Abstract: A lead screw actuator for displacing holder with a collimator lens in an optical scanning device has a home-position for accurately determining the position of the collimator lens. An anti-seize construction is provided to avoid the holder to get stuck against the home-position due to the friction between both surfaces.

Abstract: A lead screw actuator for displacing holder with a collimator lens in an optical scanning device has a home-position for accurately determining the position of the collimator lens. An anti-seize construction is provided to avoid the holder to get stuck against the home-position due to the friction between both surfaces.

Abstract: Information carrier comprising a disc (1) provided with positioning means (3) arranged to cooperate with a disc drive turntable (4) for positioning the disc on the turntable. The positioning means are movable at least in a transversal disc direction (T) relative to the disc.

Abstract: The invention relates to a pickup unit (1) for reading and/or writing data on a disk (2). The pickup unit (1) comprises a lens (5) in a lens holder (6) which is connected to a frame (7) of the pickup unit (1) by a plurality of elastic support members (8). The lens holder (6) is movable with respect to the disk (2) by bending of the elastic support members (8). The mounting position (9) of each elastic support member (8) at the lens holder (6) is located closer to the disk (2) than the respective mounting position (10) of the elastic support member (8) at the frame (7), as seen in the focusing direction of the lens (5). In this manner the lens holder (6) with the lens (5) is adapted to be brought to an operating distance with respect to the disk (2) which is smaller than the flatness tolerances of the disk (2) without the risk of collisions between the frame (7) and the rotating disk (2).

Abstract: A scanning device for a disc-shaped information carrier about an axis of rotation having a linear motor that can displace the scanning unit in a radial direction. The linear motor comprises a first part and a second part guided with respect to each other in the radial direction by a straight guide. The first part comprises pairs of magnets having opposite directions of magnetization. The second part includes an electric coil system with winding portions. The linear motor is further provided with a control unit for controlling an electric current in the coil system. The control unit controls electric current in the winding portions if the winding portion is present in a magnetic transition region between the pair of magnets, resulting in a Lorentz force in the winding portion, substantially perpendicularly to the straight guide. The Lorentz force is used to fix the degrees of freedom of the second part with respect to the first part.

Abstract: A method and an apparatus for reading and/or writing data on a disk (1) storing data in a continuous spiral form (2). The data is simultaneously read from or written to N tracks (4-8, 12-20) by N spots, N being an integer larger than or equal to 2. The reading and/or writing is performed by alternating between reading/writing and actuator jumps. In order to increase the efficiency of such multi track disk drives a next jump decision is calculated dynamically on the basis of a real-time analysis determining a next position of a unit (23) for reading/writing data relative to the disk (1).

Abstract: The invention relates to a method and an apparatus for reading and/or writing data on a disk (1) storing data in a continuous spiral form (2). The data is simultaneously read from or written to N tracks (4-8, 12-20) by N spots, N being an integer larger than or equal to 2. The reading and/or writing is performed by alternating between reading/writing and actuator jumps. In order to increase the efficiency of such multi track disk drives a next jump decision is calculated dynamically on the basis of a real-time analysis determining a next position of a unit (23) for reading/writing data relative to the disk (1).

Abstract: The invention relates to a scanning device (1) for scanning a disc-shaped information carrier (11), such as a CD or DVD. The scanning device comprises a table (3) for the information carrier, which is rotatable about an axis of rotation (7). The scanning device further comprises a scanning unit (13) and a linear motor (29) by means of which the scanning unit can be displaced with respect to the table in a radial direction (X, X′). Said linear motor comprises a first part (39) and a second part (41) which are guided with respect to each other in said radial direction by means of a straight guide (27). Said first part comprises pairs of magnets (47, 49) having opposite directions of magnetization (M, M′) which extend substantially perpendicularly to the straight guide. Said second part comprises an electric coil system (51) having winding portions (65, 67) extending substantially perpendicularly to said directions of magnetization and to said straight guide.