Abstract: A low profile magnetic component such as an inductor or transformer includes a core and a planar magnetic winding body having a dense, rigid structure composed of a stack of individual winding patterns separated by insulating layers, and a binder/filler material. The input and output termini of the individual winding patterns are revealed in a side face of the winding body, where they are interconnected with a plated metallization. Such structures may be mounted onto a PC board, and are useful, for example, in electronic ballasts for the lighting industry.

Abstract: Playback apparatus for a record carrier on which information is recorded in the form of variations of a first physical parameter. The playback apparatus scans the record carrier by means of a transducer which is responsive to the variations of the first physical parameter. An information recovery circuit recovers the information from a detection signal produced by the transducer. The record carrier also exhibits a variation of a second physical parameter, which differs from the first physical parameter but is of a type which is detectable by the same transducer. A detection circuit detects the presence of the second variation on the basis of a further detection signal produced by the transducer. A circuit controlled by the detection circuit enables the information recovery circuit in the event that the presence of the second variations is detected.

Abstract: A TV signal receiver has a tuner for deriving a first TV signal from the input signal, and a device for storing in a memory and reading therefrom a plurality of blocks of a second TV signal derived from the input signal. The first TV signal has interruptions during which a block of the second TV signal is insertable so as to obtain a composite TV signal which is supplied at an output terminal of the receiver.

Abstract: The invention relates to a radiation-sensitive device comprising a thin radiation-sensitive element (2), in particular a thin photodiode (2). The device includes a substrate (1) on which a photodiode (2) is provided. The surface (5) of the photodiode serves as a semi-pervious mirror (5) through which the radiation (100) enters; a reflecting layer (6) situated between the photodiode (2) and the substrate (1) also serves as a mirror (6). As a result, a so-called resonant cavity effect is possible, resulting, inter alia, in wavelength selectivity of the device. The known device has insufficient wavelength selectivity, which, in addition, cannot readily be set in an accurate and reproducible manner. A device in accordance with the invention is characterized in that the reflecting layer (6) is a metal layer (6) and in that the photodiode (2) is secured to the substrate (1) by means of an adhesive layer (7).

Abstract: A disc-shaped information carrier has a track thereon which follows a helical or concentric path forming successive windings. For identifying each winding the information carrier also has a servo pattern thereon which includes position-information as well as synchronization elements. Such elements may be, for example, brief pulses in a continuous track wobble, and are distinguishable in adjacent windings based on a predetermined detectable parameter, such as alternating polarity or shifted relative phase positions. During recording by a read/write head a system control detects the synchronization elements and monitors whether a deviation has occurred signifying that the read/write head has wandered to an adjacent winding. In that event recording is interrupted. Thus, the least possible information in adjacent windings is overwritten in the case of disturbances resulting from shocks or defects of the information carrier.

Abstract: Bus driver having a P-channel output transistor (T1) for driving a first bus terminal (6) from a positive supply terminal (2), an N-channel output transistor (T2) for driving a second bus terminal (12) from a negative supply terminal (4), a P-channel driver transistor (T3) and an N-channel driver transistor (T4) series connected between the positive (2) and the negative (4) supply terminal. The control electrodes of the P-channel transistors (T1, T3) are interconnected and the control electrodes of the N-channel transistors (T2, T4) are interconnected to obtain a fixed relationship between the currents through the P-channel transistors (T1, T3) and through the N-channel transistors (T2, T4). The conduction of the driver transistors (T3, T4) is controlled by two floating control voltage sources (22, 24) which are connected between the interconnection node (20) of the driver transistors (T3, T4) and the respective control electrodes of the driver transistors.

Abstract: A scanning device for an optical record carrier (1) comprises a high-numerical aperture dual lens objective system (10, 11) for focussing a radiation beam (7) on an information layer (3) of the record carrier. The lens (11) of the objective system closest to the record carrier is tilted by a tilt servo system in response to tilt of the record carrier. The tilt angle of the lens is preferably less than the tilt angle of the record carrier in order to reduce optical aberrations of the radiation beam such as coma and astigmatism.

Abstract: In an electronic system for the transmission of data between a plurality of stations the control signals and functions of the basic elements of power supply, watchdog and signal converter in each station are linked to one another so as to ensure that the number of possible modes of operation, taken for all the elements, is reduced to a number necessary for the corresponding task and thereby guarantees a more reliable operation. Moreover, the linkage leads to an optimum default behavior of the station with regard to application-specific power-saving and safety requirements, even when, for example, the malfunction of the microcontroller of the station persists.

Abstract: Short-circuits are liable to occur between the two conductors in a system in which data and/or energy is transmitted to a plurality of receivers/users via two conductors. Transmission is then interrupted and the supply source is inadmissibly over-loaded. The invention provides disconnecting units which recognize occurrence of short-circuits between the conductors and, in response thereto, isolate the part of the system in which the short-circuit has occurred from the supply of data and/or energy, so that the remainder of the system remains operational. After removal of the short-circuit, the isolated part is automatically re-connected to the system. The potential on the conductors ahead of and following a disconnecting unit is monitored via current limiting circuit elements which bridge a switch in the disconnecting unit.

Abstract: In the standard format now adapted by FCC for a digital HDTV signal, the video data symbols are interleaved and trellis encoded in accordance with a 4-state trellis code and the interleaving is of sequences of every 12 successive symbols. At the receiver the trellis decoder is therefore projected to consist of 12 respective decoder stages for the 12 interleaved sequences, each decoder stage having a branch metric calculator unit (BMC), an add-compare-select (ACS) unit and a path memory unit (PMU). The present invention separates the path memory requirements for the 12 interleaved sequences from the requisite BMC and ACS functions, so that the latter two units can provide those functions for all of the 12 interleaved sequences. A single extended PMU provides for storage of pointers to possible predecessor states of the trellis code corresponding to a present state thereof, going back to a predetermined number (such as 16) of sequentially preceding received symbol values.

Abstract: In a speech encoder (4), a speech signal is encoded using a voiced speech encoder (16) and an unvoiced speech encoder (14). Both speech encoders (14,16) use analysis coefficients to represent the speech signal. The analysis coefficients are determined more frequently when a transition from voiced to unvoiced speech or vice versa is detected. This has been found to achieve significantly improved quality of speech reproduced from the encoded speech signal.

Abstract: A magneto-optical storage medium for the repeated writing of information at a write temperature T.sub.w, or at two write temperatures T.sub.h, T.sub.i, above the room temperature T.sub.a and for the repeated reading out at a temperature T.sub.m, with a front mask at the temperature T.sub.f and a rear mask at a temperature T.sub.r, above the room temperature T.sub.a, in an external magnetic field H.sub.e, which medium includes a substrate, a first magnetic layer which is disposed on the substrate and has a temperature-dependent coercivity H.sub.C1 (T), a compensation temperature T.sub.cp1 and a Curie temperature T.sub.C1, a second magnetic layer which is disposed on the first magnetic layer and has a temperature-dependent coercivity H.sub.C2 (T), a compensation temperature T.sub.cp2 and a Curie temperature T.sub.C2, and a third magnetic layer which is disposed on the second magnetic layer and has a temperature-dependent coercivity H.sub.C3 (T), a compensation temperature T.sub.cp3 and a Curie temperature T.

Abstract: A method and apparatus for forming a visual index of scenes in a video image which has been or is being recorded in a computer readable memory. A selected number of keyframes are derived from the recorded image, each being representative of a respective scene therein. The keyframes are then ordered into a selected number of levels of detail of the scenes represented thereby, each level including a predetermined number of keyframes, each subsequent level including keyframes of greater detail than those in a preceding level. A header file is then formed which is descriptive of the ordered set of keyframes, and the header file is stored together with the ordered set of keyframes in the computer readable memory. A user can thereby identify and obtain optimized retrieval in accordance with his preferences of particular segments of the video image from a relatively slow memory device.

Abstract: In a motion-dependent noise filtering (MD, NRF), a received image signal and a delayed (3) image signal are combined in dependence upon both a local amount of motion and a global amount of motion in the image signals.

Abstract: Picture information intended for being displayed on a picture screen contains not only the main information such as film pictures, but also overlay information such as graphic information or subtitles. The overlay information is transmitted separately from the main information and is encoded in packets of digital symbols in which a page of overlay information is represented by a group of packets. All the packets include identification information sufficient for a receiver to identify whether all packets of a group have. This makes it possible to ascertain whether a page of overlay information has been received completely, which allows incomplete pages or combinations of parts of pages from being displayed on the picture screen. This is advantageous in the case of interruptions of picture signal reception, such as a disturbed TV signal, or when a video disc or tape is used in trick modes such as Fast Forward.

Abstract: A radiation measurement system includes a dipole antenna (4,18) for radiating an EM field in response to an electrical signal generated by an opto-electrical converter (12). The opto-electrical converter (12) is provided with an optical signal representing the EM field to be emitted. Optical signals avoid disturbance of the EM field by a coaxial cable required to feed the antenna. In order to obtain an ideal dipole antenna with well known radiation properties, an inner conductor (16) is used to couple the signal from the opto-electrical converter (12) to both halves (4,18) of a hollow dipole antenna. FIG.

Abstract: A device for mounting a head support (12), which carries a magnetic head (13) at its front, on a head disc (15). The head support (12) is mounted in a separate housing (10) and the housing (10) is secured to the head disc (15) in order to improve the reliability.

Abstract: Apparatus for optically scanning an information plane of a disc-shaped optical record carrier having an underlying surface extending parallel to the information plane. A radiation source supplies a scanning beam, and an optical scanning unit has a lens system which focuses the scanning beam to a scanning spot on the information plane. The lens system has an optical axis, a first lens unit with a first lens having an entrance side (11) and an exit side (13), and a second lens unit with a second lens situated opposite the exit side of the first lens. The scanning unit also includes a drive motor for displacing the first lens along the optical axis and a rotation element for adjusting the position of the second lens with respect to the underlying surface of the record carrier. To inhibit spherical and/or comatic and astigmatism aberrations during scanning, the rotation element is rotatably driven and forms part of the second lens unit.

Abstract: A system for controlling the playing of rented compact discs on an end-user's compact disc player. The end-user obtains a validation disc on which is stored a control program and an expiry date. When the validation disc is inserted into the user's player, the player downloads the control program into its memory and runs the program. This causes the expiry date to be read from the disc and stored in the player's memory. Discs to be played on the player have stored thereon a second control program which is downloaded into the player's memory when they are inserted into the player. This second control program causes the player to check whether or not the current date, as maintained by the player, is later than the stored expiry date. If the current date is later, playing of the disc is prevented, whilst if it is earlier, playing of the disc is allowed.

Abstract: An electronic ballast for an electron discharge lamp includes a resonant inverter driven by a high frequency switching signal supplied by a drive circuit which is substantially comprised in an integrated circuit, the lamp being connected in an output circuit of the inverter and powered thereby. The lamp intensity is controlled by changing the switching signal frequency, thereby changing the power supplied to the lamp. In order to prevent parasitic capacitance of remote wiring between the ballast and the lamp from causing inaccuracies in determination of the power being supplied to the lamp, the ballast takes into account the phase difference between lamp current and voltage in making such determination. For example, by deriving the product of rectified lamp voltage and rectified lamp current, and using the arithmetic summation of such products during each operating cycle as a measure of lamp power.