Matsushita Electric Industrial Co., Ltd.

Tsuneharu Nitta

Tomizo Matsuoka

Shigeru Hayakawa

Yosuke Fujita

Atsushi Abe

Ziro Terada

Jiro Terada

Takao Tohda

Fumio Fukushima

Yoji Fukuda

Jun Kuwata

Masahiro Nishikawa

Yukio Kasahara

Junichi Kato

Koichi Kugimiya

Hisahito Ogawa

Masamitsu Nishida

Koji Nomura

Hiromu Ouchi

Yoshihiro Matsuo

Yukihiko Ise

Fumio Hosomi

Yoichirou Yokotani

An electroluminescent display device comprising an electroluminescent emitting layer including zinc oxide containing a luminescent active material, an insulating layer formed on one surface of the electroluminescent emitting layer and a pair of energizing means for applying signal voltages corresponding to an information to be displayed to a multilayer assembly including the said two layers, characterized in that a plurality of semiconductor layers each containing at least one chemical compound selected from the group consisting of chemical compounds of the II-VI groups and tin oxide are arranged as one of the energizing means arranged on the side of the electroluminescent emitting layer or between the energizing means arranged on the side of the electroluminescent emitting layer and the electroluminescent emitting layer. This device features that it requires only a reduced drive voltage for image displaying purposes and ensures an increased luminescent brightness.

Electroluminescent display device

Electroluminescence display device containing a zinc sulfide emission

New black color insulator thin films comprising Pr oxide, composite oxides of Pr-Mn, Pr-Ni, Pr-Co or Mn oxide are used to constitute at least one part or all parts of interface film between a phosphor film and a back electrode film of an AC thin film EL panel; and the panel with such a high contrast as 5:1 even at an illumination of 400 lux has been obtained.

Thin film EL panel

An electroluminescent element, especially a thin-film electroluminescent element in which the dielectric film layer provided on at least one side of an electroluminor layer is essentially composed of the materials represented by the following compositional formula:

Thin-film electroluminescent element

The development of a dielectric thin-film which is high (140 MV/cm or above) in product of dielectric constant .epsilon..sub.i and dielectric breakdown field strength E.sub.ib is essential for realizing an EL element which can operate stably at a low voltage. Such dielectric film is also required which can withstand heat treatments at high temperatures above 500.degree. C. and is proof against clouding and in which the electrical breakdown caused by a minute fault produced in the process of film formation is self-healed. A film material which satisfies all of these requirements could be obtained from a TiO.sub.2 -BaO based composition by partially substituting the position of Ti with Sn, Zr or Hf and also partially substituting the position of Ba with Ca or Mg. By using these dielectric films, it is possible to obtain a low-voltage drive thin-film electroluminescent element which are high in production yield and reliability.

Thin film integrated device

A humidity sensitive device for sensing the humidity of an ambient humidity comprising a humidity sensitive resistor 15 which comprises as main component at least one selected from the group consisting of ZrO.sub.2, TiO.sub.2, Nb.sub.2 O.sub.5 and Ta.sub.2 O.sub.5 and an electric heater 13 applied near and for heating and retaining the humidity sensitive resistor 15 at a temperature above 200.degree. C. The humidity sensitive resistor 15 and a fixed resistor are series connected across an AC voltage source 17, and a voltage across the humidity sensitive resistor 15 or the fixed resistor 16 is rectified by a AC/DC converter and compared with a reference voltage by a comparator, thereby an output responding to humidity in the atmosphere can be measured for a wide range of temperature.

Humidity sensitive device

Plural number of thermo-plastic organic films having ceramic green layer(s) and a layer to become electrode thereon are laminated, thereby to form laminated body, which is hot-pressed to impregnate the organic film substance into the ceramic green layers and into layers to become electrodes, and then is fired; thereby, the ceramic layers are formed very thin, thereby producing a capacitor of large capacitance per volume.

Method for making multilayer ceramic body

Thin film electroluminescent element

A multi-functional sensing and measuring system capable of detecting both temperature and humidity is fabricated from a porous metal-oxide ceramic whose dielectric constant varies with temperature and whose electric resistance varies with ambient humidity. The sensing element is connected in series with a resistor and a rectangular pulse voltage is applied across the series combination, and the ambient temperature and humidity are measured simultaneously in terms of (i) the circuit time constant (to measure temperature) of a transient state value and (ii) the steady state value of the voltage across the resistor (to measure humidity).

Multi-functional sensing or measuring system

A ceramic luminescent device, in which a luminescent screen of zinc sulfide layer with luminescent impurities is formed on a translucent zinc oxide sintered body, and the luminescent light emitted from said luminescent screen is derived through said zinc oxide body. The device can be constructed in a manner that said luminescent screen is excited either by an electric field or electron beam.

Ceramic luminescent device

A multi-functional sensor capable of sensing the humidity and the concentration of reducing gases in the surrounding atmosphere with a single sensing element of p-type metal-oxide ceramic semiconductor is provided. When the ambient temperature is lower than 150.degree. C., the sensor can detect humidity in terms of variations in ion conduction due to the physical absorption of water by the sensing element, but when the ambient temperature or the temperature of the sensing element is at temperatures between 200.degree. and 600.degree. C., the sensor can detect the presence or concentration of reducing gases in the surrounding atmosphere in terms of variations in electron conduction due to the chemical absorption of gases by the sensing element.

Multi-functional sensor

Highly densed zinc sulfide ceramic materials, which essentially comprise zinc sulfide and alkali metals and/or alkaline earth metals and impurities acting as luminescent center, and which show a high brightness of cathode luminescence under irradiation of electron beam having a low energy, are easily made in the form of the sintered material, by heating the mixture of the said materials in inert or sulfuring atmosphere.

Zinc sulfide ceramic material and cathode ray tubes using the same

A ceramic sensor device is disclosed which comprises a sensing element of a ceramic material and electric conductors for connection to external circuit which are tightly embedded within a ceramic insulating body. The solid state sensor device having an excellent capability to withstand detrimental conditions such as a high temperature, rapid temperature change and mechanical shocks is provided. The sensor is advantageously used as a temperature sensor, a moisture sensor and a gas sensor for detecting oxidizing and reducing gas. Above all, the sensor is suited as a temperature sensor device for detecting temperature of exhaust gas purifying catalyst used in motor vehicles.

Growing community of inventors

Katano, Japan

Tsuneharu Nitta