Abstract: A displacement device with a first part (1) and a second part (3) which are mutually displaceable in a displacement direction. The first part (1) comprises a number of contact bodies (7) which are pressed against the second part (3) against a pretensioning force which is present between the first part (1) and the second part (3). The contact bodies (7) are movable stepwise relative to the first part (1) and are also displaceable perpendicularly to the displacement direction. A stepwise movement of the contact bodies (7) causes the first part (1) and the second part (3) to be displaced relative to one another in the displacement direction under the influence of a friction force present between the contact bodies (7) and the second part (3), while the first part (1) and the second part (3) are supported in an accurate position relative to one another perpendicular to the displacement direction through a displacement of the contact bodies (7) perpendicular to the displacement direction.

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: The invention relates to a method of manufacturing an optical component. In this method, a substrate, for example of glass, is successively provided with an orientation layer and an optically anisotropic layer of a material containing monomers which are provided with at least one covalently bonded reactive group, whereafter the optically anisotropic layer is polymerized. In accordance with the present invention, the applied orientation layer also comprises covalently bonded reactive groups. As a result, a good adhesion between the optically anisotropic layer and the orientation layer of the substrate is achieved. This has a favorable effect on the optical quality of the component. For the reactive groups use is preferably made of (meth)acrylate compounds which are polymerized by exposing them to radiation. Good results are achieved if for the orientation layer use is predominantly made of polyimide with covalently bonded reactive groups.

Abstract: A low-pressure mercury discharge lamp having emission maxima in three spectral regions, provided with a gastight, radiation-transmitting discharge vessel with a gas filling comprising mercury and rare gas. A luminescent layer comprises at least a first luminescent material with an emission maximum in the 590-630 nm region and a second luminescent material with an emission maximum in the 520-565 nm region. The first luminescent material contains a compound defined by the formulaM1.sub.x M2.sub.(1-x-y)BO.sub.3 : Eu.sup.+3.sub.y,in which M1 is selected from the group consisting of Sc, In and Lu, and M2 is selected from the group consisting of Sc, Y, La, Gd, Ga, In and Lu, in which M1 differs from M2, in which x.gtoreq.0 and 0.01.ltoreq.y.ltoreq.0.2, and in which the compound has the calcite lattice structure.

Abstract: A presentation system comprising an image projection screen and an overhead projector is described. The overhead projector comprises an illumination system, a support for supporting an image record carrier and a projection head for projecting the image present in the image record carrier on the image projection screen. The image projection screen is a polarizing screen which transmits radiation having a well-defined direction of transmission polarization, and the overhead projector is adapted to supply light having this direction of polarization. In this way, the quantity of radiation used for forming the image is considerably increased and substantially half the quantity of ambient light incident on the screen is suppressed, so that images having a considerably enhanced contrast and brightness are obtained.

Abstract: The invention relates to a printing form for a rotary relief-printing method, in which the printing dots transferring the printing ink constitute a half-tone screen and are superimposed by a relief structure constituted by indentations. Such printing forms are used, for example in flexographic printing methods for printing glass plates, for example display screens having a luminescent material coating. In the manufacture of these screens, the printing ink must be applied homogeneously and the ink dots appearing in the printed image must have a uniform border area. According to the invention, the printing form is to this end implemented in such a way that the relief structures are arranged homogeneously relative to the printing dots and, if the printing dots are periodically spread across the printing form, these relief structures are superimposed on the printing dots preferably with the same period.

Abstract: The invention relates to a method of selecting low-pressure mercury discharge lamps each provided with a discharge vessel which supports a luminescent layer on an inner surface, by which method the luminescent layer is excited and the low-pressure mercury discharge lamps are selected in dependence on the emission spectrum of the light radiated by the luminescent layer. The invention also relates to a device for selecting low-pressure mercury discharge lamps which are each provided with a discharge vessel supporting a luminescent layer on an inner surface, which device is provided with an excitation source for exciting the luminescent layers of the low-pressure mercury discharge lamps to be selected and with detection means for detecting the light radiated by the low-pressure mercury discharge lamps to be selected.

Abstract: A projection beam supplied by a projector is incident on a beam splitter in the form of a cholesteric filter. The cholesteric filter reflects circularly polarized radiation having a wavelength which corresponds to the pitch of the molecular helix and having a direction of rotation which corresponds to the direction of the molecular helix to a reflector. The circular direction of polarization reflected by the cholesteric filter is inverted on the reflector so that the beam is subsequently passed to the screen by the cholesteric filter.

Abstract: An electromechanical device has a coil configuration comprising an insulating substrate (30) carrying a first group of 12 series-connected spiral conductor patterns (21a-21m) and a second group of 12 series-connected spiral conductor patterns (22a-22m). Some of the conductor patterns (21a, 22a, 21d, 22d, 21e, 22e, 21i, 22i, 21j, 22j, 21m and 22m) are disposed on the upper side of the substrate (30). Other ones of the conductor patterns (21b, 22b, 21c, 22c, 21f, 22f, 21h, 22h, 21k, 22k, 21l and 22l) are disposed on the underside of the substrate (30). The conductor patterns on both sides of the substrate (30) are electrically interconnected by means of plated-through connections (40). The first group is in arranged in parallel with the second group by means of common connection electrodes (51 and 52). The conductor patterns (21a-21m) of the first group and the conductor patterns (22a-22m) of the second group are carried by the same substrate (30).

Abstract: The electric incandescent lamp has a quartz glass lamp vessel (1) or envelope (4') around the lamp vessel, which has a red coloured dope in the area at the side of the incandescent body (3). The quartz glass with red dope contains samarium.sup.II oxide, aluminium oxide, titanium dioxide, and silicon dioxide, the analysis of the glass in its oxidized form being Sm.sub.2 O.sub.3 1 to 3% by weight, Al.sub.2 O.sub.3 up to 3% by weight, TiO.sub.2, rest SiO.sub.2, the molar ratio Al/Sm being at least about 2 and the molar ratio Sm/Ti being from 2 to 8.

Abstract: In a self-oscillating power-supply circuit for charging a battery (B) the switching transistor (T2) is turned off if the voltage across the sensing resistor (R3) exceeds the threshold voltage of a zener diode (D5). Instead of the zener diode (D5) it is possible to use a switching transistor which is actuated when the current through the switching transistor exceeds a given value. A diode (D6) is arranged in series with the zener diode (D5) and can be short-circuited by means of a switch (T3) in order to switch the power-supply circuit from slow charging to rapid charging. A voltage sensor may be added to monitor the battery voltage and to eliminate the short-circuit of the diode (D6) when a given battery voltage is reached, as a result of which the power-supply circuit changes over to slow charging.

Abstract: The packaging sleeve has at a first end (4) thereof an extended (11) back wall (1) and extended (31) side walls (3) connected thereto. The sleeve is closed at the first end (4) by a lid (21) connected to the front wall (2) and provided with a closing flap (23) which extends into the sleeve and is kept enclosed by side flaps (33), which extend from the side walls (3) and which are overlapped by the closing flap (23). The extended (11, 31) walls (1, 3) prevent the closing flap (23) from being opened, unless the sleeve may be damaged or destructed.

Abstract: A light transmitting discharge vessel encloses a discharge space, sealed in a gas-tight manner, in which electrodes connected to current conductors which extend to the exterior are disposed. A filling in the discharge vessel comprises a rare gas, a buffer gas and at least one transition metal halide chosen from the halides of hafnium, zirconium and tantalum. Each of the electrodes comprises an electrode part containing a carbide chosen from the carbides of hafnium, zirconium and tantalum. As a result diffusion of transition metal from the plasma into the electrode is strongly suppressed so that the lamp keeps very good color rendering properties throughout its operation.

Abstract: An image projection apparatus comprises an illumination unit (10), an image display unit (20), comprising a matrix display panel (22) having a row and column array of pixels (25), a projection lens (40) for projecting range produced by the display panel on to a screen (50) and an optical deflection unit (30) arranged between the display unit and the projection lens which is operable selectively to shift the light rays from a row of pixels passing therethrough whereby the pixel row images on the screen in one field are displaced and interlaced with the pixel row images of a preceding field. The image display unit (20) includes an array of lens elements (60) overlying the array of pixels whose effect is to reduce the height of the image of each pixel row in the projected display so the pixel row images of one field can fill the gaps between adjacent pixel row images of a preceding field without any substantial overlap and display panels having high aperture ratio can be utilised.

Abstract: The cap (10) of the capped electric lamp (1) has a resilient member (14) which acts transversely to the axis (10') of the cap. This allows the lamp to be used in a lighting system having the lamp and a reflector (40), in which the reflector is of a simple construction. The resilient member (14) presses transverse reference locations (13) of the cap against flat mounting surfaces (50) in the reflector, which are located on the legs of a V. The cap (10), and thus the electric element (3) inside the lamp vessel (2), are as a result accurately positioned in the reflector in two directions transverse to the axis. The cap (10) may in addition have projections (23,24,25) distributed over its circumference, each having an axial reference location (12), by which the cap is axially aligned in the reflector (40) through cooperation with surfaces (49) ridge portions (46,47,48) of the reflector.

Abstract: A low-pressure discharge lamp of the invention is provided with a gas-tight discharge vessel (10) which contains an ionizable filling. Electrodes are arranged inside At least one of the electrodes has a tungsten coil (20.sub.A) which is electrically connected to current supply conductors (30.sub.A, 30.sub.A ') which extend to outside the discharge vessel (10). The coil (20.sub.A) has a central zone (21.sub.A) covered with an electron-emitting material (22.sub.A) and, on either side, boundary zones (23.sub.A, 23.sub.A ') between the central zone (21.sub.A) and respective current supply conductors (30.sub.A, 30.sub.A '). The boundary zones (23.sub.A, 23.sub.A ') having a covering (24.sub.A, 24.sub.A ') of a protective material, comprising a ceramic material having a specific resistance less than 1000 .mu..OMEGA..cm.

Abstract: An active matrix display device having an array of LC picture elements (12), with associated switching means (25), addressed in row sequential fashion via sets of row and column address lines (14, 16) includes in its drive circuit a data signal adjustment circuit (40) which adjusts data signals before application to the column lines (16) so as to compensate for anticipated effects of vertical and lateral forms of cross-talk due to stray capacitive couplings in the picture element array. A correction value for a picture element data signal is derived in the adjustment circuit (40) according to the values of data signals intended over a subsequent field period for other picture elements in the same column and one or both adjacent columns, and the relevant capacitive coupling factors. The display device may be of the type using TFTs, TFDs or a plasma-addressed display device.

Abstract: A display device in which an internal auxiliary voltage, which is used for controlling, is obtained via photovoltaic converter.

Abstract: A housing includes a hood having an opening which is closed by a lid having a lampholder fixed thereto so that the lampholder extends through an opening in a reflector fixed in the housing, and a lamp held by the lampholder is positioned in the reflector. Electrical connection is provided by a plug mounted to the lid and a socket mounted to the housing. The lid is releasable by means of arms which pivot in response to pulling a knob on the lid, whereby the lid and lampholder can be removed with one hand. The hood is hinged so that it can pivot only when the lid is removed.

Abstract: The high pressure discharge lamp has a quartz glass lamp vessel having two opposite pinch seals. The pinch seals have major faces which are tapering from an end face towards the discharge space and have raised ridges along their axial edges. The height of the ridges diminishes towards the end faces. The lamp vessel can be obtained from a cylindrical tube by pinching without prior processing.