Abstract: An emitter follower amplifier is coupled between the output of a high voltage video amplifier and the cathode of a kinescope for reducing the effective capacitance presented to the video amplifier that is attributable to the kinescope cathode, socket, spark gaps, and related stray capacitances. A secondary undesired capacitance loading of the video amplifier is effectively reduced by regulating the collector-emitter voltages of the emitter follower output transistors at substantially constant values thereby improving parameters such as slew rate and bandwidth of the overall video display system. Nonlinear circuitry in the follower circuit facilitates accurate AKB current sensing and provides simplification of the voltage regulation circuitry. White limiting circuitry is included within the video amplifier for reducing excess peak white drive that results in objectionable smears.

Abstract: An input filter stage and to a method for filtering a data stream.

Abstract: The present invention relates to a device for the reading and/or writing of optical recording media [(AT)] of various structures, which device operates with a single objective lens [(OL)]. The invention proposes to use a diaphragm varying in diameter, in particular a polarizing filter arranged in the optical path in order to adapt the aperture to each type of optical recording medium [(AT)] used. The wavefront can be corrected using a divergent lens [(SL)] which can also be positioned in the beam path. The Diaphragm formed by the polarizing filter PF is linked to the objective lens [(OL)]. The field of application of the invention relates to, in particular, devices for reading and/or writing optical recording media [(AT)] of various structure such as compact discs and digital video discs.

Abstract: Disturbance detection is used to detect anomalies in the behaviour of the data signal. The data signal may for example be a readout signal in an optical drive. An upper and a lower envelope signal value for the data signal are determined in a determined time interval (&Dgr;(m−1)). During the following time interval (&Dgr;(m)) a difference value is computed by subtracting from each other the values of the lower from the upper envelope signals. A disturbance is detected in case the difference value is smaller than a predetermined border value.

Abstract: A method and apparatus for processing information stored on a storage medium, such as a digital video disk, involves accessing information stored on the medium and determining whether information stored on the storage medium includes unrated program information. If so, a user is given the opportunity to override a control condition of the system that prevents playback of unrated program information. If override is selected, playback of the unrated program information is enabled and, upon completion of playback, the control condition of the system may be restored to prevent playback of other unrated program information. Override may be conditioned upon the user first entering a password. The mode of operation that permits override of the control condition for preventing playback of unrated program information mode of operation may be selectively enabled.

Abstract: The process for the compression of digital data from a video image which carries out a partitioning (4) of the image into image blocks, a Discrete Cosine Transformation (9) of these blocks so as to deliver coefficients and a quantization (10) of each coefficient using a quantization interval, is characterized in that it also carries out a segmentation (2) of the image and a labelling (2) of the regions obtained, and in that it associates with each block a block control interval on the basis of which the quantization interval for each coefficient of the block is defined, the value of which is calculated as a function of these labels.

Abstract: A device for rotating inside of a disk player and/or recorder a disk shaped data carrier which takes into account that the rotating disk may be eccentered from an imposed rotation axis. Side moving means allow the rotating disk and the fixing means to which the disk is removably fixed, to move inside said player and/or recorder in a rotation plane substantially perpendicular to an axis of rotation of said fixing means. The rotating disk and the fixing means go into a gyroscopic movement inside the player. A plurality of examples to realize the invention are described.

Abstract: A photodiode detection circuit is used to automatically identify a type of photodiode circuit connected to it. The photodiode circuit comprises at least a photodiode. Once the type of photodiode circuit has been identified by applying a current to it and evaluating a voltage occuring at an input of the detection circuit the photodetection circuit adapts itself to it, e.g. a reverse biasing voltage is/isn't applied to the photodiode of the photodiode circuit. The result is a photodiode detection circuit which uses a forward or a reversed biased photodiode. The photodiode detection circuit is now in a state to measure light falling on the photodiode. The detection circuit may be part of a light intensity monitoring and controlling circuit which allows to regulate the intensity of a laser beam in an optical disk reading/recording device.

Abstract: An apparatus and concomitant method for generating an OSD message by constructing an OSD bitstream having OSD data defining a plurality of alternate OSD pixel lines. The OSD bitstream contains an OSD header and OSD data. An OSD unit retrieves pixel control information from the OSD header which is programmed by a processor of a decoding/displaying system. The OSD header contains information that is used to program a color palette of the OSD unit and to provide instructions as to the treatment of the OSD data. If the “Line Doubling Mode” is enabled in the OSD header, then the OSD unit will repeat each OSD line on the next line of video for an OSD region.

Abstract: A signal distribution apparatus having a learning feature for recognizing a remote control device code associated with a particular signal source and coupling the associated signal source to an output in response to receipt of the device code. The remote control device code may be transmitted using a universal remote control device or a dedicated remote control device associated with the particular signal source. The present invention allows a user to couple a plurality of signal sources and a display device, such as a television set, to the present signal distribution apparatus and thereafter couple a selected one of the signal sources to the display device using the universal remote control device or the dedicated remote control device. The learning feature obviates the need for a dedicated remote control for the signal distribution device.

Abstract: At the onset of ageing or in the further course of their service life, color picture tubes relatively frequently exhibit a rise in the field strength between the cathode (K) and the Wehnelt electrode (G1) of the respective beam system on account of a blooming effect of the cathodes (K) which is known per se and reduces the spacing between cathode (K) and Wehnelt electrode (G1). The cut-off regulation reacts to an effect of this type in a manner such that the reverse voltage acting between cathode (K) and Wehnelt electrode (G1) is correspondingly reduced in order to be able to drive the same reference cathode current. However, the reaction of the cut-off regulation must be taken into account for the circuit design since this would otherwise result in an unacceptable reduction in the modulation range, which would, in turn, have an adverse effect on the maximum contrast setting.

Abstract: A method and apparatus for dynamic contrast improvement in video pictures. There is a strong demand for picture contrast but each video display has a limited dynamic range. The picture contrast can't be increased by simply increasing the video signal amplitude because exceeding the display dynamic range in some video scenes causes unwanted disturbing effects. According to the present invention the video pictures are analysed framewise in real time and the parameters of a transfer function for contrast improvement are adjusted depending on the analysis results for the best subjective picture quality.

Abstract: A grid kick circuit for applying beam cut-off bias to the grid of a kinescope to provide spot burn protection. The circuit includes a first switching circuit having an output coupled to a first electrode of a grid kick capacitor and a second switching circuit having an output coupled to a second electrode of the capacitor and the grid. When beam blanking is not desired, charging current is supplied to the capacitor through a first current path from a first voltage source while the second switching circuit regulates the voltage at a second electrode of the capacitor and the grid. Current for the second switching circuit is provided by a second current path which is coupled to the first voltage source and is independent of the first path.

Abstract: Display apparatus includes a kinescope cathode current sensor (18) coupled to a load (200) for developing a beam current measurement pulse during a beam current measurement interval. Overshoots in the pulses are suppressed by a pulse correction circuit (300) comprising a first capacitor (Ca) coupled from the load circuit (200) to a source of reference potential (Gr) via a switch (Q300); and a control circuit (Ca, Ra, Rb), responsive to the presence of the overshoot, for closing the switch for a predetermined length of time and for opening the switch otherwise.

Abstract: A device for writing to and/or reading from optical recording media having different structures is described, for example, a device which is suitable both for writing to/reading from digital videodisks (DVD) and conventional CD's. Provision is made for measuring the intensity of each peak in the mirror signal while the objective lens is moving to the recording medium. The intensity e.g. at the instant of the positive-negative crossing of the focus error signal is taken in this case. The type of optical recording medium is determined from the time characteristic and/or the height distribution of the peaks. In order to identify the type of optical recording medium, different properties of the optical recording medium are taken into account, such as reflectivity of the corresponding reflective surface, reduced intensity modulation due to spherical aberration, time characteristic and the like.

Abstract: The present invention relates to a device for reading from and/or writing to optical recording media, which has a tracking unit, a four-quadrant detector, two summation points and a phase comparator for tracking in accordance with the differential phase detection method, and also two variable delay elements which can be set by a control unit. The device has improved compensation of the error in the track error signal and thus in the tracking signal. The error is caused by lens movement. An interference signal generating unit whose output is connected to the tracking unit and to a first input of the control unit, the second input of which is connected to the output of the phase comparator for providing error compensation.

Abstract: The invention concerns an apparatus for reading or writing optical recording carriers, the apparatus using the differential phase detection process for tracking purposes. This process exhibits shortcomings when optical recording carriers of different pit depths are to be used. The object of the invention is to design an apparatus of this type which can also be used with said optical recording carriers. This object is achieved in that delay members are disposed between the photodetector and phase detector. The apparatus according to the invention is used as a playback or recording apparatus for optical recording carriers, such as CDs, CD-ROMs, CD-Is, CD-Rs, DVDs, DVD-ROMs, DVD-Rs, etc.

Abstract: A stand alone CD player for reading data from a recording medium having data formatted in accordance with CD-like recording formats, for example, CD-ROM, CD-I and CD-V, stored thereon. According to the present invention, the playback of data from a recording medium having data in such a recording format is made possible by a virtual table of contents generated by the stand alone CD player. The virtual table of contents also enables sequential access to data stored on the recording medium that has a table of contents that cannot be read by the present CD player.

Abstract: A power transmission system with a gearwheel and a toothed rack, having an engagement securing system that ensures increased power transmission and protection of the toothing in the end region of the rack. According to the invention the engagement securing system comprises a lug disposed on the rack, which lug engages a guide connected to the gearwheel. In the exemplary embodiment the guide comprises a groove disposed on a disk coupled to the gearwheel. Advantageously, no additional individual parts are required. The range of applications includes an automatic transport securing system in recording or playback equipment for optical, magneto-optical or other recording media, as well as other rack drive systems that require increased power transmission in the end region of the rack.

Abstract: The present invention relates to a recording or replay device, and to a method for recognizing a focussing status. The object of the invention is to provide a method of this type and a recording or replay device, with the facility of producing significant astigmatism in the reflected light beam (15) simply and cost-efficiently without elaborate alignment. This object is achieved by the use of a birefringent element (23, 24). The invention is, in particular, suitable for use in a recording or replay device for writing to or playing back optical recording media (11) such as CDs, video discs, DVDs and the like.