摘要:
The present invention relates to a domain expansion storage medium and manufacturing method with improved readout performance. The substrate of the storage medium and/or its storage layer is processed to define a predetermined shape of magnetic domains, adapted to the front of the thermal reading profile. In particular, reversed crescent shaped domains flipped in the track directions are defined. This allows improved resolution and jitter values.
摘要:
An optical scanning device for scanning a record carrier (22), the record carrier having an outer face (24), wherein the optical scanning device comprises a radiation source system (2) arranged to generate radiation (3); an objective system (20) having an exit face (24), the objective system being arranged between the radiation source system and the record carrier; a radiation detector arrangement for generating detector signals representing information detected in the radiation after interaction with the record carrier; and a position control system (42) for controlling a gap size of a gap between the exit face of the objective system and the outer face of the record carrier, the position control system providing for evanescent coupling of the radiation across the gap. The optical scanning device is arranged to process the detector signals to generate error signals suitable for controlling characteristics of the device during scanning of a record carrier, the error signals including a first error signal (E1) for use by the position control system for controlling the gap size. The optical scanning device is characterised in that the optical scanning device is arranged to generate a second error signal (E2), different to the first error signal, for use by the position control system for controlling the gap size.
摘要:
An optical data storage system for recording and/or reading, using a radiation beam, having a wavelength λ, focused onto a data storage layer of an optical data storage medium is described. The system comprises the medium having a cover layer that is transparent to the focused radiation beam, an optical head, including an objective having a numerical aperture NA, said objective including a solid immersion lens that is adapted for being present at a free working distance of smaller than λ/10 from an outermost surface of said medium. The optical head comprises a first adjustable optical element corresponding to the solid immersion lens, means for axially moving the first optical element and dynamically keeping constant the distance between cover layer and solid immersion tens, a second adjustable optical element, means for dynamically adjusting the second optical element for changing the focal position of the focal point of the focused radiation beam relative to an exit surface of the solid immersion lens. This achieves reliable read-out and writing during cover layer thickness variations. Further a method is described for controlling such a system.
摘要:
An optical pickup actuator for scanning an optical record carrier comprises a first section having an objective system and second section having an optical element with large position tolerances with respect to the objective system. For high bandwidth performance and/or low power dissipation a small movable actuated mass is preferred. A resilient member is connecting the second section to the first section.
摘要:
The present invention relates to a storage medium (10) comprising an information layer (11) including transparent and non-transparent areas in which the information is stored, and a magnetizable layer (12) intended to contain at least one magnetized area, which is temporarily created when a light spot is transmitted by a corresponding transparent area of the information layer. The present invention also relates to a reading device for reading information on such a storage medium (10). Said reading device comprises an optical element (23) for generating an array of light spots from an input light beam (21), a light spot being intended to temporarily create the magnetized area in the magnetizable layer (12) when passing through the corresponding transparent area of the information layer (11), and a magnetic sensor (24) comprising an array of sensor elements for detecting the at least one magnetized areas.
摘要:
A beamshaping optical stack (108), a light source and a luminaire is provided. The beamshaping optical stack (108) is to be optically coupled to a light emitting surface of a light emitter. The beamshaping optical stack (108) comprises a first light transmitting layer (120) and a second light transmitting layer (118). The second light transmitting layer (118) comprises a first side (110) which is optically coupled to the first light transmitting layer (120) to receive light from the first light transmitting layer (120). The second light transmitting layer (118) further comprises a second side (106) which is substantially opposite the first side (110) to emit the received light into another optical medium. The second light transmitting layer (118) further comprises a geometrical structure (116) at the second side (106) to obtain a decreasing light emission with increasing light emission angles (9a) with respect to a normal (112) to the first side (110). The first light transmitting layer (120) is of a first material having a first refractive index. The second light transmitting layer (118) is of a second material having a second refractive index. The first refractive index is lower than the second refractive index.
摘要:
Multi layer near-field optical recording using a moderate numerical aperture (NA) is superior to the high-NA (NA=2.0) first-surface single-layer technique. The use of very flat and thin spacer layers limits spherical aberration due to difference in layer depth. The thin spacer layers may have a high refractive index because their thickness allow for a relatively high absorption constant. This makes possible in principle an m-layer system, e.g. m=4, with NA=1.6 which may include a flat, protective cover layer. Further a medium for use in such a system is described.
摘要:
For optical data storage applications a near field optical system can be used. In near field optical systems an accurate alignment of a solid immersion lens with respect to a disc surface is crucial. The correction of a tilt between the lens and the disc is performed by use of auxiliary beams. By comparing the gap signal for the auxiliary beams the air gap height and disc tilt can be determined.
摘要:
An optical scanning device for scanning a record carrier (22), the record carrier has an outer face (24) and the optical scanning device comprises a radiation source system (2) arranged to generate a radiation beam; an objective system (20) having an exit face (76) and which is arranged between the radiation source system and the record carrier and provides for evanescent coupling of the radiation across a gap between the exit face of the objective system and the outer face of the record carrier; and a radiation detector arrangement for detecting radiation after interaction with the record carrier. The radiation detector arrangement is arranged to produce a tilt error signals (α, β) representing a tilt misalignment between the exit face of the objective system and the outer face of the record carrier. The radiation detector arrangement is arranged to produce the tilt error signal by detecting information in the radiation which is indicative of a variation in efficiency off the evanescent coupling across the exit face.
摘要:
Magneto-optical device comprising a magneto-optical read and/or write head with a coil (5), and a means for generating a laser beam (1), wherein the laser beam is passed through an aperture (12) in the coil (5) during operation, characterized in that the coil holder comprises a recess at or around the position of the optical center of the coil, and a lens (4) extends, viewed from the disk, behind the coil, overlapping the coil at least partly.