Sharp Kabushiki Kaisha Corporation

Etsuo Mizukami

Yoshiharu Kanatani

Masahiro Ise

Hiroshi Kishishita

Yoshihiro Endo

Masashi Kawaguchi

Chuji Suzuki

Hisashi Uede

Kinichi Isaka

Yoshito Yamashita

Kenzoo Inazaki

Kenzoh Inazaki

Youzi Ohno

Yoshiaki Sato

Takaaki Horita

A glass substrate for supporting an electroluminescent (EL) display element comprising two dielectric layers defining a thin film EL layer, and two electrode layers, attached to each of the two dielectric layers is characterized by being composed of barosilicic acid without hydrolytic products thereon. A method for preparing such a glass substrate comprises the steps of preparing a glass substrate composed of borosilic acid, grinding a surface of the glass substrate, and cleaning the surface of the glass substrate without soaking it in an acidic solution, so that the glass substrate is free from formed hydrolytic products on the surface.

Substrate for thin film electroluminescent display panel

A thin-film electroluminescent (EL) display panel comprises a thin-film EL layer, first and second dielectric layers, the thin-film EL layer being disposed between the dielectric layers, first and second metal oxide layers, and first and second electrodes, the first and second metal oxide layers being disposed respectively between the first and second dielectric layers, and the first and second electrodes. Preferably, at least one of the first and second metal oxide layers is made of Al.sub.2 O.sub.3, SiO.sub.2 or the like with a thickness of about 100-800.ANG. and at least one of the dielectric layers being about 1000-3000.ANG..

Method for preparing a thin-film electroluminescent display panel

A fluid injection device that effectively injects fluid into an external circumfluid unit, for example, a thin-film EL panel requiring injection of moisture-proof oil. There is disclosed an extremely convenient fluid injection device that can repeatedly perform fluid injections without replacing the fluid injection pipe merely by pressing the fluid injection pipe against the fluid receiver part using a clip. The preferred embodiment uses such a clip freely mountable and removable, which elastically sandwiches a joint pipe by a flange portion and the fluid receiver part so that the opening in the tip portion of the fluid injection pipe can be tightly pressed against the fluid receiver part.

Fluid injection device for transmitting fluid

A thin electroluminescent (EL) display panel comprises an EL thin film unit for generating an EL light, a pair of glass substrates for sealing the EL thin film unit, a protective liquid within the cavity defined by the glass substrate for protecting the EL thin film unit, a pair of electrodes for conducting electric energy to the EL thin film unit, and a terminal connected to at least one of the pair of electrodes, the terminal comprising a metal such as Al, Al-Ni, Ag-Mn, etc., and the terminal being coupled to a power source.

Structure of thin electroluminescent display panel sealed by glass

A thin-film electroluminescent display panel is sealed by a pair of glass substrates for protecting itself from the environment. A protective liquid is introduced between a counter glass substrate and a substrate for supporting the electroluminescent display panel. The protective liquid comprises silicon oil or grease which assures the thin-film electroluminescent panel of preservation of the electroluminescent display panel. The counter glass substrate is bonded to the substrate through an adhesive of, for example, photocuring resin. A capillary tube is provided within the substrate for injecting the liquid under vacuum conditions. The counter glass substrate can be plate-shaped thereby eliminating a spacer. The liquid has the ability of spreading into pin holes generated on dielectric layers, and is resistant to high voltage, high humidity and high temperature, and is inert to layers constituting the thin-film electroluminescent display panel and has a small vapor pressure and a small coefficient of thermal expansion.

Thin-film electroluminescent display panel sealed by glass substrates

At least one silicon-oxynitride film is deposited on an electroluminescence layer for providing a uniform and stable dielectric layer for an electroluminescence display panel. The silicon-oxynitride film is deposited using a sputtering technique by mixing a small amount (1 mol%) of nitrous oxide (N.sub.2 O) gas into a sputtering gas such as nitrogen (N.sub.2) gas. Oxygen (O.sub.2) gas may be substituted for the N.sub.2 O gas mingled within the sputtering gas in the amount of five mol%. A target for sputtering is a pure silicon or sintered Si.sub.3 N.sub.4 plate. An R.F. discharge is provided so that the power flux density on the target becomes several to several ten W. The silicon-oxynitride film is derived by means of the reaction between ion sputtering and the sputtering gas. A dielectric layer is further provided for establishing high reliabiltiy high dielectric properties of the electroluminescence display panel, the dielectric layer being disposed together with the silicon-oxynitride film and being one of the group consisting of Al.sub.2 O.sub.3, SiO.sub.2, Ta.sub.2 O.sub.5, Si.sub.3 N.sub.4 and Y.sub.2 O.sub.3. The silicon-oxynitride flm which is injected by suitable ions such as P.sup.+, H.sup.+, He.sup.+, Ne.sup.+, or Ar.sup.+ may be further provided as the dielectric layer.

Oxygen atom containing film for a thin-film electroluminescent element

A coil is serially connected to a capacitive display unit, such as an EL display panel, which includes an insulating display element sandwiched between a pair of electrodes. The coil and the electrostatic capacitance of the display unit function, in combination, to form an LC resonance circuit, which limits transient current flowing through the insulating display element and enables the display unit to operate in a low power dissipation mode. An alternating driving signal to be applied to the display unit has an intermediate potential period on which a writing pulse is superimposed, thereby to minimize high voltage requirement of the writing circuit.

Control system for driving a capacitive display unit such as an EL

Disclosed is a photo-image memory panel composed of an electroluminescent element which exhibits electrical polarization effects upon light excitation. Under the conditions when the panel is biased by DC voltage or DC offset voltage, light irradiation is applied to the panel to establish a light-activated polarized electric field of which the intensity is controllable in dependence upon a photo-image desired to be written into the panel. Then, the photo-image written into the panel is held while maintaining the polarized electric field. Thereafter, application of a predetermined voltage pulse enables the reading out of the photo-image in the form of light emission. Alternatively, in case of an electroluminescent element of which the light emission versus applied voltage characteristics involve the hysteresis phenomenon, a train of alternating current pulses are employed as reading-out pulses to maintain light emission corresponding to the read-out image.

Photo-image memory panel and activating method therefor

Disclosed is a driving method for a thin-film electroluminescent element of a three-layer construction which emits light and exhibits the hysteresis phenomenon within the light emission versus applied voltage characteristics. The light intensity is maintained and memorized at a predetermined value in the element by the application of a train of sustaining pulses of alternating voltage, the amplitude thereof being chosen at the voltage level appearing at the point in the hysteresis loop characteristics where the difference between the maximum light brightness on the voltage decreasing curve and the minimum light brightness on the voltage increasing curve is considerably large. The sustaining light brightness is controlled by varying the amplitude or the pulse width of the sustaining pulses. The information may be written, memorized and eliminated in the EL element as variations of the light brightness. To write or eliminate the information in the EL element, it is also effective to utilize external light excitation.

Driving method for a thin-film electroluminescent element of a

Photo-image memory panel and activating method thereof

The present disclosure is directed toward a drive method and circuit for a memory matrix panel which comprises a light-emitting body having hysteresis behavior responsive to application of a desired AC voltage, a plurality of horizontal electrodes disposed on a first major surface of the light-emitting body and a plurality of vertical electrodes disposed on a second major surface of the light-emitting body, each cross point of the both electrodes providing a light-emitting unit point in a matrix array. A period of the applied AC voltage includes at least three sections wherein, prior to the writing, erasing or reading of information, a horizontal maintenance pulse having an amplitude necessary to maintain light emittance is applied to the plurality of horizontal electrodes during the first section thereof and a vertical maintenance pulse having an amplitude necessary to maintain light emittance is applied to the vertical electrodes during the second section thereof. In order to perform the writing, erasing or reading of information on a selected cross point, the vertical (or horizontal) electrode associated with such point receives an enable pulse having the shape identical with that of the horizontal maintenance pulse but the phase shifted into the third section, whereas the associated horizontal (or vertical) electrode receives write, erase or read out each having a predetermined amplitude necessary to perform the write, erase or read operation, the respective amplitude being superimposed on the enable pulse.

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Nara, Japan

Etsuo Mizukami