Abstract: The data recording device comprises a two-dimensional array of microdots of nanometric dimensions arranged facing a storage medium. The storage medium comprises a sensitive area preferably comprising a flexible membrane and extended at its periphery by a flexible fixing membrane. The sensitive area of the storage medium is thus flexibly fixed to an external frame, allowing movement of the sensitive area in its plane and perpendicularly to its plane. The microdots are preferably formed on a convex front face of a substrate, enabling contact between each of the microdots and the sensitive area to be ensured in all cases. The radius of curvature of the convex surface is preferably comprised between 0.5 m and 5 m.

Abstract: A flexible optical disk, includes a disk substrate, wherein a rigidity of the disk is equal to or more than 5 Pa and equal to or less than 5000 Pa where the rigidity is defined as Young's modulus of the disk×(thickness of the disk/radius of the disk)3.

Abstract: The invention concerns a data recording device comprising a two-dimensional array of microtips (3), whereof the apex is generally of nanometric dimensions arranged opposite a storage medium consisting of a flexible diaphragm (2) borne by a frame (1) forming a plurality of cells. At least one microtip (3) is associated with each cell. Said device enables the dispersion in the height of the microtip to be compensated. In order to eliminate edge effects, the flexible diaphragm (2) may include first and second elementary diaphragms, separated by a network of spacer elements, laterally offset relative to the frame. In an alternative embodiment, an array of flexible plates, separated from the diaphragm by a two-dimensional array of spacer studs, may be used for subdividing each large-size cell into a plurality of elementary cells, each associated with at least one microtip.

Abstract: The flexible membrane comprises at least one thin layer with a plurality of indentations formed therein, wherein bearing points for actuating elements are disposed between said indentations in order to locally deform the membrane. The thus open-worked membrane is more flexible in a cross direction. The open-worked membrane can act as a support for the recording data, cooperating with a micro-point bi-dimensional network.

Abstract: Optical recording articles, such as tapes, and methods of making and using such articles are disclosed.

Abstract: Constructed is an optical recording medium which is so formed as to have excellent surface flatness and with respect to which information is recorded or reproduced with the use of a near-field optical system. The optical recording medium is one which performs at least one of recording and reproduction of information by irradiation of light. The optical recording medium has a substrate 1 which has fine concavities and convexities 2 formed on the surface on a side where irradiation of light is performed, and a formed film layer having at least a recording layer and having a fine concavities and convexities surface reflecting the fine concavities and convexities 2 in itself.

Abstract: An optical disk of the type rotated by a spindle positioned in a centrally-located hole, and including a disk body including an annular data area, and a centrally-located, integrally-formed annular web positioned radially inward from the annular data area and covering a hole formed in the disk body. The annular web is formed sufficiently thin to be deflected upwardly out of the plane of the disk body by the spindle during placement on the spindle and during rotation. The web may be broken away from the disk, or made sufficiently thin and resilient that it will deform upwardly when placed on the spindle and resume its former position when removed.

Abstract: The method of manufacturing an optical recording medium, according to the present invention, is a method of manufacturing an optical recording medium, in which a resin layer is formed by spin-coating a coating liquid (R) on a substrate (D) having a central portion thereof formed with a central mounting hole (1a), and the method comprises causing a rubber chuck (14) that is capable of being elastically deformed at least in radial directions and thereby closing the central mounting hole of the substrate, to undergo elastic deformation to perform chucking, whereby the substrate (D) is fixed to the turntable (12), and after dropping the coating liquid (R) onto a central portion of the rubber chuck (14), causing the turntable (12) to rotate to thereby spin-coat the coating liquid (R). This makes it possible to reliably and easily form excellent resin layer while enhancing productivity.

Abstract: A data storage medium includes an information carrier wound onto a winding core in a spiral manner for optically readable information units. The winding core is configured in a spiral manner on its outer contour and has a step. The height of the step is matched to the thickness of the information carrier. The inner end of the information carrier rests on the winding core at the step or in the area of the step.

Abstract: A data storage medium (1) has an optical information carrier which comprises a polymer film (11) wound in spiral fashion in a plurality of plies (10), through which information can be read from a preselected polymer film ply (10) and, optionally, written to a preselected polymer film ply (10). A varnish layer (12) set up as an adhesion layer is disposed between adjacent polymer film plies (10).

Abstract: Optical recording articles, such as tapes, and methods of making and using such articles are disclosed.

Abstract: A system and method dispense resin between substrates. A top substrate device holds a top substrate concave up. A bottom substrate device holds a bottom substrate concave down. A resin dispensing device has a needle and dispenses a trajectory of resin defined by an arc having a tangent that touches a tangent of a concave-up-shaped top substrate. The top substrate device may be arranged to include a dampening mechanism to cause a dampened release of the top substrate. Moreover, the top substrate device may be arranged to hold a top substrate so that the top substrate has a continuous concave-up shape extending from a center portion of the top substrate to its outer diameter, and the bottom substrate device may be arranged to hold a bottom substrate so that the bottom substrate has a continuous concave-down shape extending from a center portion of the bottom substrate to its outer diameter.

Abstract: Flexible digital optical media, such as optical tapes, are provided with an aqueous-applied backing layer which provides excellent performance with regard to runnability, scratch resistance, abrasion resistance, frictional properties and curl characteristics. The backing layer comprises a film-forming water-dispersible polymeric binder and water-dispersible static-dissipative filler particles and a water-dispersible lubricant is either incorporated within the backing layer or forms a thin film over the surface of the backing layer.

Abstract: The present invention provides a method for internally damping a rotatable storage article which is subject to resonant vibrations. More specifically, the present invention provides a method of improving the damping properties of a rotatable storage article by introducing a viscoelastic material as an inner layer(s) of the rotatable storage article. The invention also provides the damped rotatable storage articles themselves.

Abstract: There is disclosed a flexible optical recording element comprising a flexible support having thereon, in order, an SbInSn phase-change alloy optical recording layer and an overcoat layer, the overcoat layer being a silicon oxide layer having an index of refraction greater than about 1.8 at about 800 nm wavelength and a thickness of about .lambda./4, where .lambda. is the wavelength at which the element is read. The element of the invention provides for an advantageous optical tape with a well adhered abrasion resistant overcoat which also provides for excellent corrosion resistance.

Abstract: A removable disk system includes a disk which can be recorded on both surfaces thereof and a disk drive for recording input data on tracks on both surfaces of the disk. The disk drive includes head means having two heads for recording information on both surfaces of the disk, the disk is a selectively replaceable disk on which servo information for positioning the head is recorded, the head means is formed with a gimbal structure having liners for holding the disk therebetween by pressing the recording surfaces thereof towards each other and a symmetrical member for moving the heads towards the flexible disk held between the liners from both sides thereof and setting the heads in contact with the flexible disk and the liners maintain the contact state between the heads and flexible disk set up by the gimbal structure and the contact position is defined by the servo information.

Abstract: The invention relates to a process for producing supports intended for the optical recording and reading of information. A layer containing a diazo compound is deposited onto a metallized substrate. Recording is obtained by exposing the support to light through a mask, the exposed zones of the layer of diazo compound being decomposed. Dry development in ammonia vapors shows up transparent zones and opaque zones corresponding to the information.

Abstract: Apparatus for fixturing an optical recording disc in a DRAW recording machine comprising a hub having a conical shoulder for receiving and locating the disc center opening, and an axially facing shoulder for nesting support of the recording disc. A retaining ring encircles the disc periphery and has an inwardly oriented lip for capturing the disc periphery. A resilient snubber of elastomeric construction extends from the hub to the ring and has a roughened axially facing surface spaced from the opposing surface of the disc. A knob, including a torque-isolating thrust bearing, clamps the hub to the drive spindle of a recording apparatus. In operation, the snubber and air space between the snubber and disc cooperate to dampen vibration of the recording disc for enhanced accuracy and reliability of the recording process.

Abstract: Stretched surface recording disk (SD) 10 comprises an annular support 12 having raised annular ridges 42 and 28 at its inside and outside diameters 22 and 30 with a base portion 24 in between the two ridges, and an annular recording medium film 14 held in radial tension and stretched across the base portion by adhering the film to attachment surfaces 48 and 36 near the inside and outside diameters respectively. The SD is annealed twice duringmanufacture to relieve stress in the stretched film 14. This annealing results in SD essentially free from track anisotropy and stress distribution anisotropy in the plane of the disk. As a result, data tracks are more stable than in previous SD, track density can be greater, and the SD is generally more reliable.

Abstract: In an information recording medium having an air-sandwich structure comprising two disc-shaped substrates opposed to each other at a given space by interposing therebetween a ring-shaped inner spacer and a ring-shaped outer spacer and a recording layer for writing and/or reading information with laser beam which is provided on the inner surface of at least one substrate, the improvement in which at least one spacer is an adhesive-retainable spacer comprising a ring portion of protecting circumferences of the substrates and a protruding ring portion of arranging the two substrates apart, the latter ring portion protruding from a side of the protective ring portion and comprising a front portion for defining the space between the substrates and a stem portion being thinner than the front portion for retaining an adhesive, whereby an excessive adhesive or a volatile material of the adhesive is discharged through a space between the substrate and the stem portion of the protruding ring portion.

Abstract: An optical floppy disk system is described in which the optical disk is enclosed in a flexible housing which is optically transparent. Both the optical disk and its protective housing can be made at very low cost from inexpensive materials. The disk is enclosed within the protective housing and the housing and disk rotate as a unit during operation. The protective housing does not adversely affect the optics of the system.

Abstract: A recording medium having an air-sandwich structure comprising two disc-shaped substrates opposed to each other at a given distance by interposing therebetween a ring-shaped inner spacer and a ring-shaped outer spacer and a recording layer for writing and/or reading information with laser beam which is provided on the inner surface of at least one substrate,characterized in that the distance between said two substrates satisfies the following expression (I): ##EQU1## wherein h is the distance in mm between two substrates, E.sub.1 and E.sub.2 are each a Young's modulus (in kg/mm.sup.2) of each substrate, l is the distance (in mm) between the inner spacer and the outer spacer, and t.sub.1 and t.sub.2 are each the thickness (in mm) of each substrate.

Abstract: An unconstrained removable protective cover for optical disks. With this apparatus a transparent protective cover can be mounted to an optical information recording disk wherein the different thermal expansion coefficients of the disk and the protective cover will not result in read write errors due to warping of the protective cover. An inner spacer ring is fixedly bonded to the inner diameter of the disk substrate and the protective cover. However, on the outer perimeter of the disk, a U-shaped spacer ring is fitted thereon and fixedly mounted to the outer perimeter of the transparent protective cover. This allows the transparent protective cover to expand and contract relative to the disk substrate by lateral movement of the spacer ring relative to the disk, without warping of the protective covering. A plurality of methods of mounting the outer spacer ring to the protective covering are disclosed.

Abstract: A device is disclosed for clamping disk assemblies in a manner to impart constant tension to a support web and cover sheet, while assuring easy and quick loading and unloading of the assembly. The optical disk assembly includes a web assembly including a flexible disk-shaped support web and preferably an opposed cover sheet. An annular retaining ring engages the web assembly around its periphery. The support web carries a record layer with an information storage region. The optical disk assembly is mounted on a reference structure. The web assembly is drawn over an annular locating surface integral with the reference structure to subject the web assembly to circumferentially-symmetric tension. The tension may be constant or, in some embodiments of the invention, may be changeable from a low "storage" tension to a higher "operating" tension. Clamping elements are movable radially over the optical disk assembly from a retracted position.

Abstract: An optical disk assembly includes a web assembly having a flexible disk-shaped support web carrying a record layer. The support web has an information storage region. A pair of annular retaining ring members engage opposite sides of an annular peripheral region of the web assembly to clamp the support therebetween are formed from malleable stock material which is deformed during assembly of the optical disk assembly to provide a locking interfit therebetween with the peripheral region of the web assembly interleaved between the ring members. The peripheral region of the support is wrapped about an annular reference surface of one ring member and is pushed into an annular recess with undercut area in that ring member. The other ring member is deformed into the recess undercut.

Abstract: An optical disc assembly includes a flexible disc-shaped support carrying a record layer. The support has an information storage region. A pair of annular retaining ring members engage opposite sides of an annular peripheral region of the support as the ring members close together to clamp the support therebetween. The peripheral region of the support is wrapped about an annular reference surface of one ring member and is pushed into an annular recess in that ring member. Cooperative surfaces on the ring members provide a locking interfit therebetween with the peripheral region of the support interleaved between the ring members.

Abstract: An optical disk unit, of the kind having a record element and a flexible cover sheet that are attached around an outer periphery in a manner providing an outer spacing and a generally enclosed inter-space therebetween, has an improved construction which significantly reduces the likelihood of contact between the record element and cover sheet. Central spacing means provide a central sheet-to-element spacing that is significantly larger than said outer spacing and vent means, into and out of the inter-space cause a reduction in the spacing between the record portion of the element and the cover sheet during write/read operation. The air flow through the vent means also reduces the formation of visible debris in the enclosed record element/cover sheet inter-space.

Abstract: An optical disc structure including two resilient disc members which are bonded together adjacent their outer peripheries and which include an air channel allowing communication between the chamber formed between the discs and the atmosphere. An information layer is formed on the inner surface of at least one of the members. When the members are spun, a pressure differential is caused tending to push the two members apart, thereby assuring that one member will not contact the information layer formed on the other member and that the two members will not be close enough together to cause optical interference.

Abstract: An optical disk assembly includes a flexible disk-shaped support carrying a record layer. The support has an information storage region. An annular retaining ring engages the annular peripheral region of the support. The support, and preferably a cover sheet, are captured between the outer annular reference ring member and an inner annular reference ring member which has been conically deformed to spring toward the outer ring member.

Abstract: An optical disk assembly includes a web assembly having a flexible disk-shaped support web carrying a record layer. The support web has an information storage region. A pair of annular retaining ring members engage opposite sides of an annular peripheral region of the web assembly to clamp the support therebetween. The peripheral region of the support is wrapped about an annular reference surface of one ring member and is pushed into an annular recess with undercut area in that ring member. The other ring member is formed from a malleable ring, such as an annular tube, which is deformed into the recess undercut to provide a locking interfit therebetween. The peripheral region of the web assembly is interleaved between the ring members.

Abstract: A methacrylate resin composition for optical information recording medium, excellent in releasability from mold, consisting of (A) 100 parts by weight of a methacrylate resin and (B) 0.1 to 3.0 parts by weight of a surface active agent having a fluoroalkyl group.

Abstract: An optically readable storage disc comprises a transparent substrate 1 on which a recording layer 2 is deposited which can be modified locally by means of a radiation beam, which recording layer is covered by a cover disc 3 which is secured to the substrate in a gas-tight manner at some distance from the part of the recording layer which is intended for recording, so that a sealed space 4 is enclosed between the substrate 1 and the cover disc 3. The cover disc 3 will be deformed to the greatest extent under the influence of differences between the gas pressure in the sealed space 4 and the barometric pressure because its resistance to deformation is substantially smaller, so that deformation of the substrate 1 is substantially precluded.

Abstract: A methacrylic resin having reduced water absorption properties, useful in optical instruments and as information recording substrates, is produced by polymerizing a mixture consisting of (A) 50 to 85% by weight of a methyl methacrylate, (B) 15 to 50 by weight of a cyclohexyl methacrylate and (C) 0 to 30% by weight of the other copolymerizable with said monomer (A) and (B), or partially polymerized product thereof.

Abstract: Optical disc write/read apparatus and systems of the type having a flexible record disc and turntable which interface in a manner forming a generally enclosed space between record portions of the disc and opposing turntable portions is provided with inner and outer ventilation means which effect a continuous, controlled air flow through said space during write/read operations.

Abstract: This disclosure relates to an optical disk unit with two states in which the web assembly is in different circumferentially-symmetric tensions. One tension is sufficiently great to provide the desired degree of planarity when used with write/read apparatus. The other tension is significantly reduced, keeping the web assembly materials well below their elastic limits to reduce tension and prolong product life. The optical disk unit includes a flexible disk-shaped web assembly including a support web and preferably an opposed cover sheet. An annular retaining ring engages the web assembly around its periphery. The support web carries a record layer with an information storage region. The annular retaining ring includes selectively operable means for changing the state of the disk unit to adjust the web assembly tension between the two tensions. In one embodiment, the state-changing means includes a bi-stable spring having a stable condition for each of the two web assembly tensions.

Abstract: An optical disc assembly for use with optical disc apparatus includes a flexible disc-shaped support. An annular retaining ring engages the support around its periphery. The support carries a record layer with an information storage region. Cooperating optical disc write/read apparatus has an annular, rotatable locating surface against which the support abuts. Annular spring means integral with the locating surface engage the retaining ring, applying a force to center the ring with respect to the axis of rotation of the locating surface, and to bring the support into a predetermined abutting force against the locating surface. This provides firm contact between the disc assembly support and the locating surface. The retaining ring holds the support in a first, predetermined circumferentially-symmetric storage tension. The abutting force of the support against the locating surface, induced by the spring means, may increase the tension in the support to a second, operating tension.

Abstract: An optical disc assembly includes a record layer carrying, flexible disc-shaped support with an information storage region. An annular retaining ring comprising an inner and an outer member clamps an outer peripheral portion of the support as the ring members close together. The outer peripheral portion of the support is wrapped about a radially outward facing surface of the inner ring member and a second, larger radius peripheral support portion is pushed into an annular recess in the inner ring member. Means on the retaining ring cause the portion of the support which is pushed into the recess to form a scalloped configuration within the recess. This inhibits buckling of the support. Such buckling would set up stresses in the support which would tend to be transmitted radially along the support to the information storage region.

Abstract: An optical disc-unit including (i) a flexible, disc-shaped support bearing a record layer, (ii) a flexible disc-shaped cover sheet which is transparent to write/read light and (iii) annular retaining means which engage the support and sheet, in spaced relation, substantially continuously around peripheral regions. In preferred embodiments the retaining means symmetrically tension the sheet and support into substantially flat dispositions. Cooperative optical disc write/read apparatus and optical disc-unit fabrication methods are also disclosed.

Abstract: An optical disc-unit including (i) a flexible, disc-shaped support bearing a record layer, (ii) a flexible disc-shaped cover sheet which is transparent to write/read light and (iii) annular retaining means which engage the support and sheet, in spaced relation, substantially continuously around peripheral regions. In preferred embodiments the retaining means symmetrically tension the sheet and support into substantially flat dispositions. Cooperative optical disc write/read apparatus and optical disc-unit fabrication methods are also disclosed.

Abstract: Methods and means for reducing undesirable effects of dirt particles on a flexible record device are disclosed. These undesirable effects are alleviated in accordance with the present invention by using a multilayer cushioning device to absorb the effect of dirt particles. The multilayer cushioning device comprises an amorphous cushioning layer, a flexible encompassing layer and, optionally, a flexible protective layer. The cushioning device can be superposed on the backside of the flexible record device itself, on a rigid platen of a recording or reading apparatus, or on a separate insert to be placed between the record device and the platen.

Abstract: A cartridge for enclosing a video-disc, which comprises a sleeve and a tray. The video-disc is located into a cavity hollowed in the tray and secured to the bottom of this cavity along a circular central zone through the medium of a plurality of magnetic patches glued to it and attracted by a circular magnet embedded in the bottom of the cavity.

Abstract: Stretched surface recording disk (SD) 10 comprises an annular support 12 having raised annular ridges 42 and 28 at its inside and outside diameters 22 and 30 with a base portion 24 in between the two ridges, and an annular recording medium film 14 held in radial tension and stretched across the base portion by adhering the film to attachment surfaces 48 and 36 near the inside and outside diameters respectively. The SD is annealed twice .[.duringmanufacture.]. .Iadd.during manufacture .Iaddend.to relieve stress in the stretched film 14. This annealing results in SD essentially free from track anisotropy and stress distribution anisotropy in the plane of the disk. As a result, data tracks are more stable than in previous SD, track density can be greater, and the SD is generally more reliable.

Abstract: The present invention provides a method for internally damping a rotatable storage article which is subject to resonant vibrations. More specifically, the present invention provides a method of improving the damping properties of a rotatable storage article by introducing a viscoelastic material as an inner layer(s) of the rotatable storage article. The invention also provides the damped rotatable storage articles themselves.