Abstract: An image display apparatus (100) comprises: a display device (104) for displaying an image 900 by emission of display light (210) in a first direction; a scattering layer (902) disposed in front of the display device (104), for scattering at least a portion of ambient light (208); a transparent plate-shaped light source (950), arranged parallel to the scattering layer (902) and being optically coupled to the scattering layer (902). The plate-shaped light source (950) may be a passive light source, in which case at least one light source (967) is arranged along an edge of the plate-shaped light source (950). When the display device (104) is ON, the scattering layer (902) and the plate-shaped light source (950) are transparent. When the display device (104) is OFF, the scattering layer (902) is scattering and the plate-shaped light source (950) is ON.

Abstract: The display panel (21) comprises a light guide (2), a second plate (4) and a movable element (3) between both plates for locally decoupling light out of the light guide (2). Voltages, applied to electrodes (5,6 resp. 25), associated with the light guide (2), the second plate (4) and the movable element (3), locally bring the movable element (3) into 5 contact with the light guide plate (2) or the second plate (4). If, between the light guide (2) and the first electrodes (5) a layer (51) is present with a second refractive index being smaller than the first refractive index of the light guide (2), and the light guide (2) is positioned between the first electrodes (5) and the movable element (3), absorption of the light transported through the light guide plate (2) is reduced, providing a display panel (21) with 10 improved power efficiency.

Abstract: A flat panel display apparatus comprises plasma discharge cells, which formed between a first base plate (2a) and a second base plate (1a). The first base plate (2a) has pairs of sustain electrodes (2b, 2c), and a second base plate (1a) has data electrodes (1b). Between said electrodes (2b, 2c, 1b) discharge volumes are formed. The device further has a drive circuit which comprises a circuit for providing data to the discharge cells. The display device comprises a conductive layer (51, 72, 91, 101) on the first (2a) or second substrate (1a) for both of a pair of sustain electrodes (2b, 2c). Said conductive layer (51, 72, 91, 101) extends outside the discharge volume (4) and forms an internal capacitance (Cpar) in the display device which capacitance is in parallel to the capacitance formed in operation by the pair of sustain electrodes and the discharge.

Abstract: A matrix display comprises a matrix of optically addressable pixels (Pij). The pixels (Pij) comprise a light sensitive element (LSij) having a state depending on a brightness of control light (Lj) impinging on it. The pixels (Pij) further comprise a pixel light generating element (LGij) for generating pixel light (LMij) with a brightness depending on the state of the light sensitive element (LSij). The matrix display device comprises a sheet of transparent material (TS) positioned in front of the matrix of pixels (Pij), and a light source (LS) which couples source light into a side of the sheet of transparent material (TS). In use, the source light is substantially totally internally reflected in said sheet (TS). The control light (Lj) leaves the sheet (TS) at positions where the sheet (TS) is locally disturbed. This control light switches or changes the brightness of the pixels (Pij) at these positions, or provides touch position information.

Abstract: Plasma display panel in which the fluorescent layer, a dielectric layer having a high relative dielectric constant, is provided between the electrodes and the phosphor(s). This improve the efficacy of the device and lowers minimum sustain voltage and firing voltages.

Abstract: A plasma picture screen is provided with a front plate, which comprises a glass plate on which a dielectric layer and a protective layer are provided, with a carrier plate provided with a phosphor layer comprising a red and a blue phosphor as well as a green, Tb3+-activated phosphor, with a ribbed structure that subdivides the space between the front plate and the carrier plate into plasma cells filled with a gas comprising xenon, and with one or several electrode arrays on the front plate and the carrier plate for generating corona discharges in the plasma cells. The gas comprises xenon in a proportion of between 5 and 30% by volume.

Abstract: Plasma display panel in which the fluorescent layer comprises non-saturating green phosphor(s). This improves the efficacy of UV-light generation and allows the use of higher sustain voltages, leading to further improvement of the efficacy and luminance. The display panel may include driver means for sustaining a generated plasma with a sustain voltage whose peak to peak voltage is at least 400V. This can be combined with existing red and blue phosphor to obtain a desired color.

Abstract: In a plasma display or a field emission display, sub-pixels having extra (non-saturating) phosphors are applied to enhance the efficacy. Depending on the luminance and color of a pixel to be displayed, driving of the most efficient combination of sub-pixels is performed.

Abstract: The invention relates to a plasma picture screen with an improved color saturation and an improved color constancy. This is achieved through the use of Tb3+-activated phosphors and a gas mixture with an increased xenon content.

Abstract: Plasma display panel in which the fluorescent layer comprises non-saturating green phosphor(s). This improves the efficacy of UV-light generation and allows the use of higher sustain voltages, leading to further improvement of the efficacy and luminance.

Abstract: The invention relates to an erasable non-volatile memory in which a diode is formed at each point of intersection between the x-selection lines (Ki) and y-selection lines (Rj), of which diode the anode and cathode are conductively connected to the x- and y-selection lines. The diodes are formed in hydrogenated amorphous silicon or silicon compounds such as amorphous Si−xGex. Writing takes place by means of a current pulse through selected diodes. The current in the forward direction becomes much lower, for example a few hundred times lower, than in diodes which are not selected, probably owing to degradation in the semiconductor material. The diodes may be returned to their original state again (i.e. be erased) through heating, for example at a temperature of 200° C. during 100 minutes. Preferably, the diodes are formed by Schottky diodes because the characteristic in the reverse direction does not (substantially) change in this type of diode.

Abstract: Plasma display panel in which the fluorescent layer comprises non-saturating green phosphor(s). This improves the efficacy of UV-light generation and allows the use of higher sustain voltages, leading to further improvement of the efficacy and luminance. The display panel may include drive means for sustaining a generated plasma with a sustain voltage whose peak-to-peak voltage is a least 400 V. This can be combined with existing red and blue phosphor to obtain a desired color.

Abstract: Thin-film switching elements (20,21) of a display device or the like include a first electrode (22,23) on a substrate (11) and a layer of switching material (24,25) on the first electrode. These switching elements may be semiconductor PIN or Schottky diodes, or MIMs, or TFTs. The switching material is typically .alpha.-Si:H in the case of the semiconductor diodes and TFTs, and tantalum oxide or silicon nitride in the case of the MIMs. An auxiliary layer (28,29) of insulating material is provided between the first electrode (22,23) and the layer of switching material (24,25), leaving an edge (30,31) of the first electrode uncovered, so that the layer of switching material is connected to this edge only. The switching elements with this construction can be patterned using an inexpensive proximity printer, and have a low capacitance value, so counter-acting kickback and crosstalk which can occur in a switching matrix, e.g in the display of television pictures.

Abstract: A display device which is based on a number of pixels (2) which are arranged in rows and columns, each pixel having a two-pole switching element (3) between an electrode (13) of a pixel and a row electrode (5), and a second two-pole switching element (23) between said electrode of the pixel and an auxiliary row electrode (25) used for resetting, auxiliary row electrodes for resetting having a common connection (24) for a plurality of rows of pixels.

Abstract: For satisfactory operation of a display arrangement having an electro-optical display medium and picture elements arranged between row and column electrodes and connected in series with an anti-parallel arrangement of PIN diodes, the diodes should have a small reverse current notwithstanding any ambient radiation present. In a display arrangement according to the invention, a small photo-current in the reverse direction is obtained due to the fact that the i-region and the p- or n-type region do not adjoin each other directly in the proximity of the edge of the mesa-shaped PIN diode. The region within which the aforementionhed regions adjoin each other is preferably located at a distance from the edge of the mesa-shaped PIN diode amounting to at least once the penetration depth of the ambient radiation plus the diffusion length of charge carriers in the i-region.

Abstract: Method of preparing an aluminum oxide containing quartz glass activated by bivalent europium and comprising as glass matrix oxides mainly SiO.sub.2 and furthermore per mol of SiO.sub.2 up to at most 0.15 mol of at least one of the oxides, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, P.sub.2 O.sub.5, ZrO.sub.2, Scf.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, Gd.sub.2 O.sub.3, Lu.sub.2 O.sub.3, the alkali metal oxides and the alkaline earth metal oxides. A mixture is made of the composite oxides or of compounds which yield these oxides. The mixture comprises europium in the form of an aluminum containing compound of bivalent europium. The mixture is melted at a high temperature in a reducing atmosphere and is then cooled. The luminescent quartz glasses obtained are used in luminescent screens of, for example, low-pressure mercury vapor discharge lamps.

Abstract: Luminescent alumino-silicate and/or alumino-borate glass comprising lanthanum and/or gadolinium and activated by Tb.sup.3+ and/or Ce.sup.3+ and have a composition comprising 35-85 mol % of SiO.sub.2 and/or B.sub.2 O.sub.3, 1-35 mol % of La.sub.2 O.sub.3 and/or Gd.sub.2 O.sub.3, 5-45 mol % of Al.sub.2 O.sub.3 and 0.5-30 mol % of Tb.sub.2 O.sub.3 and/or Ce.sub.2 O.sub.3. The La.sub.2 O.sub.3 and/or Gd.sub.2 O.sub.3 may be replaced up to not more than 50 mol % by Y.sub.2 O.sub.3, Sc.sub.2 O.sub.3, Lu.sub.2 O.sub.3, ZrO.sub.2, P.sub.2 O.sub.5 and/or alkaline earth metal oxides. The glass can be used in a luminescent screen, for example, of a low-pressure mercury vapour discharge lamp.

Abstract: Luminescent quartz glass comprising as a glass matrix oxide mainly SiO.sub.2 and furthermore per mole of SiO.sub.2 from 0 to 0.15 mol of at least one of the oxides Al.sub.2 O.sub.3, B.sub.2 O.sub.3, P.sub.2 O.sub.5, ZrO.sub.2, Sc.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, Gd.sub.2 O.sub.3, Lu.sub.2 O.sub.3, the alkali metal oxides and the alkaline earth metal oxides. The glass comprises as an activator oxide at least one of the oxides Tb.sub.2 O.sub.3 and Ce.sub.2 O.sub.3 in a quantity of 0.75 to 15 mol % calculated with respect to the glass matrix oxides. In one embodiment the glass comprises Tb.sub.2 O.sub.3 and also not more than 0.2 mol % of Eu.sub.2 O.sub.3 as an activator oxide. The glasses are preferably obtained by a sol-gel technique and are useful, for example, in luminescent screen of low-pressure mercury vapor discharge lamps.