Abstract:
An optical data storage medium (10) is described for read out using a focused radiation beam (19) with a wavelength λ sand a Numerical Aperture NA. The medium has a substrate (11) and a first stack of layers named L0 (12) comprising a first information layer and optionally at least one further stack of layers named Ln (13), comprising a further information layer. A radiation beam (19) transparent spacer layer (14) is present between each of L0 and Ln. A transmission stack named TS0 with a thickness dTS0 contains all layers between L0 (12) and an entrance face (16) of the medium (10). A transmission stack named TSn with a thickness dTSn contains all layers between Ln (13) and the entrance face (16). The maximum deviation of dTS0 and when applicable dTSn does not exceed a predetermined value DEVdTS0 or DEVdTSn, measured over the information area of the medium (10) and this value is set in dependency of λ and NA. In this way a reliable read out of the information layer(s) without the need for dynamic spherical aberration correction is achieved.
Abstract:
A dual-stack optical data storage medium (20) is described for read out using a focused radiation beam (29) with a wavelength of 400-410 nm and a Numerical Aperture (NA) of 0.84-0.86. The medium has a substrate (21) and a first stack of layers named L0 (22) comprising a first information layer and a second stack of layers named L1 (23), comprising a second information layer. A radiation beam (29) transparent spacer layer (24) is present between L0 and L1. A transmission stack named TS0 with a thickness dTS0 and an effective refractive index nTS0 contains all layers between L0 and an entrance face (26) of the medium (20). A transmission stack named TS1 with a thickness dTS1 and an effective refractive index nTS1 containing all layers between L1 and the entrance face (26). The spacer layer (24) has a thickness selected from the range 20-30 μm, the thickness dTS0 in dependence on the refractive index nTS0 and the thickness dTS1 in dependence on the refractive index nTS0 are within a specified area. In this way a reliable read out of both the first and the second information layer of respectively L0 and L1 is achieved.
Abstract:
In an optical scanning device (10) capable of scanning an information plane of an optical record carrier (5) of different types such as BD, DVD and CD, the diameter of the radiation spot on the detector (7) is dependent on the numerical aperture of the objective system (4) that is used for scanning the record carrier An optimal design of the optical detection system for scanning a BD, result in a small radiation spot for the other types such as DVD and CD. By implementing an optical element (13) that increases the diameter of the radiation spot in the situation a DVD or CD is scanned, the influence of stray light is reduced and the tracking signals are improved
Abstract:
A record carrier comprises three layers that react with each other when irradiated to form a mark on the record carrier. The three layers are separated by a two separating layers that prevent direct contact of the three layers thus providing stability to the record carrier. By irradiating one or both separating layers a region of those separating layers is destroyed or altered whereby an opening is created and the reaction of the layers adjacent to the separating layer is no longer prevented in that region and a mark can be formed. Since either one or two reactions can take place if one or both separating layers are destroyed or altered multiple reflection levels for a mark can be obtained, thus enabling multilevel recording where a single mark can represent more information compared to the situation where only two reflection levels can be obtained. The size of the resulting opening determines the size of the mark and can thus be used to create a very small mark allowing high density recordings.
Abstract:
The present invention relates to a writable optical record carrier and a method of writing information on such a writable optical record carrier. The record carrier comprises a substrate carrying a recording stack which recording stack comprises, in this order, a recording layer and an absorption layer. The recording layer is essentially transparent for an incident light beam, and comprises material which changes its optical characteristics when heated. The first absorption layer converts the incident beam to heat thereby indirectly changing the optical characteristics of the recording layer material. The method comprises the steps: positioning a writing unit at a predetermined position, generating the beam by means of the writing unit, at least partially absorbing the beam in the first absorption layer, thereby producing a first spot of heat, conducting the heat towards the recording layer, and thereby locally changing the optical characteristics of the recording layer material.
Abstract:
An electronic circuit comprises a memory matrix (60) with rows and columns of memory cells (16). First row conductors (10, 12) are provided for each of the rows. Second row conductors (12) are provided for successively overlapping pairs of adjacent rows. Column conductors (14) are provided for each of the columns. Each of the memory cells (16) comprises an access transistor (160), a node (166) and a first and second resistive memory element (162, 164). The access transistor (160) is preferably a vertical transistor having a control electrode coupled to the first row conductor (10) of the row of the memory cell (16), a main current channel coupled between the column conductor (14) for the column of the memory cell (160) and the node (166). The first and second resistive memory element (162, 164) are coupled between the node (166) and the second row conductors (12) for the pairs of rows to which the memory cell belongs.
Abstract:
The present invention relates to a method of writing information on an optical recording medium (10 to 38), the optical recording medium having at least one data layer (40) for storing data readable by use of an optical readout device and at least one label layer (42) for storing visible information, the method comprising the steps of: focusing a first wavelength laser beam (44 to 58) onto the at least one data layer for writing data on the data layer, and focusing a second wavelength laser beam (60 to 78) onto the at least one label layer for writing visible information on the label layer, thereby a laser spot size being usable that is also employable when using the second wavelength laser beam for writing data on a data layer for storing data readable by use of an optical readout device. The present invention further relates to an optical recording medium and to a method of manufacturing an optical recording medium.
Abstract:
In an optical scanning device (10) capable of scanning an information plane of an optical record carrier (5) of different types such as BD, DVD and CD, the diameter of the radiation spot on the detector (7) is dependent on the numerical aperture of the objective system (4) that is used for scanning the record carrier An optimal design of the optical detection system for scanning a BD, result in a small radiation spot for the other types such as DVD and CD. By implementing an optical element (13) that increases the diameter of the radiation spot in the situation a DVD or CD is scanned, the influence of stray light is reduced and the tracking signals are improved
Abstract:
A recordable optical record carrier is provided comprising a recording dye layer, whereby said recording dye layer (111) comprises at least two organic dye materials being absorptive at different wavelengths. Further, a method for writing on such a recordable optical record carrier is proposed. According to the method marks representing the data are written via a writing laser beam at a first predetermined wavelength according to a writing strategy providing a channel bit length and a mark width appropriate for read-out by a beam of electromagnetic radiation at a second predetermined wavelength being different from said first predetermined wavelength.
Abstract:
The present invention relates to a writable optical recording medium (500), and in particular to a write-once optical record carrier comprising a substrate (520) carrying a recording stack (510) which recording stack comprises a recording layer (516), made of PEDOT and/or derivatives thereof.