摘要:
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.
摘要:
Method of registering a running time on an information carrier, the information carrier comprising main data and subcode data, the running time being indicated in a subcode channel by a subcode time expressed in accordance with a predetermined format. A pseudo-running time is described by incrementing the subcode time in accordance with a pseudo-tempo, which is different from an actual tempo, the actual tempo representing a tempo in accordance with the actual running time.The invention further relates to an information carrier and an apparatus.
摘要:
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.
摘要:
An optical read unit is described for scanning a record carrier with a radiation-reflecting trackwise-arranged information structure. The read unit utilizes a diode laser which generates the read beam and also detects the information stored on the record carrier. The read unit is also provided with an opto-electronic system for detecting the position of the read spot relative to a track to be read and the position of the plane of focussing. The diode is mounted in a housing and the unit includes electromechanical apparatus for moving the housing in two perpendicular directions so as to correct the position of the read spot. The objective system for the formation of the read spot is of simple construction.
摘要:
A focussing error detection system is described for determining deviations between the plane of imaging of an objective system in an optical arrangement and the radiation-reflecting surface in said system. The apparatus comprises an optical element by means of which a radiation beam coming from the radiation reflecting surface is both rendered astigmatic and separated from a radiation beam which is directed to the radiation-reflecting surface. By the use of this element the number of components of the focussing-error detection system can be minimized and a compact construction of said system can be obtained.
摘要:
Running time is registered on an information carrier that includes main data and subcode data. The running time is indicated in a subcode channel by a subcode time expressed in accordance with a predetermined format. A pseudo-running time is described by incrementing the subcode time in accordance with a pseudo-tempo, which is different from an actual tempo, the actual tempo representing a tempo in accordance with the actual running time.
摘要:
A system for controlled reproduction of information according to the invention comprises an information carrier and a reading device. The information carrier contains information in blocks written in a track. The information carrier has reference patterns which divide the track into sectors for writing the information blocks, and auxiliary information written in the reference patterns. The auxiliary information is related to the information, for example, a decoding key, access code or digital signature. The reading device comprises a demodulation means for recovering both the information and the auxiliary information. The device may include means for processing the information and/or auxiliary information in dependence on the auxiliary information. Since the auxiliary information cannot be transferred to an illegal copy, this copy is unusable.
摘要:
A record carrier is disclosed having an optically readable information structure comprising trackwise arranged information areas, as well as an apparatus for reading said record carrier. By using two mutually perpendicularly polarized beams components for reading and by giving the information areas of adjacent track portions a different geometries such that areas of one geometry can be read in an optimum manner by only one of the beam components and is virtually not observed by the other beam component, the track distance can be reduced without increasing the crosstalk, so that the information content of the record carrier is increased.
摘要:
A next generation of high speed CD-RW discs for high speed recording (4×-10×) need a new write strategy, which is not suited for recording at lower speeds (1×4×). Existing CD-RW recorders may accept these discs and make recordings according to existing write strategies. This will result in unreadable discs. To prevent this, a Power Calibration Area (PCA) and a Program Memory Area (PMA), both needed for recording, are hidden for the existing recorders. As a result the disc will be rejected. In a method wherein an absolute time reference (ATIP) is applied on the disc, the start locations of said areas being determined by a fixed time offset relative to a subsequent Lead-in area, an embodiment of the invention is obtained by making the PCA and PMA untraceable by introducing and Absolute Time in Pre-Groove (ATIP) time code jump of for instance one minute just before the Start time of the Lead-in area. Another embodiment is obtained by introducing the absolute Time in Pre-Groove (ATIP) time code jumps between a Test Area and a Count Area of the program calibration area (PCA).
摘要:
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.