Abstract: A lighting unit includes a discharge vessel having a wall provided with a first luminescent layer, a gas fill consisting essentially of neon at a pressure less than 30 mbar, and a means for providing a constant DC current for exciting the fill in the discharge vessel to emit UV light for exciting the luminescent layer. DC operation offers substantially higher luminous flux over AC operation. The lighting unit may further include a housing having a reflective surface, a second luminescent layer, and a filter incorporated within the discharge vessel.

Abstract: An electric incandescent lamp has a filament having two incandescent portions interconnected by an intermediate non-lightemitting conductor. The filament is accommodated in a single ended, pinchsealed tubular glass envelope and is supported therein in that the intermediate conductor is embedded in an inner portion of a second pinch seal. The lamp has means to lower the temperature of the intermediate conductor and thereby of the second pinch, if the maximum permissible temperature of the latter would otherwise be exceeded.

Abstract: An optical device for combining three sub-beams of different colors to one color beam is disclosed having a first and a second color-selective reflector arranged on transparent plate-shaped substrates, the first reflector reflecting a first of said sub-beams, the second reflector reflecting the first sub-beam and a second of said sub-beams and a third of said sub-beams passing through the second reflector and its substrate. A transparent plate is arranged in the path of the first sub-beam and in front of the first reflector, the transparent plate having a product of refractive index and thickness equal to that of the substrates of the first and second reflectors. An astigmatism correcting element is positioned in the path of the color beam.

Abstract: A low-pressure mercury discharge lamp is provided with a light-transmitting discharge vessel (10) which contains mercury and a rare gas and which comprises means (20) for maintaining an electric discharge in the discharge vessel. A metal holder (30) supporting an amalgam (31) is arranged in the discharge vessel. The holder (30) is a metal plate (33) bent about an axis (32), portions (34a, 34b) of the plate bent towards one another defining a slot (35), while the holder is pinched together at its ends (36) and the amalgam (31) coats the holder on an internal surface (37) thereof. The manufacture of the holder is simple.

Abstract: The invention relates to a high-pressure discharge lamp provided with a discharge vessel which is enclosed with intervening space by an outer bulb with a lamp cap, which lamp also comprises an UV-enhancer having a wall and an internal electrode and arranged in the space between outer bulb and discharge vessel.According to the invention, the wall of the UV-enhancer is made from ceramic material.The invention offers the advantage that the lamp ignites reliably at a comparatively low ignition voltage of 3 kV already.

Abstract: An active matrix display device, having an array of picture elements (12) comprising electro-optic, for example LC, display elements (14) and associated switching devices (15), for example thin film diodes, driven by selection and data signals applied to sets of row and column address conductors (16, 17) respectively, which includes a reference circuit (34) comprising a switching device (35) connected to a capacitive element (36) and similarly driven periodically by selection signals and a reference data signal applied via one of the column address conductors (17), and an adjustment circuit which senses the voltage at the capacitive element (36), indicative of the operational behavior of the switching device (35), at particular times corresponding substantially to the termination of a selection signal applied to the reference circuit and which, according to the sensed voltage at that time, is operable to adjust the drive voltages used for the picture elements (12) so as to compensate for changes in the operat

Abstract: A metal halide lamp provided with an outer bulb having a volume V.sub.bu in which a discharge vessel with a volume V.sub.ob and having a ceramic wall is arranged, which vessel contains mercury, at least one halide, and also a rare gas having a filling pressure P.sub.ob. The relation P.sub.ob *V.sub.ob /V.sub.bu .ltoreq.6 mbar is satisfied.

Abstract: A pair of lamp holders (5) and a pair of contact members (20) for mechanically and electrically mounting a double ended electric lamp (50) transversely to the optical axis (4) of reflector means (3) present in the housing (1). The contact members (20) each have a first body (21) with an electric contact (23) and a second body (22) to cooperate to keep a current lead (51) of the electric lamp (50) against the contact (23). The first (21) and the second body (22) have a hinging connection (24) one with the other, and a lock (25) at a distance therefrom for keeping them pressed one against the other. In an embodiment the housing (1) has a door (6) hingingly connected to a major part (1') of the housing. In this embodiment the hinge (24) and the lock (25) of the housing (1) act a the hinge (24) and the lock (25) of the contact members (20). The luminaire provides for an easy, fast and secure electrical connection of a lamp.

Abstract: An electrodeless low-pressure discharge lamp according to the invention is provided with a lamp vessel which is closed in a gastight manner and which has an ionizable filling. The lamp vessel has an end portion with a cavity in which an electric coil is accommodated. The cavity further contains a heat conductor which extends to outside the cavity and has a flange there with an axis, a circumference, a surface which faces away from the lamp vessel and a surface which faces the lamp vessel. A mounting member is connected to the lamp vessel and fastened against the flange. The mounting member is provided with at least one hook which points radially inwards and which cooperates with a recess in the surface of the flange which faces away from the lamp vessel. The recess issues into an axial groove at the circumference of the flange extending into the surface facing the lamp vessel. This construction renders possible a quick assembly of the mounting member with the flange.

Abstract: A generator comprises a lamp (1), an optical unit (2-3) which concentrates the light around an axial image point (5), a ferrule for an optical-fiber bundle, comprising a cylindrical part (7) which, on the one hand, retains the end of the optical-fiber bundle and, on the other hand, surrounds a transparent rod (12) which is brought into contact with the end of the optical-fiber bundle. The end of the transparent rod (12) facing the optical unit and the lamp has a concave surface, the axial image point (5) around which said optical unit concentrates the light is a virtual image point situated inside said rod, and the end of the fiber bundle (6) is polished and brought into contact with the transparent rod (12) by any suitable mechanical means.

Abstract: An apparatus has a display (D) on which the signs which appear on the display during a cycle of use of the apparatus are displayed in an accelerated manner in a demonstration mode.

Abstract: A discharge vessel (10) closed in a gastight manner has a cavity (11) enclosing a discharge space provided with an ionizable filling. A coil (20) with a winding (21) of an electric conductor and an assembly (30) of a heat conductor (31) and one or several elongate cores (32) of soft-magnetic material are accommodated in the cavity. The cores (32) are arranged along a longitudinal axis (33) of the heat conductor (31) in one or several recesses (34) of the heat conductor which issue into a circumferential surface (36) of the assembly (30). The heat conductor (31) occupies at least half the circumference in a cross-section perpendicular to the longitudinal axis (33) of the assembly (30). The construction of the lamp according to the invention renders possible lamp operation at higher lamp powers also without the use of a heat pipe.

Abstract: A low-pressure mercury vapor discharge lamp according to the invention is provided with a discharge vessel having a tubular portion and a first and a second end portion. The discharge vessel encloses a discharge space provided with a filling of mercury and a rare gas in a gastight manner. Each end portion supports an electrode which is arranged in the discharge space. Current supply conductors extend from the electrodes through the end portions to outside the discharge vessel. The tubular portion of the discharge vessel is provided with a metal oxide layer on a surface which faces the discharge space. The first and the second end portion are also provided with metal oxide layers at surfaces which face the discharge space. The lamp according to the invention has a comparatively low mercury consumption.

Abstract: Picture display device (1) comprising an illumination system (3) provided with a light source (5) for generating a light beam. The device (1) also comprises a picture display panel (9) having a matrix of pixels (10) for modulating said light beam in conformity with picture information to be displayed. A first microlens array (13) having a plurality of first lenses (15) and a pitch .DELTA.w.sub.1 is present between the illumination system (3) and the picture display panel 9. A second microlens array (17) having a plurality of second lenses (19) and a pitch .DELTA.w.sub.2 is present between the first microlens array (13) and the picture display panel (9). The focal planes of the two microlens arrays coincide and .DELTA.w.sub.1 =.DELTA.w.sub.2 =.DELTA..sub.w applies to the pitches. The first lenses (15) have dimensions which are substantially equal to the dimensions of the second lenses (19).

Abstract: The high pressure discharge lamp has electrodes which each have a wrapping of tungsten wire near the tip of the electrode rod. The electrode rod has unround cross-sections, formed by indentations and bulges. The tungsten wire, wrapped around the electrode rod, is in substantially circumferential contact with the unround cross-sections, thereby keeping the wire fixed to the rod.

Abstract: A hydraulic actuator includes a pneumatic piston, a hydraulic piston, and an engine valve on a common shaft. The pneumatic piston is urged between first and second stable positions primarily by a double acting pneumatic spring, with high pressure hydraulic fluid connected to a first hydraulic chamber being used to cock the hydraulic piston in a first stable position (engine valve closed). Hydraulic fluid isolated in a second hydraulic chamber is used to latch the hydraulic piston in a second stable position (engine valve open). Transfer of hydraulic fluid between first and second chambers is effected by a carrier for two check valves, which carrier in a first position disables the second check valve to permit fluid to flow from the second chamber to the first chamber, whereupon the first check valve closes (cocking). In a second position the carrier disables the first check valve to permit fluid to flow from the first chamber to the second chamber, whereupon the second check valve closes (latching).

Abstract: Two soft magnetic core halves of amorphous metal are connected together via a non-magnetic gap and the core halves are supported bilaterally by two core supports. The core supports have a connection member at the gap area and at the short-circuit area of the head block thus constructed on both sides of the head gap. The parts of the head are welded by means of the connection members to form a mechanically stable unit.

Abstract: Vapor deposition crucible is provided at least twenty degrees from the central normal to a smooth surface of a screen on which luminescent material is to be deposited. During deposition the surface is rotated relative to the source to produce a layer having a regular structure and a good fill factor.

Abstract: An electrical machine comprises a rotor (2) and a stator (5) as machine parts, means for generating an excitation flux, and active coils (W1-W5). In operation the coils link at least a portion of the excitation flux and generate a rotational e.m.f. The rotor and the stator comprise poles, the number of stator poles (N1-N6, S1-S6) differing from the number of rotor poles (T1.sup.x -T5.sup.x). During operation, the flux pattern of the portion of the excitation flux linking with the active coils rotates relative to the machine part carrying the active coils with such an angular velocity that the absolute value of the difference between said angular velocity and the angular velocity of the machine part comprising the active coils is larger than the absolute value of the difference in angular velocity between the rotor and the stator. For this purpose the pole faces (RS) of the rotor poles, viewed in the circumferential direction of the rotor, have a different width than the pole faces (PS) of the stator poles.

Abstract: An elongated generally cylindrical speed sensing device for sensing the speed of a toothed wheel to one side of the device, the device axis being transverse to the wheel axis and the device being generally tangential to the wheel. An elongated soft magnetic pole piece is surrounded by a coil coaxial with the pole piece, and a laterally extending circular symmetrical pole piece projection extends past an end of the coil to a diameter at least equal to the outside diameter of the coil. An axially magnetized permanent magnet abuts one end of the elongated pole piece. The device housing has rotationally symmetrical mounting surfaces coaxial with the magnetic axis so that angular alignment in installation is not required.