Patent classifications
G11B7/261
Displacement detection device
A displacement detection device is capable of stably and accurately detecting an amount of displacement. A polarization maintaining fiber has a length not to be equal to a length obtained by dividing, a product of an integral multiple of twice a length of a resonator times a refractive index of the resonator and a beat length obtained from a difference between propagation constants of two polarization modes, by a wavelength of the light source, is selected from a range including a length equal to the above length. The polarization maintaining fiber includes multiple polarization maintaining fibers fitted to each other by removable connectors.
CYLINDRICAL BASE, MASTER AND MASTER MANUFACTURING METHOD
Provided are a cylindrical base, a master and a method for manufacturing a master enabling a uniform transfer of a fine pattern. A cylindrical base of a quartz glass having an internal strain in terms of birefringence of less than 70 nm/cm is used. A resist layer is deposited to an outer circumference surface of this cylindrical base, a latent image is formed on the resist layer, the latent image formed on the resist layer is developed and the pattern of the developed resist layer is used as a mask for etching to form a structure including concaves or convexes arranged in a plurality of rows on the outer circumference surface of the cylindrical base.
Method for producing a high definition analogue audio storage medium
The present invention provides a computer-implemented method and an apparatus for manufacturing an analogue audio storage medium wherein digital audio data is converted into topographical data representing an analogue translation of the digital audio data, and a laser beam is selectively applied to a substrate to form a physical imprint of the topographical data on the surface of the substrate to create an analogue audio storage medium. The medium may be directly playable on a conventional playback device such as a record player and/or used to mould further playable mediums. The invention thereby enables more efficient manufacturing of e.g. vinyl records and consistently ensures a much higher quality of analogue audio.
Cylindrical base, master and master manufacturing method
Provided are a cylindrical base, a master and a method for manufacturing a master enabling a uniform transfer of a fine pattern. A cylindrical base of a quartz glass having an internal strain in terms of birefringence of less than 70 nm/cm is used. A resist layer is deposited to an outer circumference surface of this cylindrical base, a latent image is formed on the resist layer, the latent image formed on the resist layer is developed and the pattern of the developed resist layer is used as a mask for etching to form a structure including concaves or convexes arranged in a plurality of rows on the outer circumference surface of the cylindrical base.
Method and device for irradiating spots on a layer
For irradiating a layer a radiation beam is directed and focussed to a spot on the layer, relative movement of the layer relative to the lens is caused so that, successively, different portions of the layer are irradiated and an interspace between a surface of the lens nearest to the layer is maintained. Furthermore, at least a portion of the interspace through which the radiation irradiates the spot on the layer is maintained filled with a liquid, the liquid being supplied via a supply conduit. At least a portion of the liquid fills up a recess through which the radiation irradiates the spot.
Method for manufacturing information recording medium
The same digital data is recorded with highly integrated manner on a plurality of media able to durably hold information over long-term. A minute graphic pattern indicating data bit information is drawn on a resist layer formed on a quartz glass substrate by exposing a beam and developed so as to prepare a master medium (M1), which comprises the quartz glass substrate having a minute recess and protrusion structure formed by etching where the remaining resist are used as a mask (FIG. (a)). The recess and protrusion structure recorded on the master medium (M1) is shaped and transferred onto a flexible recording medium (G2) on which a UV curable resin layer (61) is formed, whereby an intermediate medium (M2) is prepared (FIGS. (b)-(d)). The inverted recess and protrusion structure transferred to the intermediate medium (M2) is shaped and transferred onto a recording medium (G3) comprising a quartz glass substrate (70) on which a UV curable resin layer (80) is formed, whereby a reproduction medium (M3) having the same recess and protrusion structure as that of the master medium (M1) is prepared (FIGS. (e)-(h)). In shaping and transferring process, the media are separated using the flexibility of the intermediate medium (M2).
Displacement Detection Device
A displacement detection device is capable of stably and accurately detecting an amount of displacement. A polarization maintaining fiber has a length not to be equal to a length obtained by dividing, a product of an integral multiple of twice a length of a resonator times a refractive index of the resonator and a beat length obtained from a difference between propagation constants of two polarization modes, by a wavelength of the light source, is selected from a range including a length equal to the above length. The polarization maintaining fiber includes multiple polarization maintaining fibers fitted to each other by removable connectors.
Replication tools and related fabrication methods and apparatus
Durable seamless replication tools are disclosed for replication of seamless relief patterns in desired media, for example in optical recording or data storage media. Methods of making such durable replication tools are disclosed, including preparing a recording substrate on the inner surface of a support cylinder, recording and developing a relief pattern in the substrate, creating a durable negative relief replica of the pattern, extracting the resulting durable tool sleeve from a processing cell, and mounting the tool sleeve on a mounting fixture. Apparatus are disclosed for fabricating such seamless replication tools, including systems for recording a desired relief pattern on a photosensitive layer on an inner surface of a support cylinder. Also disclosed are electrodeposition cells for forming a durable tool sleeve having a desired relief pattern. The replication tool relief features may have critical dimensions down to the micron and nanometer regime.
Heat-reactive resist material, mold manufacturing method, mold, development method and pattern formation material
A heat-reactive resist material contains copper oxide, and silicon or silicon oxide, and is formed so that the content of silicon or silicon oxide in the heat-reactive resist material is 4.0 mol % or more less than 10.0 mol % in terms of mole of silicon. A heat-reactive resist layer is formed using the heat-reactive resist material, is exposed, and then, is developed with a developing solution. Using the obtained heat-reactive resist layer as a mask, dry etching is performed on a substrate with a fluorocarbon to manufacture a mold having a concavo-convex shape on the substrate surface. At this point, it is possible to control a fine pattern comprised of the concavo-convex shape.
Data storage medium and manufacturing method thereof, data storage medium, data read out apparatus and data read out method
A data storage medium includes a convexoconcave structure formed in a storage area which is set on a first surface of a quartz glass substrate. The storage area includes a plurality of unit storage areas which are arrayed at least in one direction, and non-data storage areas which are disposed between the unit storage areas, which are adjacent to each other. The convexoconcave structure includes unit data patterns, address patterns and boundary patterns. The unit data patterns are formed in the plurality of unit storage areas respectively in the array sequence of the unit storage areas, and the address patterns are formed in the non-data storage areas so as to correspond to each of the unit storage areas in which the unit data patterns are formed respectively.