Abstract: An alternating current thin-film electroluminescent device includes a plurality of pixel electrodes. An electroluminescent phosphor material is located between a first dielectric layer and a second dielectric layer. A transparent electrode layer, wherein at least a portion of the electroluminescent phosphor material and the first and second dielectric layers are located between the pixel electrodes and the transparent electrode layer. The first dielectric layer is closer to the transparent electrode layer than the second dielectric layer. The phosphor material is patterned.

Abstract: The present invention concerns an insulating film of a thin film structure deposited on an essentially alkali metal-free glass substrate, comprising alternating layers of aluminium oxide and titanium oxide and thin film electriluminescent device wherein said insulating film is incorporated as an insulating layer between the phosphor layer and the electrode layers. In the insulating film, the ratio between the cumulative thicknesses of said titanium oxide and said aluminium oxide is less than 0.75, and due to the ratio lower than that of prior art, good resistance against cracking of the film is obtained.

Abstract: A thin film electroluminescent device has a bottom substrate and a first electrode layer deposited on the bottom substrate. The first insulating layer is deposited on the first electrode layer. A phosphor layer is deposited on the first insulating layer. A second insulating layer is deposited on the phosphor layer. A second electrode layer is deposited on the second insulating layer. In one aspect of the invention, at least a portion of the first insulating layer includes a layer of aluminum titanium oxide, and at least a portion of the second insulating layer includes a layer of a fusing dielectric material. In another aspect of the invention, the first insulating layer includes a layer of a refractory metal oxide, and the second insulating layer includes a layer of a fusing dielectric material.

Abstract: A normally white twisted nematic liquid crystal display (LCD) includes a liquid crystal layer for twisting at least one normally incident wavelength of visible light when in the off-state. Front and rear orientation layers sandwich the liquid crystal layer therebetween with the front orientation layer causing a front liquid crystal tilt sense direction AF and the rear orientation layer causing a rear liquid crystal tilt sense direction AR different than the direction AF. Rear and front tilted retardation layers are located on opposite sides of said liquid crystal layer. Each of the rear and front tilted retardation layers has an optical axis defining an azimuthal angle &phgr;, and a tilt angle &thgr;, where at least the tilt angle &thgr; varies through the thickness of the layer.

Abstract: The system illuminates an active matrix EL device (AMEL) to provide a gray scale display. The device includes a first electrode layer comprising an active matrix of individually addressable pixel electrodes, a second electrode layer, and a thin film EL laminate stack including at least an EL phosphor layer and a dielectric layer. The stack is disposed between the first and second electrode layers. A first group of selected ones of the pixel electrodes are addressed with data signals during a first subframe time period where the first group includes fewer than all of the pixels electrodes of the display. The second electrode layer is driven during the first subframe time period with a first illumination signal. A second group of selected ones of the pixel electrodes are addressed with data signals during a second subframe time period where the second group includes at least one pixel electrode not included within the first group.

Abstract: The present invention concerns a method of growing a cerium-doped SrS phosphor layer by the Atomic Layer Epitaxy-method. According to the invention an organometallic cerium compound containing at least one cyclopentadienyl type ligand is used as a precursor for the dopant cerium. The cyclopentadienyl type cerium compounds can be used as ALE precursors at about 400° C. substrate temperatures without any observable thermal decomposition during processing.

Abstract: A light emitting phosphor having improved luminance is incorporated into an ACTFEL device which includes a phosphor layer having the formula MIIS:Cu,Ag where MII is taken from the group calcium, strontium, barium and magnesium, S is sulfur, Cu is copper, and Ag is silver.

Abstract: The luminance of a phosphor suitable for an alternating current thin-film electroluminescent device is substantially improved according to the present invention by including an alkali halide. The alkali halide included within the bulk of the phosphor material results in providing a significant number of trapping states which trap free electrons within the phosphor material. The addition of the trapping states (added defects) within the bulk tend to control the electrical and optical characteristics of the phosphor material. This reduces asymmetric light output characteristics of traditional phosphor material, reduces asymmetric current movement within the phosphor material, and decreases the influence of the interfaces between the phosphor material and insulating materials resulting in decreased aging and increased brightness.

Abstract: A full color active matrix electroluminescent display includes an active matrix of pixel electrodes, a broad spectrum electroluminescent phosphor stack placed atop the active matrix of pixel electrodes and a transparent electrode placed atop the electroluminescent phosphor stack. A liquid crystal color shutter device is placed atop the transparent electrode for selectively filtering light from the electroluminescent phosphor stack selectively permitting the transmission of red, green or blue colored light in response to commands from a synchronizing circuit that synchronizes the operation of the shutter with the illumination of selected pixels in the active matrix display. Performance is further enhanced by the use of a double notch filter for the white light emitting broad spectrum electroluminescent phosphor so as to provide it with a uniform response at all waves lengths of interest.

Abstract: A light emitting phosphor having improved luminance is incorporated into an ACTFEL device having front and rear electrode sets, a pair of insulators sandwiched between the front and rear electrode sets, and a thin film electroluminescent laminar stack which includes a phosphor layer having the formula M.sup.II S:D,H,F where M.sup.II is taken from the group calcium, strontium, barium, and magnesium, S=sulfur, D is taken from the group copper, lead, gold, silver, magnesium, antimony, bismuth and arsenic, H is taken from the group fluorine, chlorine, bromine, and iodine, and F is taken from the group gallium, indium, aluminum, germanium, silicon, lanthanum, scandium, and yttrium. Deep blue and green chromaticity phosphors may be obtained through selection of multiple co-dopants and adjusting their relative concentrations.

Abstract: An active matrix electroluminescent device that includes a plurality of layers. A rearwardly disposed support layer supports the plurality of layers and an interface circuit. The interface circuit is electrically connected to row and column drivers by a plurality of first electrical lines. The drivers are electrically connected to the plurality of layers so as to enable pixels within the electroluminescent device to be selected. An interface controller is remotely located from the support layer and is electrically connected to the interface circuit by at least one second electrical line so as to indicate which pixels within the device to illuminate. The number of first electrical lines is greater than the number of the at least one second electrical line. In another embodiment of the present invention, the number of lines required to interconnect a passive thin film electroluminescent device with an interface controller can in a similar manner be reduced by including an interface circuit.

Abstract: Energizing an active matrix electroluminescent device with a generally sinusoidal illumination waveform causes the electroluminescent layer to emit light. A sinusoidal waveform minimizes the peak currents reducing the likelihood of burnouts and decreases the imposed voltages on the data lines increasing the likelihood that the high voltage transistors will function as intended. Preferably, the sinusoidal waveform is generated by using a single 12 volt power source which reduces the expense, weight and bulk of the electroluminescent device. The 12 volt power source may be used to operate an operational amplifier that receives a small sinusoidal input signal and produces a low voltage generally sinusoidal waveform that is amplified by a step-up transformer for energizing the transparent electrode layer of the device so as to cause the electroluminescent layer to emit light.

Abstract: An active matrix electroluminescent device includes a plurality of layers including at least a transparent electrode layer, a circuit layer including a plurality of first electrical traces, and at least two layers including an electroluminescent layer and a dielectric layer. The at least two layers are disposed between the circuit layer and the transparent electrode layer so as to emit light upon the application of an electric field. The plurality of layers are supported by a support layer. An elongate cable includes a plurality of second electrical traces supported thereon. In a first aspect of the present invention the cable is supported by the support layer and a plurality of electrical conductors electrically interconnecting respective ones of the first traces with the second traces. The electrical signals transmitted from respective ones of the second traces to the first traces permit selection of individual pixels within the device.

Abstract: A full color TFEL display includes stacked panels emitting blue and a combination of red and green light. The panel nearest the viewer employs transparent electrodes on both sides and an insulator bridge structure for the scanning electrodes that alleviates the effect of pinhole defects. The panel farthest from the viewer employs transparent-top electrodes. Each row electrode on the scanning side includes an insulator bridge extending across the panel and then ITO pads extending laterally of the bridge onto the EL stack to form sub pixel points. A bus bar connects all the pixel pads in a row and provides the scanning voltage. The insulator bridge prevents the bus bars from shorting out and permits the pixel pads to fuse open in the event of a short circuit.

Abstract: A construction for an electroluminescent display device comprises an electroluminescent element stack having an outer edge and including a light emitting electroluminescent panel, an electronic circuit board, and a connector electrically coupling the electronic circuit board to the electroluminescent panel. A frame member of generally U-shaped cross-section fits over and compresses the electroluminescent element stack along the outer edge. Additionally, a method of constructing an electroluminescent display device comprises the steps of forming an electroluminescent element stack having a light emitting panel, an electronic circuit board and a connector coupling the electronic circuit board to the electroluminescent panel. The electroluminescent element stack is formed to have an outer edge. A frame member is formed to have generally U-shaped cross-section and resilient arms.

Abstract: A method of illuminating an active matrix EL device (AMEL) to provide a gray scale display. The device comprises a first electrode layer comprising an active matrix of individually adjustable pixel electrodes, a second electrode layer, and a thin film EL laminate stack including at least an EL phosphor layer and a dielectric layer, and the stack being disposed between the first and second electrode layers. The gray scale display is illuminated by the steps of, energizing a first set of selected ones of the pixel electrodes with data signals during a first subframe time period. Selected pixels are illuminated by driving the second electrode layer during the first subframe time period a first illuminating signal having predetermined characteristics including frequency, amplitude, wave shape and time duration. Thereafter, a second set of selected ones of the pixel electrodes are energized with data signals during a next subframe time period.

Abstract: A construction for electroluminescent device includes a substrate and an electroluminescent stack which forms a step relative to the substrate. A transparent layer of protective material is placed atop the stack to bridge the step and create a smooth edge profile along the edge. A metallization layer is situated atop the layer of protective material and is coupled to the electroluminescent stack through vias in the protective material.

Abstract: An AC thin film electroluminescent (TFEL) device includes a multilayer phosphor for emitting white light having improved emission intensity in the blue region of the spectrum. The multilayer stack consists of an inverted structure thin film stack having a red light emitting manganese doped zinc sulfide (ZnS:Mn) layer disposed on a first insulating layer; a blue-green light emitting cerium doped strontium sulfide (SrS:Ce) layer disposed on the red light emitting layer; and a blue light emitting cerium activated thiogallate phosphor (Sr.sub.x Ca.sub.1-x Ga.sub.2 S.sub.4 :Ce) layer disposed on the blue-green light emitting layer. The manganese doped zinc sulfide layer acts as a nucleating layer that lowers the threshold voltage, and the cerium activated thiogallate phosphor layer provides a moisture barrier for the hydroscopic cerium doped strontium sulfide layer. The white light from the multilayer phosphor can be appropriately filtered to produce any desired color.

Abstract: A TFEL structure is disclosed that includes first and second electrode layers sandwiching a TFEL stack including at least one insulator layer and a novel three layer laminate structure. The three-layer laminate structure includes an alkaline earth thiogallate phosphor layer, a nucleating layer and an injection layer. The nucleating layer lies between the phosphor layer and the injection layer. The injection layer provides a charge injection function through the nucleating layer for the thiogallate phosphor layer which is of high crystallinity at its interface with the nucleating layer. A preferred injection layer includes indium, for example as the metal or as indium tin oxide. The best material for the nucleating layer is zinc sulfide.

Abstract: A multi-source reactive deposition process for preparing a phosphor layer for an AC TFEL device having the chemical formula M.sup.II M.sup.III.sub.2 X.sub.4 :RE, where M.sup.II is a group II metal taken from the group magnesium, calcium, strontium and barium, M.sup.III is a group III metal taken from the group aluminum, gallium and indium, X is taken from the group sulfur and selenium, and RE comprises a rare earth activator dopant taken from the group cerium and europium is disclosed. The phosphor film is formed in crystalline form on a substrate heated to a temperature between 400.degree. and 800.degree. C. by depositing more than one deposition source chemical where at least one of the deposition source chemicals of the group II metal or the group III metal is a compound.