Abstract: A method for determining a position of a phase centre of an antenna arranged in a mobile device, in particular a vehicle, wherein the antenna is operable to receive satellite signals in a global navigation satellite system, the method comprising: receiving, with the antenna, satellite signals from satellites of the global navigation satellite system; determining a direction from which the satellite signals are received based on the received satellite signals; and determining the position of the phase centre of the antenna based on the direction from which the satellite signals are received and stored correlation information indicative of a correlation between the position of the phase centre and the direction from which the satellite signals are received.

Abstract: A method for determining a position of a phase centre of an antenna arranged in a mobile device, in particular a vehicle, wherein the antenna is operable to receive satellite signals in a global navigation satellite system, the method comprising: receiving, with the antenna, satellite signals from satellites of the global navigation satellite system; determining a direction from which the satellite signals are received based on the received satellite signals; and determining the position of the phase centre of the antenna based on the direction from which the satellite signals are received and stored correlation information indicative of a correlation between the position of the phase centre and the direction from which the satellite signals are received.

Abstract: The invention relates to a method for transmitting a write strategy to a laser driver, and to a pickup and an apparatus for writing to or reading from and writing to optical recording media using such method. According to the invention, the method has the steps of: transmitting an encrypted write strategy to the laser driver; and decrypting the transmitted write strategy with a decryption key stored in a first memory of the laser driver.

Abstract: In order to obtain a corrected or compensated focus error signal or track error signal, it is proposed to generate primary and secondary scanning beams incident on adjacent tracks of an optical recording medium and to detect the primary and secondary scanning beams reflected from the optical recording medium in order to derive from them primary-beam and secondary-beam focus error signals or primary-beam and secondary-beam track error signals, which are subsequently normalized in order to obtain the compensated focus error signal or track error signal from the normalized primary-beam and secondary-beam error signals by means of weighted combinations. As a result of the normalization, the corrected or compensated focus error signal or track error signal is generated independently of the reflection properties of the respectively scanned track.

Abstract: The invention relates to a serial data transfer in a numerically controlled control system to update an output value of the control system. A variable write depth shift register is used to update an output value of the control system in such a way that only a number of bits of a data word, which has to be updated to form the updated output value via a serial data transfer is transferred to the variable write depth shift register, so that the output value is updated in a shorter time and can be updated more frequently. The variable write depth shift register is applicable in a numerically controlled control system in which long data words and shift register are used to update the output value via serial data transfer.

Abstract: A magneto-optical recording or reproducing device having an information erasing means for erasing information or data recorded on a magneto-optical recording medium. According to the invention, the information erasing means comprises an erasing magnet having a field strength sufficient to initialize the magneto-optical recording medium without the assistance of a laser and/or an optical scanning device.

Abstract: The invention relates to a serial data transfer in a numerically controlled control system to update an output value of the control system. A variable write depth shift register is used to update an output value of the control system in such a way that only a number of bits of a data word, which has to be updated to form the updated output value via a serial data transfer is transferred to the variable write depth shift register, so that the output value is updated in a shorter time and can be updated more frequently. The variable write depth shift register is applicable in a numerically controlled control system in which long data words and shift register are used to update the output value via serial data transfer.

Abstract: The invention relates to a compatible optical scanner with an improved laser modulator for recording or reproduction apparatuses of optical recording media. Although the input characteristic curves of older and newer optical scanners fundamentally differ on account of different modulator circuits, a circuit arrangement for an optical scanner with an improved laser modulator is specified which is completely compatible with previously used optical scanners. The compatible scanner with an improved laser modulator, which is a laser modulator that at least partly or completely switches the laser current, has, at its input, a means for simulating the input characteristic curve of a laser, which means is formed for example by series?connected diodes D1 . . . Dn or a zener diode that interacts with a current mirror at the input of the optical scanner.

Abstract: The invention relates to a method for transmitting a write strategy to a laser driver, and to a pickup and an apparatus for writing to or reading from and writing to optical recording media using such method. According to the invention, the method has the steps of: transmitting an encrypted write strategy to the laser driver; and decrypting the transmitted write strategy with a decryption key stored in a first memory of the laser driver.

Abstract: The invention relates to an intrinsically safe pick-up for reproduction or recording devices for different optical recording media, which have at least two lasers with a monitor diode which is used jointly for the lasers, such as a monitor diode which is integrated in a twin laser. The intrinsically safe pick-up has a switching means, which is formed by interlocked switches, by means of which both a reference value, which is associated with one laser diode with the monitor diode, is produced in order to control the light power of the laser diode, while at the same time preventing simultaneous actuation of the laser diodes or incorrect association of a light power adjusting means leading to overloading or to destruction of the twin laser. A reproduction or recording device which is designed with an intrinsically safe pick-up for different optical recording media does not require any additional changeover switches, which would otherwise need to be provided between a DVD/CD circuit and the pick-up.

Abstract: The present invention relates to a device for reading from and/or writing to optical recording media having a scanning unit, which is equipped with at least two detector units each having a plurality of detector elements, and also an evaluation unit, each of the detector elements being connected to the evaluation unit by means of a line. The object of the present invention is to simplify the structure of a device of this type. This object is achieved by virtue of the fact that detector elements of different detector units are each connected to the evaluation unit via a single line. The device according to the invention is advantageously a device which can read from and/or write to not only optical recording media which correspond to a CD standard but also those which correspond to a DVD standard.

Abstract: In order to obtain a corrected or compensated focus error signal or track error signal, it is proposed to generate primary and secondary scanning beams incident on adjacent tracks of an optical recording medium and to detect the primary and secondary scanning beams reflected from the optical recording medium in order to derive from them primary-beam and secondary-beam focus error signals or primary-beam and secondary-beam track error signals, which are subsequently normalized in order to obtain the compensated focus error signal or track error signal from the normalized primary-beam and secondary-beam error signals by means of weighted combinations. As a result of the normalization, the corrected or compensated focus error signal or track error signal is generated independently of the reflection properties of the respectively scanned track.

Abstract: A method of accelerating the identification of the type of data carrier when the data carrier is inserted in a multimode player and/or recorder which accepts different types of data carriers Looking up a table of use statistics allows the present method to determine which data carrier type is most often used, thus most probable to be encountered, and to select a parameter or a set of parameters associated with this type to test the data carrier.

Abstract: A device for reading from and/or writing to optical recording media, the device comprising a light source for producing a scanning beam, a photodetector for detecting the scanning beam reflected by the recording medium and a semi-transparent mirror arranged in the beam path for directing the scanning beam onto the recording medium and the reflected scanning beam onto the photodetector. An object of the invention is to improve a device of this type, in particular with regard to reducing the production costs. This object is achieved by the semi-transparent mirror being a plane-parallel plate with a layered structure, and a partially reflective layer being arranged between two small carrier plates.

Abstract: The present invention relates to a device for reading from and/or writing to optical recording media having a scanning unit, which is equipped with at least two detector units each having a plurality of detector elements, and also an evaluation unit, each of the detector elements being connected to the evaluation unit by means of a line.

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 (6), which has a light source (1) for producing a scanning beam (2), a photodetector (7) for detecting the scanning beam (2) reflected by the recording medium (6) and a semi-transparent mirror (3) arranged in the beam path for directing the scanning beam (2) onto the recording medium (6) and the reflected scanning beam (2) onto the photodetector (7).

Abstract: The invention relates to a method and an arrangement for a compatible recording and/or reproduction device for the reproduction of information from, and/or for recording on, optical information carriers (CD) having differing information storage densities. A light source is used which is adapted to the highest storage density of the information carriers (CD) to be used as regards wavelength and light spot dimensions and the light directed onto the information carrier (CD) is defocused by a defocusing means for the enlargement of the light spot for information carriers (CD) of lower storage density.

Abstract: Method for the correction of a tracking error signal during optical scanning of a recording medium in the form of a disc. In the case of MO discs, the Kerr rotation angle is in general very small, so that so-called enhancement is used for processing. This leads to birefringence effects which are thermally induced on the WO disc during the writing process producing a noise level on the track error signal. According to the invention, an optical scanner arrangement is used to determine light intensities from two mutually perpendicular polarization planes. A noise element, which is produced by interfering polarization rotation of the light, in the tracking error signal is compensated by linking the electrical output signals of the scanner arrangement. Applicable both to MO and WO as well as CD audio, CD video and CD-ROM.

Abstract: The invention concerns a high storage capacity ROM-RAM disk and a process for reading and writing to the ROM-RAM disk. T he aim of the invention is to devise a ROM-RAM disk and a process making it possible to read ROM and RAM simultaneously, to read the ROM area and at the same time write to the RAM area and to provide the largest possible volume of memory. The invention comprises two alternative designs. In a first design a ROM-RAM disk contains an area having both ROM and RAM memory structures as of a certain radius or diameter, establishing therein, at a constant rotational speed, a scanning/writing speed which ensures a reading/separation of the data stored in the ROM-RAM structures. In a second design, the available storage area is taken up entirely by a ROM-RAM storage area, where RAM memory structures have a reduced data rate in order to form, a length of memory structures necessary for separating the data stored in the ROM-RAM storage area.