Fujifilm Corporation

Fuji Photo Film Company, Limited

Tetsu Miyoshi

Daisuke Inoue

Naoki Murakami

Shin Ozawa

Yusuke Hatanaka

Akihito Fukunaga

Takashi Nakamura

Kazuo Hiraguchi

Jun Sato

Tsutomu Sasaki

Yukio Sakashita

Teruo Ashikawa

Yusuke Kagawa

Samito Nakamura

Akito Fukunaga

An object is to provide a laminated piezoelectric element capable of preventing a short circuit between adjacent piezoelectric films and an electroacoustic transducer using the laminated piezoelectric element. The object is solved by laminating a plurality of layers of piezoelectric films polarized in a thickness direction, in which a piezoelectric layer is interposed between two thin film electrodes, and causing polarization directions of the adjacent piezoelectric films to be opposite to each other.

Laminated piezoelectric element and electroacoustic transducer

Provided are a laminated piezoelectric element and an electroacoustic transducer capable of obtaining high piezoelectric characteristics and easily ensuring an electric contact to an electrode layer. A plurality of layers of piezoelectric films, each of which is formed by laminating a first protective layer, a first electrode layer, a piezoelectric layer, a second electrode layer, and a second protective layer in this order, are laminated. Each of the piezoelectric layers is polarized in a thickness direction. In each of the piezoelectric films, the first electrode is disposed on an upstream side in a polarization direction of the piezoelectric layer, and the second electrode is disposed on a downstream side. Each of the plurality of piezoelectric films has a cemented portion which is cemented to an adjacent piezoelectric film and a protruding portion which is not cemented to the adjacent piezoelectric film and in which at least the first electrode layer and the first protective layer or the second electrode layer and the second protective layer protrude from the cemented portion toward the outside in a plane direction. At the protruding portion of each of the piezoelectric films, at least one of a first contact, to which the first electrode layers of the piezoelectric films are electrically connected to each other, or a second contact, to which the second electrode layers of the piezoelectric films are electrically connected to each other, is formed.

An object is to provide a piezoelectric film that has excellent flexibility in a high temperature environment at higher than 50&#xb0; C. and exhibits good flexibility even at room temperature, a laminated piezoelectric element in which the piezoelectric films are laminated, and an electroacoustic transducer using the piezoelectric film or the laminated piezoelectric element. The object is solved by the piezoelectric film including: a polymer-based piezoelectric composite material in which piezoelectric particles are dispersed in a matrix including a polymer material; and electrode layers provided on both surfaces of the polymer-based piezoelectric composite material, in which a loss tangent at a frequency of 1 Hz according to dynamic viscoelasticity measurement has a maximal value of greater than or equal to 0.1 existing in a temperature range of higher than 50&#xb0; C. and lower than or equal to 150&#xb0; C., and has a value of greater than or equal to 0.08 at 50&#xb0; C.

Piezoelectric film, laminated piezoelectric element, and electroacoustic transducer

An object is to provide a piezoelectric film that has excellent flexibility in a sub-zero environment and exhibits the required flexibility even at room temperature, a laminated piezoelectric element in which the piezoelectric films are laminated, and an electroacoustic transducer using the piezoelectric film or the laminated piezoelectric element. The object is solved by the piezoelectric film including: a polymer-based piezoelectric composite material in which piezoelectric particles are dispersed in a matrix including a polymer material; and electrode layers formed on both surfaces of the polymer-based piezoelectric composite material, in which a loss tangent at a frequency of 1 Hz according to dynamic viscoelasticity measurement has a maximal value of greater than or equal to 0.1 existing in a temperature range of higher than or equal to &#x2212;80&#xb0; C. and lower than 0&#xb0; C., and has a value of greater than or equal to 0.05 at 0&#xb0; C.

Provided are an electroacoustic transduction film capable of reproducing a sound with a sufficient sound volume at a high conversion efficiency, a manufacturing method thereof, an electroacoustic transducer, a flexible display, a vocal cord microphone, and a sensor for a musical instrument. The electroacoustic transduction film includes: a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature; two thin film electrodes laminated on both surfaces of the polymer composite piezoelectric body; and two protective layers respectively laminated on the two thin film electrodes, in which an intensity ratio &#x3b1;=(002) plane peak intensity/((002) plane peak intensity+(200) plane peak intensity) between a (002) plane peak intensity and a (200) plane peak intensity derived from the piezoelectric body particles in a case where the polymer composite piezoelectric body is evaluated by an X-ray diffraction method is more than or equal to 0.6 and less than 1.

Electroacoustic transduction film and manufacturing method thereof, electroacoustic transducer, flexible display, vocal cord microphone, sensor for musical instrument

Provided are an electroacoustic conversion film web, an electroacoustic conversion film, and a method of manufacturing an electroacoustic conversion film web in which costs can be reduced by reducing the number of operations without damage to thin film electrodes, the points of electrode lead-out portions can be freely determined, and thus high productivity can be achieved. A preparation step of preparing an electrode laminated body in which a single thin film electrode and a single protective layer are laminated and a lamination step of laminating the electrode laminated body and an piezoelectric layer are included. A non-adhered portion that is not adhered to the piezoelectric layer is provided in at least one end portion of the thin film electrode in a case where the electrode laminated body and the piezoelectric layer are laminated in the lamination step.

Electroacoustic conversion film web, electroacoustic conversion film, and method of manufacturing an electroacoustic conversion film web

Provided are a pickup sensor and a biological sensor that are small-sized and can detect micro vibration efficiently and stably with high accuracy. The pickup sensor includes an electroacoustic converter film including: a piezoelectric polymer composite in which piezoelectric particles are dispersed in a viscoelastic matrix that is formed of a polymer material having viscoelasticity at normal temperature; two thin film electrodes that are laminated on opposite surfaces of the piezoelectric polymer composite, respectively; and a protective layer that is laminated on at least one of the two thin film electrodes, in which at least a part of a surface of the electroacoustic converter film is an abutting surface that abuts against a test object, and the thin film electrode on a surface opposite to the abutting surface is grounded.

Pickup sensor and biological sensor

An electroacoustic transduction film including a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature, and thin film electrodes respectively laminated on both surfaces of the polymer composite piezoelectric body is included, and two or more of the electroacoustic transduction films are laminated, and a gap between the adjacent electroacoustic transduction films is less than or equal to 3 cm.

Electroacoustic transducer

Provided is an electroacoustic transducer capable of reducing the thickness and weight of the entire pillow when a speaker is embedded in the pillow or a headrest, enabling miniaturization of a device by causing the position of the speaker to be close to a position at which the head is placed, and improving the accuracy of signal processing by reducing a load of the signal processing in a case where active noise control is performed, thereby improving a noise reduction effect. The electroacoustic transducer includes: an electroacoustic transduction unit having an electroacoustic transduction film including a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature and thin film electrodes respectively laminated on both surfaces of the polymer composite piezoelectric body, and an elastic support disposed in close contact with one principal surface to bend the shape of the electroacoustic transduction film; and a first cushion layer that is in contact with the electroacoustic transduction film on an electroacoustic transduction film side of the electroacoustic transduction unit to cover the electroacoustic transduction unit and is formed of a three-dimensional solid knitted fabric.

Provided is a video audio system including electroacoustic conversion units which include an electroacoustic conversion film having a macromolecular composite piezoelectric body formed by dispersing piezoelectric body particles in a viscoelastic matrix formed of a macromolecular material that is viscoelastic at normal temperature and thin film electrodes respectively laminated on both surfaces of the macromolecular composite piezoelectric body, curve and support the electroacoustic conversion film, and use at least a part of the electroacoustic conversion film as vibration regions and a display device which is a screen or a video display device to which videos are projected, in which at least one of the electroacoustic conversion units is disposed on a rear surface opposite to a surface of the display device on which videos are displayed, the plurality of vibration regions is arranged on the entire rear surface of the display device, and location information of the vibration regions is included in sound data that are input to the electroacoustic conversion units.

Video audio system

An omnidirectional electroacoustic transducer capable of reproducing a sound with high acoustic quality and sufficient sound volume in a wide frequency band is provided with a small number of components. The electroacoustic transducer includes: two or more electroacoustic transduction units each including an electroacoustic transduction film and an elastic supporter, the electroacoustic transduction film having a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature, and two thin film electrodes laminated on both surfaces of the polymer composite piezoelectric body, and the elastic supporter being disposed to be closely attached to one principal surface of the electroacoustic transduction film so as to cause the electroacoustic transduction film to be bent, in which the two or more electroacoustic transduction units are disposed so that the electroacoustic transduction films face outward and form some or all of faces of a polyhedron.

Provided are an electroacoustic transducer capable of stably reproducing a sound with high acoustic quality and widening a frequency band that is able to be reproduced, and an electroacoustic transduction system. In the electroacoustic transducer including: an electroacoustic transduction film including a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature, and two thin film electrodes laminated on both surfaces of the polymer composite piezoelectric body; and an elastic supporter which is disposed to be closely attached to one principal surface of the electroacoustic transduction film so as to cause the electroacoustic transduction film to be bent, a bent portion of the electroacoustic transduction film has a quadrangular shape, a length of a short side of the bent portion is less than or equal to 10 cm, and a length of a long side thereof is greater than or equal to 30 cm.

Growing community of inventors

Ashigarakami-gun, Japan

Tetsu Miyoshi