Abstract: An actuator or sensor device comprises an electroactive polymer (EAP) arrangement which extends between fixed opposite ends. The electroactive polymer arrangement comprises a passive carrier layer and an active electroactive polymer layer, wherein at or adjacent the ends, the passive carrier layer and the active EAP layer are mounted with one over the other in a first order, and at a middle area between the ends, the carrier layer and the active EAP layer are mounted in an opposite order. This enables internal stresses and moments within the electroactive polymer arrangement to be used more effectively to contribute to displacement or actuation force.

Abstract: An actuator or sensor device comprises an electroactive polymer (EAP) arrangement which extends between fixed opposite ends. The electroactive polymer arrangement comprises a passive carrier layer and an active electroactive polymer layer, wherein at or adjacent the ends, the passive carrier layer and the active EAP layer are mounted with one over the other in a first order, and at a middle area between the ends, the carrier layer and the active EAP layer are mounted in an opposite order. This enables internal stresses and moments within the electroactive polymer arrangement to be used more effectively to contribute to displacement or actuation force.

Abstract: The invention relates to an optical scanning device for scanning in a first mode a first information layer (111) of an information carrier and in a second mode a second information layer (112) of the information carrier. The optical scanning device comprises a radiation source (101) for generating a radiation beam (102), an objective system (105) for focusing an entrance beam on an information layer and an optical element (103) arranged between the radiation source and the objective system, for converting said radiation beam into a diverging entrance beam in the first mode and a converging entrance beam in the second mode.

Abstract: An optical data reading/writing device for reading/writing to an information layer, the device comprising at least a first radiation source (12) for generating a radiation beam and an optical system (10, 40, 44, 46, 48, 50, 52, 54, 56) for converging the radiation beam on the information layer and for converging the radiation beam reflected by the information layer onto a detector, wherein the optical system incorporates a wavelength sensitive structure which compensates for a temperature-induced defocusing of the optical system.

Abstract: An optical information storage system has a multi-recording-layer record carrier and a scanner device for the carrier. The scanner produces a radiation beam which is compensated for spherical aberration for a single height of the scanning spot with the stack of layers. The height of the stack is determined by the maximum spherical aberration permissible for the system. The number of layers in the stack is determined by the minimum distance between layers, which depends on the crosstalk in the error signals due to currently unscanned layers.

Abstract: An optical device for scanning an optical record carrier (20) has a radiation source (25) that can emit two radiation beams of different wavelength along different optical paths (28, 29). The emitted radiation is focused on the record carrier and reflected back to a detection system (40). A beam combiner 43 is arranged in the optical path between the radiation source and the detection system for combining the two radiation beams on one optical path, thereby allowing the use of a single detection system for both radiation beams. The beam combiner includes a grating that passes one of the beams undiffracted and diffracts the other beam mainly in the first order. The profile of the grating lines show alternating slanting grooves and slanting lands.

Abstract: The invention relates to a data processing system comprising a computer having a memory for storage and retrieval of at least one application program embodying a pre-determined functionality, and for storage and retrieval of at least one data-file, which computer comprises a user interface for entertaining communication between the computer and a user of said computer, whereby the at least one application program comprises validation software for checking and enabling the operability of said application program in connection with the at least one data-file, and processing software for executing the said functionality in connection with the at least one data-file in dependence of said enabling by the validation software, whereby the validation software is executable separately and independent from the processing software.

Abstract: In an optical scanning device for scanning an optical record carrier (20) and comprising a radiation source (2), a beam splitter (8) arranged to pass a first portion (b3) of the source beam (b1) to the record carrier and a second portion (b5) to an intensity sensor (10), and a signal detector (24) in the path of the beam reflected by the record carrier, false radiation (b6) reflected by the signal detector can be prevented from reaching the intensity sensor by tilting the signal detector. A polarization filter (40) may be arranged in front of the intensity sensor to prevent false radiation reflected by the radiation source and by the signal detector from reaching the intensity sensor.

Abstract: The invention relates to an optical scanning device for scanning in a first mode a first information layer (111) of an information carrier and in a second mode a second information layer (112) of the information carrier. The optical scanning device comprises a radiation source (101) for generating a radiation beam (102), an objective system (105) for focussing an entrance beam on an information layer and an optical element (103) arranged between the radiation source and the objective system, for converting said radiation beam into a diverging entrance beam in the first mode and a converging entrance beam in the second mode.

Abstract: An optical scanning device for scanning an optical record carrier includes a radiation source and a beam splitter arranged to pass a first portion of the source beam to the record carrier, and a second portion to an intensity sensor. A signal detector is arranged in the path of the beam reflected by the record carrier. False radiation reflected by the signal detector can be prevented from reaching the intensity sensor by tilting the signal detector. A polarization filter may be arranged in front of the intensity sensor to prevent false radiation reflected by the radiation source and by the signal detector from reaching the intensity sensor.

Abstract: A radiation detector array for radial tracking error detection for a dual-wavelength optical scanning device. Three spot detectors (100, 102, 104) for conducting three spot radial tracking error detection at each of the two different wavelengths. Satellite spot detectors (102, 104) are divided into three detector elements and one switched depending on the wavelength currently being used for scanning.

Abstract: An optical device for scanning an optical record carrier (20) has a radiation source (25) that can emit two radiation beams of different wavelength along different optical paths (28, 29). The emitted radiation is focused on the record carrier and reflected back to a detection system (40). A beam combiner 43 is arranged in the optical path between the radiation source and the detection system for combining the two radiation beams on one optical path, thereby allowing the use of a single detection system for both radiation beams. The beam combiner includes a grating that passes one of the beams undiffracted and diffracts the other beam mainly in the first order. The profile of the grating lines show alternating slanting grooves and slanting lands.

Abstract: An optical scanning device for scanning a recordable optical disk (20) with a laser beam having a linear polarisation. A quarter wave plate (16) is used to alter the polarisation of the beam on reflection from the disk. A partially polarising beam splitter (8) is used and arranged such that a proportion of intensity of the incident beam passed is greater than a proportion of intensity of the reflected beam. A relatively high optical signal power at the disk (20) can be achieved for recording purposes whilst allowing the beam splitter (8) to be manufactured in a relatively efficient manner.

Abstract: An optical information storage system has a multi-recording-layer record carrier and a scanner device for the carrier. The scanner produces a radiation beam which is compensated for spherical aberration for a single height of the scanning spot with the stack of layers. The height of the stack is determined by the maximum spherical aberration permissible for the system. The number of layers in the stack is determined by the minimum distance between layers, which depends on the crosstalk in the error signals due to currently unscanned layers.

Abstract: In an optical scanning device for scanning an optical record carrier (20) and comprising a radiation source (2), a beam splitter (8) arranged to pass a first portion (b3) of the source beam (b1) to the record carrier and a second portion (b5) to an intensity sensor (10), and a signal detector (24) in the path of the beam reflected by the record carrier, false radiation (b6) reflected by the signal detector can be prevented from reaching the intensity sensor by tilting the signal detector. A polarization filter (40) may be arranged in front of the intensity sensor to prevent false radiation reflected by the radiation source and by the signal detector from reaching the intensity sensor.

Abstract: An optical information storage system has a multi-recording-layer record carrier and a scanner device for the carrier. The scanner produces a radiation beam which is compensated for spherical aberration for a single height of the scanning spot with the stack of layers. The height of the stack is determined by the maximum spherical aberration permissible for the system. The number of layers in the stack is determined by the minimum distance between layers, which depends on the crosstalk in the error signals due to currently unscanned layers.

Abstract: An optical scanning device for scanning a recordable optical disk (20) with a laser beam having a linear polarisation. A quarter wave plate (16) is used to alter the polarisation of the beam on reflection from the disk. A partially polarising beam splitter (8) is used and arranged such that a proportion of intensity of the incident beam passed is greater than a proportion of intensity of the reflected beam. A relatively high optical signal power at the disk (20) can be achieved for recording purposes whilst allowing the beam splitter (8) to be manufactured in a relatively efficient manner.

Abstract: A device for optically scanning an information plane having tracks. Radiation is supplied by a radiation source focused on the information plane by an objective system. The beam reflected by the information plane is incident on a dividing element, for example a grating which divides the beam into two halves along a dividing line. Two sub-gratings at both sides of the dividing line each form a detection beam from one half of the beam, which detection beams are detected each by a detector. A focus error signal is generated from the detector signals by forming a difference signal of the two detector signals and dividing this difference signal by the sum signal of the two detector signals. The focus error signal is relatively insensitive to the position accuracy of the detectors with respect to the detection beams.

Abstract: An optical information storage system has a multi-recording-layer record carrier and a scanner device for the carrier. The scanner produces a radiation beam which is compensated for spherical aberration for a single height of the scanning spot with the stack of layers. The height of the stack is determined by the maximum spherical aberration permissible for the system. The number of layers in the stack is determined by the minimum distance between layers, which depends on the crosstalk in the error signals due to currently unscanned layers.

Abstract: An optical information storage system has a multi-recording layer record carrier and a scanner device for the carrier. The scanner produces a radiation beam which is compensated for spherical aberration for a single height of the scanning spot with the stack of layers. The height of the stack is determined by the maximum spherical aberration permissible for the system. The number of layers in the stack is determined by the minimum distance between layers, which depends on the crosstalk in the error signals due to currently unscanned layers.