摘要:
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.
摘要:
A light-emitting device (100) is disclosed. The light-emitting device (100) comprises a plurality of light-emitting elements (135) or light sources and a power module (120) adapted to selectively convey, supply or provide electrical power to the light-emitting elements (135). The power module (120) may be dimensioned such as to be able to power only a proper subset of the light-emitting elements (135) of the light-emitting device (100) at a given time, the subset having a maximum number of light-emitting elements (135) included therein with respect to the number of light-emitting elements (135) included in the all subsets of the light-emitting elements (135) of the light-emitting device (100). The plurality of sets of light-emitting elements (135) maybe arranged so as to emit light over a light emission area, and the plurality of sets of light-emitting elements (135) may be arranged relatively to each other such that different sets of light-emitting elements (135) emit light over different portions of the light emission area.
摘要:
The invention relates to a luminous window which can function both as a broad area light source and as a transparent window. The broad area light source is achieved by coupling light into a plate-shaped light guide, e.g. via the edges of the light guide, and extracting light from the light guide using geometric protrusions or diffraction gratings into a scattering layer which outputs the broad area light. The transparent window is achieved by switching the scattering layer into a non-scattering state, and possibly switching off the light source, so that light can propagate freely through the light guide and the scattering layer.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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. Due to such a construction of the PIN diode, the electrical field becomes substantially zero with reverse voltage in the proximity of the edge of the diode and hence ther sensitivity of a display arrangement according to the invention to ambient radiation, especially to the ambient radiation laterally incident on the diode, becomes considerably lower.
摘要:
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.