Abstract: A second display panel having a lower luminance is combined with a first display panel having a higher luminance, forming a combined display panel. The entire surface of the combined display panel is covered with a dimming filter for ornamental purpose. Transparency of the dimming filter is enhanced in a wave-length region of the light emitted from the second panel to alleviate a brightness imbalance between the first and second panels. The transparency is enhanced also in another wave-length region corresponding to light complementary to the light emitted from the second panel, so that a color shift of the display of the first panel is avoided. Preferably, an electroluminescent display panel which emits light having a sharp peak in a specific wave-length region is used as the second panel.

Abstract: A thin-film EL display panel which has excellent packageability, high reliability and stable performance characteristics, and which can prevent nonuniformity of brightness and color from occurring and a fabrication method thereof are provided. In the above thin-film EL display panel, two thin-film EL elements 1 and 2 formed by sequentially laminating first electrodes 12 and 22, first insulating layers, luminescent layers, second insulating layers and second electrodes 16 and 26 respectively on glass substrates 11 and 21 are laminated into position and connecting terminal portions 12a, 22a, 16a and 26a for connecting the first electrodes 12 and 22 and second electrodes 16 and 26 are formed on the edge portions of the substrates 11 and 21 of the thin-film EL elements 1 and 2.

Abstract: Disclosed is a method of producing an electroluminescent (EL) device having a CaGa2S4:Ce luminescent layer. The ratio of the X-ray diffraction peak intensity I2 for the (200) reflection of CaS to the X-ray diffraction peak intensity I1 for the (400) reflection of CaGa2S4 as appearing in the X-ray diffraction spectrum for the luminescent layer, I2/I1, is 0.1 or less. The amount of the impurity CaS in the luminescent layer is reduced. The EL device produces blue emission with high purity.

Abstract: A transparent display panel such as an electroluminescent panel is overlapped on a part of a conventional instrument panel for use in an automobile. The overlapped display panel displays additional information such as navigation maps when required and is turned off under a normal driving condition. When the overlapped transparent display panel is turned off, the conventional instrument panel displays information such as a vehicle speed, an engine speed and so forth. In this situation, overall luminance on the combined display panel is made uniform throughout a whole surface including the area where the transparent display panel is overlapped. To realize the uniformity of luminance, brightness of back lamps for illuminating the instrument panel is adjusted or a filter having an adequate transparency is used. The combined display panel may be also made by combining a non-transparent display panel with a conventional instrument panel.

Abstract: First and second insulating layers in an EL device are respectively composed of Al2O3/TiOx:Ba laminated layers. The Al2O3/TiOx:Ba laminated layers are formed by alternately laminating Al2O3 layers and TiO2 layers added with Ba by an ALE method. Adding Ba into the TiO2 layers mitigates a change in resistivity thereof with respect to a change in temperature. As a result, the EL device provides an excellent voltage withstanding performance which is stable against the changes in the temperature.

Abstract: In an EL device in which a blue light emitting material obtained by doping Ce as a luminescent center into CaGa.sub.X S.sub.Y host material is used for a luminescent layer, values of X and Y in the CaGa.sub.X S.sub.Y host material are set in ranges of 1.4.ltoreq.X.ltoreq.1.9, 2.9.ltoreq.Y.ltoreq.3.8. The blue light emitting material thus obtained has a new structure defined by the fact that an X-ray diffraction spectrum obtained by using Cu K.alpha. radiation as a X-ray source has at least one peak in diffraction angles of 13.5.+-.0.2 degree, 14.6.+-.0.2 degree and 25.7.+-.0.2 degree. The blue light emitting EL device has a luminance higher than that of a conventional EL device.

Abstract: A transparent display panel such as an electroluminescent panel is overlapped on a part of a conventional instrument panel for use in an automobile. The overlapped display panel displays additional information such as navigation maps when required and is turned off under a normal driving condition. When the overlapped transparent display panel is turned off, the conventional instrument panel displays information such as a vehicle speed, an engine speed so and so forth. In this situation, overall luminance on the combined display panel is made uniform throughout a whole surface including the area where the transparent display panel is overlapped. To realize the uniformity of luminance, brightness of back lamps for illuminating the instrument panel is adjusted or a filter having an adequate transparency is used. The combined display panel may be also made by combining a non-transparent display panel with a conventional instrument panel.

Abstract: In an electroluminescent element in which a first electrode, a first insulating layer, a luminescent layer, a second insulating layer and a second electrode are sequentially laminated on a substrate, the luminescent layer has a first and second luminescent portions which are located apart from each other. A color filter is provided above one of the first and second luminescent portions. The second electrode includes a first part electrode for activating the first luminescent portion and a second part electrode for activating the second luminescent portion. The color filter is formed so that a portion extending from a bottom face of the color filter is inserted into a gap between the first and second luminescent portions to surround an upper face and side faces of the one of the first and second luminescent portions.

Abstract: An electroluminescent device improved in brightness is disclosed. The electroluminescent device comprising sequentially stacked layers having an optically transparent material on at least the viewing side of the structure comprises a luminescent layer based on a Group II-III-VI compound host material with an element acting as a luminescent center added therein, wherein a Group II element having an ion radius differing from that of the Group II element constituting the compound host material is further added in the luminescent layer.

Abstract: A thin-film electroluminescent device includes dielectric layers having improved dielectric characteristics. The device is fabricated by forming a first transparent electrode layer of ITO, a first dielectric layer, a luminescent layer, a second dielectric layer, and a second transparent electrode layer of ITO in this order on an insulating substrate. Each of the two dielectric layers is a film constituted by TaSnON. That is, the film includes tantalum, tin, oxygen, and nitrogen.

Abstract: Fabrication of an electroluminescent device having a high-quality luminescent layer is disclosed. The device emits intense blue light. A first electrode layer, a first dielectric layer, the luminescent layer, a second dielectric layer, and a second electrode layer are successively formed on a glass substrate. At least the exit side of the device is made from an optically transparent material. A first gaseous source material of a group II element belonging to group II of the periodic table, a second gaseous source material of a group VIB element belonging to group VIB, and a third gaseous source material of an element forming the luminescent center of the luminescent layer are supplied into a reaction furnace through first, second, and third gas supply tubes, respectively, and caused to react with each other. Thus, the luminescent layer is formed by chemical vapor deposition. The first material acts as a base material from which the luminescent layer is formed.

Abstract: In an electroluminescent device comprising an insulating substrate having consecutively thereon a first electrode, a first insulating layer, a luminescent layer composed of two types or more luminescent portions differing in luminescent color which are provided in a flat panel arrangement to give a single-layered luminescent layer, a second insulating layer and a second electrode, a first dielectric film is disposed between the luminescent portions to provide an isolation layer for isolating the luminescent portions, and a second dielectric film for adjusting the luminescence threshold voltage is disposed on the light outcoupling side or on the side opposite thereto of one of said luminescent portions. Herein, the first and second dielectric films provided for isolating the luminescent portions and for adjusting the luminescence threshold voltage, respectively, are made of the same material and have a refractive index lower than that of both luminescent portions.

Abstract: A method and apparatus for manufacturing EL devices in a short period of time wherein during formation of a light emitting layer composed of II, III or VI-group of elements doped with a light emitting element through a chemical vapor deposition method, water content of a transport gas that transports gasified organic metals is removed through a dehydration filter and thus, source material decomposition due to the water content is prevented and a steady supply of source materials becomes possible. By removing the water content of the transport gas, source materials can be supplied constantly even if heating temperatures exceed a temperature conventionally regarded as the temperature at which decomposition starts and thus, a light emitting layer having a practical thickness can be formed in a short period of time. Because of the high-speed film formation, the rate of the film being contaminated with impurities lessens and the light emitting layer has a luminance three times that of conventional layers.

Abstract: A transparent thin-film EL display apparatus has a transparent thin-film EL element formed on a glass substrate. A rear substrate consisting of photochromic glass and the glass substrate on which the EL element is formed are disposed facing each other with the EL element located in between. A light-transmitting insulation material is inserted in a space between the two substrates and hermetically sealed. When the display on the EL element becomes hard to see due to light entering from the rear of the display apparatus, the photochromic glass reacts in response to the light and darkens the rear of the EL element, thereby blocking the light.

Abstract: An EL element having a color filter formed on an upper electrode thereof enables a decrease in the pixel loss or line defects. In the EL element, a lower transparent electrode, first insulating layer, luminescent layer and upper transparent electrode are laminated on a glass substrate. Further, a color filter is formed on the upper transparent electrode. As the color filter there is used a posi-resist having an average molecular weight in a range of from 100 to 50000 or a nega-resist having a polymerization reaction percentage in a range of from 5% to 70%.

Abstract: In an EL device in which a blue light emitting material obtained by doping Ce as a luminescent center into Ca.sub.X S.sub.Y host material is used for a luminescent layer, values of X and Y in the CaGa.sub.X S.sub.Y host material are set in ranges of 1.4.ltoreq.X.ltoreq.1.9, 2.9.ltoreq.Y.ltoreq.3.8. The blue light emitting material thus obtained has a new structure defined by the fact that an X-ray diffraction spectrum obtained by using Cu K.alpha. radiation as a X-ray source has at least one peak in diffraction angles of 13.5.+-.0.2 degrees, 14.6.+-.0.2 degrees and 25.7.+-.0.2 degrees. The blue light emitting EL device has a luminance higher than that of a conventional EL device.

Abstract: An electroluminescence element provided with a luminescent layer sandwiched between two electrodes on an insulating substrate. The luminescent layer is composed of zinc sulfide with a fluoride or a luminescent center element added, wherein the X-ray diffraction spectrum thereof has only a single peak at an X-ray diffraction angle from the luminescent layer, ranging from 25.degree. to 30.degree. according to a thin film X-ray diffraction measurement method using Cu-Kd radiation, and no other peaks of the X-ray diffraction spectrum exist at an X-ray diffraction angle of 27.degree..

Abstract: An electroluminescent element includes a glass substrate, on which are formed a first electrode, a first insulating layer, a first luminescent layer, a second luminescent layer, a second insulating layer, a second electrode, a protective film and a red color filter. In this structure, the first luminescent layer is made of ZnS having Mn added thereto, and the second luminescent layer is made of ZnS having Tb added thereto. Here, the clamp electric field intensity of the second luminescent layer is higher than that of the first luminescent layer, and the product of a dielectric constant and clamp electric field intensity of the first luminescent layer is larger than the product of a dielectric constant and clamp electric field intensity of the second luminescent layer. Consequently, it is possible to increase the luminance of light emitted from the luminescent layer and decrease the luminescence threshold voltage when the luminescent layer is made into a stacked layer structure.

Abstract: An electro-luminescent display apparatus which is capable of displaying two kinds of images is disclosed. The apparatus has a front and a rear electro-luminescent unit therein, and the green light emitted from the front unit directly displays the real image which looks close to a viewer while the orange light emitted from the rear unit is reflected by a reflector disposed at the back of the apparatus and displays a virtual image which looks far from the viewer. In order to reflect the light emitted backward from the front unit and the light emitted forward from the rear unit, reflecting electrodes are provided on the rear surface of the front unit or a reflecting film is disposed in the space between the front and the rear units.

Abstract: A luminescent layer in an EL device composed of CaGa.sub.2 S.sub.4 :Ce includes a first luminescent layer and a second luminescent layer. The first luminescent layer has an atomic ratio of Ga to Ca being higher than that in the second luminescent layer, and directly disposed on a first insulating layer, whereby delamination can be prevented. The atomic ratio of Ga to Ca in the second luminescent layer is approximately equal to a stoichiometric ratio, so that the threshold voltage of the EL device can be kept low.