摘要:
A method for manufacturing a disc includes the steps of performing laser exposure of an inorganic resist master on which a photosensitive layer is formed using an inorganic material, which protrudes in an exposed region, and a surface coat layer is formed on the surface of the photosensitive layer in order to control the shape of protrusion, transferring the shape of protrusion formed by the laser exposure on the inorganic resist master to produce a stamper on which a portion corresponding to the shape of protrusion is a depression, forming a resin substrate using the stamper so that a portion corresponding to the shape of protrusion is a protrusion, and forming a predetermined layer structure on the resin substrate to produce an optical disc.
摘要:
An optical-disc manufacturing method including the steps of: fabricating a pre-exposure disc master by forming, on a substrate, a heat accumulation layer having a thickness of 17% or less of a recording-laser wavelength and forming an inorganic resist layer; performing exposure of a recording-signal pattern having pits and spaces with respect to the inorganic resist layer of the disc master, by performing recording-laser light irradiation; fabricating a disc master having a pit-array shape having pits and spaces, by performing development processing after the exposure; manufacturing a stamper to which the pit-array shape is transferred, by using the disc master having the pit-array shape; and manufacturing an optical disc having a predetermined layer structure including a recording layer to which the pit-array shape of the stamper is transferred and in which a silver or silver-alloy reflective film is formed on the pit-array shape.
摘要:
An optical recording medium wherein characters can be easily recognized on an optical disk irradiated with a light through a light transmitting layer and a method of producing the same are provided. In an optical disk of a type that an optical recording layer is irradiated with a light through a light transmitting protective layer, dealing with a larger capacity, wherein one main surface of a medium substrate 15 is divided to a signal portion SG and a character portion CA, a signal portion uneven shape (15p) is formed on the signal portion SG and a character portion uneven shape (15p) is formed on the character portion CA, and depths of the signal portion uneven shape and the character portion uneven shape are 25 nm or less. Here, it is configured that characters are recorded to be able to be read as normal characters when looking from the medium substrate 15 side (Y-direction) by outlines of a region formed with the character portion uneven shape on the character portion CA.
摘要:
The S/N ratio is improved for recording data to grooves (2-1,2-2) of an optical disc so that as much information as possible can be recorded at the lowest possible frequency band. An optical disc using wobble patterns to record different information has a first groove (2-1) having a first wobble pattern (22) in which one wobble period has a sharp rising edge and a gradual falling edge; and a second groove (2-2) having a second wobble pattern (24) in which one wobble period has a gradual rising edge and a sharp falling edge. Each of the first and the second wobble pattern is represented by a first fundamental and a second harmonic of a Fourier series. The polarity of the second harmonic, which is an even harmonic, of the second wobble pattern is opposite that of the first wobble pattern. A method for manufacturing this optical disc is also provided.
摘要:
A data area to record and/or reproduce data and an eccentricity measuring area 14 in which a groove area formed with spiral grooves and a planer mirror area are spatially alternately arranged are provided for a disc substrate. A width of groove area formed in the eccentricity measuring area, a width of mirror area, and an interval between the grooves in the groove area are selected so that a conventional mechanical characteristics measuring apparatus can track a plurality of grooves formed in the groove area as if the grooves were a single groove.
摘要:
The S/N ratio is improved for recording data to grooves (2-1,2-2) of an optical disc so that as much information as possible can be recorded at the lowest possible frequency band. An optical disc using wobble patterns to record different information has a first groove (2-1) having a first wobble pattern (22) in which one wobble period has a sharp rising edge and a gradual falling edge; and a second groove (2-2) having a second wobble pattern (24) in which one wobble period has a gradual rising edge and a sharp falling edge. Each of the first and the second wobble pattern is represented by a first fundamental and a second harmonic of a Fourier series. The polarity of the second harmonic, which is an even harmonic, of the second wobble pattern is opposite that of the first wobble pattern. A method for manufacturing this optical disc is also provided.
摘要:
There are provided an optical recording medium and a method of manufacturing the optical recording medium. The optical recording medium has a pattern of microscopic depressions and projections molded thereon with a high fidelity of replication. The method of manufacturing the optical recording medium comprises the steps of forming a photoresist layer on a substrate; exposing a predetermined area of the photoresist layer formed on the substrate to form a plurality of trains of depressions in the photoresist layer; removing the photoresist layer between the adjoining depression trains to form a master; plating the master with a metal; separating the metal coating to form a master stamper; replicating the master stamper repeatedly an odd number of times to form a mother stamper; replicating the mother stamper to form a resin substrate; and forming at least a light-transparent layer on a surface of the resin substrate on which the mother stamper is replicated. The method can mold a pattern of microscopic depressions and projections with a high accuracy.
摘要:
A novel optical disc which, while having interchangeability with a conventional MD or MD data, has a capacity far exceeding the capacity of these optical discs, and an optical disc device. The optical disc and the optical disc device take into account the constraints of the skew accompanying the increased recording density. By setting the jitter produced when recording random pattern signals on one track only to not more than 8.4% and by setting jitter increase on recording signals also on both side neighboring tracks to not more than 4.9%, the skew margin in the radial direction of not less than ±0.7° and that in the running direction (circumferential direction) of not less than ±0.6° are assured.
摘要:
This invention relates to a stamper for optical disc and a method for manufacturing an optical disc by using this stamper. A photoresist is applied to a substrate (2) and this photoresist is exposed, developed and then transferred to form a disc master which has a recess/protrusion pattern formed on its one side. The one side of the disc master (20) is etched to narrow the width of a protruding part constituting the recess/protrusion pattern, and the recess/protrusion pattern of the disc master (20) with the reduced width of the protruding part is transferred to form a stamper (30). The recess/protrusion pattern provided on the stamper (30) is transferred to form a predetermined pattern on a substrate of an optical disc.
摘要:
An optical recording medium according to the present invention includes a data recording area forming a double spiral structured track having spiral recording tracks each formed of a groove and a land adjacent to the groove, and a reproduction only area forming a single spiral structured track consisting of a pit row.