Matsushita Electric Industrial Co., Ltd.

Ritsuo Inaba

Kiyotaka Wasa

Osamu Kawasaki

Katsu Takeda

Yukio Kasahara

Yoshio Kishimoto

Shusuke Ono

Mikiko Matsuo

Tsuneo Mitsuyu

Hiromi Tanoue

Akira Tokushima

Tetsuji Fukada

Toru Kishi

Nobukazu Sugano

Horiyuki Harao

Ken-ichiroh Takahashi

Akira Tokusima

Yukihiro Matsuyama

An electroluminescent device includes a transparent substrate, a transparent anode, a thin film electrode and a light emitting organic polymer layer. Both of the surface of the transparent substrate and the surface of the transparent anode are imparted hydrophobicity so that an excellent electroluminescent device which hardly causes change in luminance with a lapse of time and has few dark spots can be obtained. Also a new polymer film is used as the transparent substrate so that a thin and flexible electroluminescent device, which hardly causes change in luminance with a lapse of time and has few dark spots, can be obtained. Also a new construction color electroluminescent display panel is described, which can be made flexible and reduced in thickness, long life, superior in resolution and easily produced.

Electroluminescent device

The present invention is to provide a organic light emitting device with high efficiency and long life of emitting light. The light emitting device comprises a positive electrode, a hole transporting layer, an electron transporting layer and a negative electrode on a substrate, the hole transporting layer if formed of triphenylamine tetramer as the major component, and 5,6,11,12-tetraphenylnaphthacene or 9,10-diphenylanthracene is added in a amount of 0.1-10% in the hole transporting layer. The hole transporting layer acts as a light emitting layer and suppressing reduction of luminance of the light and prevent the black spots from occurring and expanding so as to extend the life time. Furthermore, in the present invention, the transparent positive electrode is composed from two-layer structure comprising a hole injecting layer and a current distributing layer, this restricting occurrence of the black spots and reduction of the luminance due to the positive electrode.

Organic light emitting device and method for producing the same

In a driving apparatus for ultrasonic motor, a variable oscillator (44) varies oscillating frequency responding to current level of detected current which flows to a piezoelectric member (1, 2) and is in proportion to mechanical vibration of the piezoelectric member (1, 2) when mechanical resonance frequency varies by change of environmental condition.

Driving apparatus for ultrasonic motor

A method of driving an ultrasonic motor having a rotation body (6) which is rotated by travelling waves generated in a vibrator body (3), whereby the drive frequency of the motor is controlled in accordance with the value of an operating parameter such as phase difference between drive current and voltage, such as to maintain the drive frequency at a value which is lower than the antiresonance frequency of the vibrator body (3) and higher than a highest resonance frequency of the vibrator body (3) in a hysteresis loop exhibited by a resonance frequency characteristic of the vibrator body (3). Continuous stable operation is attained, irrespective of the effects of temperature and load changes upon the motor operating characteristics.

Drive method for ultrasonic motor providing enhanced stability of

Ultrasonic motor with stator projections and at least two concentric

Infrared detector

A piezoelectric motor wherein a stator comprising piezoelectric vibrators of rectangular or circular plate form pasted with a metal is used as a power source and a mechanical vibration in two directions, longitudinal and widthwise directions or radial and tangential directions, is converted into a rotary or linear motion through frictional force.

Piezoelectric motor

An electrostatic voltage sensor which includes a surface acoustic wave propagating medium and transmitting and receiving transducers coupled to the medium. The voltage sensor is provided with a separate voltage collecting member different from the electrode for applying a voltage or electric field, and the voltage obtained in the voltage collecting member is varied by a predetermined frequency for being applied to the electrode so as to detect external voltage by the variation component of the oscillating frequency.

Electrostatic voltage sensor

A voltage measuring device includes a surface acoustic wave propagating medium and transmitting and receiving transducers coupled to the medium. An electrode that receives an unknown voltage is applied to the medium for effecting, when the unknown voltage is supplied, a frequency change in the acoustic wave propagating through the medium. A detector is provided for detecting the frequency change which is an indication of voltage supplied to the electrode.

Voltage measuring device

A surface acoustic wave transducer has a multilayered substrate which is made of a nonpiezoelectric plate which has a surface which is coated with a piezoelectric film, and has an interdigital electrode which is disposed on or under the surface of the piezoelectric film. The interdigital electrode has a split structure and the phase velocity of the surface acoustic wave of the piezoelectric film is smaller than that of the nonpiezoelectric plate.

Surface acoustic wave transducer using a split-finger electrode on a

A surface acoustic wave device in which an X-cut LiTaO.sub.3 single crystal substrate has its one major surface coated with a SiO.sub.2 film and the direction of propagation of surface acoustic waves is selected between 80.degree. and 180.degree. measured from the Y-axis toward the Z-axis. The surface acoustic wave devices in accordance with the present invention has an extremely low temperature coefficient change and a high electro-mechanical coupling coefficient, exhibits a higher degree of both short- and long-term stability, and can suppress the generation of unwanted waves to a minimum or negligible degree.

Growing community of inventors

Neyagawa, Japan

Ritsuo Inaba