequencies comprises a main component of a TiO.sub.2 -ZrO.sub.2 -Sn.sub.2 O system and contains, as additives, not more than 7 wt % of ZnO, not more than 10 wt % of NiO, and not more than 7 wt % of one metal oxide selected from the group consisting of Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, WO.sub.3 and Sb.sub.2 O.sub.5. The main component consists essentially of 22 to 43 wt % of TiO.sub.2, 38 to 58 wt % of ZrO.sub.2, and 9 to 26 wt % of SnO.sub.2.

Growing community of inventors

Omihachiman, Japan

Yukio Higuchi