Murata Manufacturing Co., Ltd.

Hideo Adachi

Kiichi Minai

Shunjiro Imagawa

Tadashi Takaya

Sasuga Kakehi

Kozo Moriyasu

Nobuhiko Nakagawa

A piezoelectric loudspeaker using a thin plate of piezoelectric ceramics of a high dielectric constant, and fixing a piezoelectric transducer including a thin plate of piezoelectric ceramic of a high dielectric constant onto a diaphragm stretched on a frame, thereby forming a sound generator. The piezoelectric loudspeaker is so constructed that the resonance frequency of the sound generator is set at the low frequency band side of an audio frequency region and that of a cavity by the frame is set at the high frequency band side, the thin plate piezoelectric ceramic of high dielectric constant being used, so that the piezoelectric loudspeaker is of an ultrathin type and can cover the whole audio frequency region.

Piezoelectric loudspeaker

An infrared radiation sensing device such as a pyroelectric effect device is mounted on one surface of an insulating substrate of alumina ceramic or the like. External connection leads are provided on the insulating substrate. A hollow cylindrical member is mounted on its end on the radiation receiving surface of the infrared radiation sensing device. A field effect transistor is provided on the other surface of the insulating substrate for amplifying the signal generated in the sensing device by incident infrared radiation. The apparatus is suitably encapsulated in a layer of resin.

Infrared radiation detecting apparatus and method of manufacturing it

An infrared radiation sensing device such as a pyroelectric effect device is mounted on one surface of an insulating substrate of alumina ceramic or the like. External connection leads are provided on the insulating substrate. A field effect transistor is provided on the other surface of the insulating substrate for amplifying the signal generated in the sensing device by incident infrared radiation. The apparatus is suitably encapsulated in a layer of resin.

Growing community of inventors

Kyoto, Japan

Hideo Adachi