Abstract: A power supply which serves to convert an alternating voltage supplied by an electric mains, into a DC voltage, having a rectifier with input terminals for receiving the alternating voltage and output terminals for supplying a pulsating direct voltage. A first capacitor is connected parallel to the output terminals. An inverter has input terminals connected to the first capacitor. A current limiting circuit is connected between one of the rectifier output terminals and an electrode of the first capacitor in order to limit the inrush current occurring when the power supply is switched on. The current limiting circuit includes a parallel connection of a first resistor and a first switching element, with the first switching element being operative to be in an electrically non-conductive state upon switching on of the power supply and to change over to an electrically conductive state some time after the power supply is switched on.

Abstract: A compact and efficient image projection system is described. The 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: A method for the mutual displacement of at least two parts of an actuator interconnected by a bridge, and such an actuator. The bridge which connects the two parts and extends parallel to a main surface is locally heated through and through with a temperature gradient which is minimized transverse to the main surface, and is subsequently cooled down whereby the length of the bridge between the parts is reduced owing to the plastic deformation which occurs, so that the parts are displaced relative to one another in a direction parallel to the main surface.

Abstract: Vacuum tube comprises a ceramic element and method of interconnecting a ceramic element and a conductive element. A conductive connection consisting of a first layer containing silver and a filler and a second layer containing silver, gold or copper is formed between the ceramic element and the conductive element. The two above-mentioned layers are bonded together by means of diffusion bonding.

Abstract: In a cordless telephony system such as CT1 or CT1.sup.+ there is only a small separation between the transmit and receive frequencies. Consequently, when transceivers with so-called dual frequency synthesizers in a single package are used for the respective receiver and transmitter branches, crosstalk via the synthesizer package occurs between the two branches. To suppress such crosstalk, in accordance with the invention low pass and high pass filters are included in the respective paths from the receiver and transmitter branches through the dual frequency synthesizers.

Abstract: The charge storage elements (3) of an array (2) are arranged in columns and rows and each column is coupled to an associated column conductor (4). Each storage element (3) in a row is coupled to an associated second conductor by a first rectifying element (D1) and to an associated third conductor by a second rectifying element (D2). Each row shares its second and third conductors (5a, 5b, 6a, 6b) with any adjacent rows. One of the two conductors of each row forms a row conductor (5a, 5b) and the other (6a, 6b) one of first and second reference conductors (6a and 6b). Adjacent row conductors (5a, 5b) are separated by a reference conductor (6a or 6b). Each first reference conductor (6a) is separated from any other first reference conductor (6a) by two row conductors (5a, 5b) and a second reference conductor (6b).

Abstract: A magnetic measurement apparatus includes a magnet system (1) for generating a steady magnetic field in a measurement space (35), a gradient coil system (3) for generating gradient fields in the measurement space, and a number of gradient amplifiers (9) with input terminals (38) which are connected to means (7) for generating an input signal exhibiting a predetermined variation as a function of time. The output terminals (39) of at least one of the gradient amplifiers (9) are connected to an output circuit which comprises a series connection of a gradient coil (3) and at least one capacitor (55). The output circuit also includes a transformer (41) with a primary winding (43) and a secondary winding (45), the primary winding being connected to the output terminals (39) of the gradient amplifier (9), the secondary winding constituting a series resonant circuit in conjunction with the gradient coil (3) and the capacitor.

Abstract: A mobile radio set includes a speech processing device for processing digital samples (x(i)) of speech signals which have noise components as well as speech components. Such device includes a control unit for continuously forming estimates of the signal-to-noise ratio of the speech signals by determining and smoothing the power values of the samples thereof, and determining the minimum of each successive group of L smoothed power values. The groups uninterruptedly succeed each other and each contains a sufficient number of smoothed power values so that all the values of a single group associated with a random phoneme of the speech signal can be combined. An estimate of the present signal-to-noise ratio is formed based on the present smoothed power value and the most recently determined minimum successive smoothed power value.

Abstract: In an arrangement of light-sensitive or X-ray sensitive sensors (S.sub.1,1, . . . , S.sub.2048,2048) arranged in a matrix in rows and columns, which sensors produce charge states in dependence upon the amount of incident radiation and each have an electrical switch, for each sensor row a switching line (33.sub.1, . . . , 33.sub.2048) via which the switches (3) can be activated so that the charge states of the sensors of the activated sensor row are read or reset simultaneously via associated read lines (8, 9, 10), there is provided a reset device (30a, 30b) for resetting the charge states of previously read sensor rows, which device activates at least one of the previously read sensor rows, which activates another of the previously read sensor rows after a predetermined number of clock pulses of a reset clock signal (T.sub.32), and which deactivates each activated sensor row a predetermined number of clock pulses after its activation.

Abstract: An FM demodulator having two input terminals (11, 12), to which FM input signals having 90.degree. phase relation are applied, the said FM demodulator including a phase comparator (1) and a tunable, phase shifting circuit (2), the phase shifting circuit (2) being tuned by the FM demodulator output signal via a feedback path comprising a loop, filter. By adding a compensation filter (5) to the tuning control loop the phase shifting circuit is effectively cancelled from the tuning control loop, thereby making the tuning control loop independent of the bandwidth of the phase shifting circuit (2). Thus the bandwidth of the phase shifting circuit (2) can be reduced for threshold extension.

Abstract: Electrically insulating surfaces of an image intensifier are covered with a film of an organic material. This improves the high-voltage behavior of the image intensifier. The image intensifier further has an anode hung by means of insulating rods, which rods are covered by the film.

Abstract: The electrodeless low pressure discharge lamp has a lamp vessel (1) which is fused to the flared portion (6) of a flared tube (5) which extends into the lamp vessel. A power coupler (20) is demountably secured to the lamp vessel and comprises a soft magnetic core (21), surrounded by an electric coil (22), and a heat conducting element (23) in the core. This element is a solid rod, the coil (22) is present in a region (8) adjacent the flared portion (6) of the flared tube (5), and an elastic material couples the rod (23) laterally to the core (21). The construction of the lamp avoids the use of an expensive heat pipe as a heat conducting element.

Abstract: A support element of an automatic load platform of a silicon wafer exposure unit, having a circular cross-section, with a first outer diameter adapted to the guide of a load station, which diameter is smaller than that of a silicon wafer, wherein the circular disc of the support element has at its circumference in a direction parallel to the insertion direction of the load station at least partly enlarged portions and therewith a second outer diameter which corresponds approximately to that of the silicon wafer, and wherein the greatest width of the support element at right angles to the insertion direction corresponds to that of the circular disc.

Abstract: The invention relates to a substrate made from a novel type of ceramic material. This material comprises 44-47 at. % Al, 31-39 at. % O, 8-13 at. % C and 8-12 at. % N. Substrates made from this material exhibit a relatively high heat conductance, a relatively great strength and their coefficient of expansion is equal to that of Si. Consequently, the substrates in accordance with the invention are very suitable for use in the Si-semiconductor technology. The main component of the ceramic material of the substrates preferably corresponds to the formula Al.sub.28 O.sub.21 C.sub.6 N.sub.6. The invention also provides methods of manufacturing substrates and other mouldings from this material.

Abstract: An arrangement for collision prevention is provided for an apparatus, in particular an x-ray examination apparatus, having components that can be moved by drive means. A collision is detected by way of detecting the speed of a relevant moving part and detecting the current and/or power supply to the drive means. Reference values for current and/or power supply at normal operation in dependence of the speed acquired by moving components are provided from a memory means and actually required current and/or power supplies are compared to said reference values. In addition, actual positions of components are detected and compared to computed expected positions of said components. A collision is detected when the required current and/or power supply exceeds a relevant reference value and the detected actual position deviates from the corresponding calculated expected position.

Abstract: A start-up method for a data modem having an echo cancelling loop between the send port and receive port, the loop including a transversal filter having adjustable coefficients, adjustable phase-shifter and a subtractor for subtracting send port data symbols which have been filtered and phase shifted from data symbols received at the receive port. During start-up, in response to a series of data symbols supplied at the send port, a microprocessor iteratively adjusts the filter coefficients and the phase shift to cancel any echo at the output of the subtractor. In order to reduce the convergence time, the start-up method includes estimating the power of the echo over a time period corresponding to a predetermined number of data symbols at the send port, quantizing the estimated power, and adjusting the filter coefficients and the phase shift on the basis of the quantized echo power level.

Abstract: In a digital symbol receiver it is necessary to generate a clock signal with a correct frequency and phase, so that decisions a.sub.k about the value of transmitted symbols a.sub.k can be made at the right detection instants. A simple method of obtaining the desired clock signal is to adjust a VCO by means of a control signal obtained from the correlation of a detection signal r(t) with the detected symbols a.sub.k filtered by a symbol filter. The symbol filter may comprise a cascade connection of a differentiator and a filter which has a transfer function which is an estimate of the transfer function of a channel which supplies the transmitted symbols.

Abstract: A circuit for recognizing a human face in a sequence of video is provided. The circuit includes a block structuring circuit in which the video is structured block-wise and wherein two consecutive frames are subtracted from one another. The circuit also includes a unit for block-wise post-processing the difference frames. The post-processing unit includes a comparator for determining the areas of the difference picture which may correspond to a moving object, a mapping unit for forming a status picture by mapping each block of the difference picture which corresponds to a moving object onto a binary "one", all other blocks being mapped to a binary "zero".The status picture is transformed by a transforming unit into a unidimensional feature function. The unidimensional feature function is then fed to a convolution unit to determine whether the feature function could include a "head-shoulder" scene.

Abstract: The storage elements (3) of an array (2) are arranged in rows and columns with the storage elements (3) in a column being coupled to a first conductor (4) and the storage elements (3) in a row being coupled to a second (5) and to a third (6) conductor. Each storage element (3) in a row is coupled to the associated second conductor (5) by a first rectifying element (D1) and to the associated third conductor (6) by a second rectifying element (D2) with the first and second rectifying elements (D1 and D2) allowing the passage of current when forward-biased by applied voltages. The third conductors (6) also form the second conductors (5) of any adjacent rows. The first and second rectifying elements (D1' and D2') of alternate rows (N, N+2, N+4, . . . ) are oppositely oriented to those (D1" and D2") in the remaining rows (N+1, N+3, . . . ).

Abstract: A semiconductor device includes a semiconductor body (1) having a semiconductor element with connection points (2, 3) which adjoins a surface (4) of the semiconductor body (1) and is laterally insulated and surrounded by a first depression (5) in the surface (4), which depression (5) is provided with a wall (6) and a bottom (7), while the surface (4) of the semiconductor body (1) and the wall (6) and bottom (7) of the depression (5) are covered with an insulating layer (8). The connection points (2, 3) are provided in the insulating layer (8) on the surface (4) of the semiconductor body (1) and are connected to conductor tracks (10, 11) which connect the connection points (2, 3) across a wall (6) to connection surfaces (12, 13) associated with the connection points (2, 3) and situated on the bottom (7). It is found in practice that, in the case of progressive miniaturization, the manufacture of such devices leads to rejects caused by short-circuits between connection surfaces (12, 13).