US20070237063A1 - Optical disc and method of protecting same - Google Patents
Optical disc and method of protecting same Download PDFInfo
- Publication number
- US20070237063A1 US20070237063A1 US11/707,267 US70726707A US2007237063A1 US 20070237063 A1 US20070237063 A1 US 20070237063A1 US 70726707 A US70726707 A US 70726707A US 2007237063 A1 US2007237063 A1 US 2007237063A1
- Authority
- US
- United States
- Prior art keywords
- optical disc
- projections
- flat surface
- digital data
- substantially flat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 190
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000001746 injection moulding Methods 0.000 claims description 6
- 238000003860 storage Methods 0.000 abstract description 7
- 239000000356 contaminant Substances 0.000 abstract description 3
- 230000007547 defect Effects 0.000 abstract description 3
- 239000010410 layer Substances 0.000 description 22
- 238000004519 manufacturing process Methods 0.000 description 8
- 239000004417 polycarbonate Substances 0.000 description 8
- 229920000515 polycarbonate Polymers 0.000 description 8
- 238000013500 data storage Methods 0.000 description 7
- 239000004033 plastic Substances 0.000 description 6
- 230000036961 partial effect Effects 0.000 description 5
- 230000008901 benefit Effects 0.000 description 3
- 239000002356 single layer Substances 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 230000000284 resting effect Effects 0.000 description 2
- 239000004923 Acrylic lacquer Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 238000010382 chemical cross-linking Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000002355 dual-layer Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000012858 resilient material Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
- 229920001169 thermoplastic Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 239000004416 thermosoftening plastic Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/24097—Structures for detection, control, recording operation or replay operation; Special shapes or structures for centering or eccentricity prevention; Arrangements for testing, inspecting or evaluating; Containers, cartridges or cassettes
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/24018—Laminated discs
- G11B7/24027—Layers; Shape, structure or physical properties thereof
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
- G11B23/0014—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture record carriers not specifically of filamentary or web form
- G11B23/0021—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture record carriers not specifically of filamentary or web form discs
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
- G11B23/0014—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture record carriers not specifically of filamentary or web form
- G11B23/0021—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture record carriers not specifically of filamentary or web form discs
- G11B23/0028—Details
- G11B23/0035—Details means incorporated in the disc, e.g. hub, to enable its guiding, loading or driving
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/24003—Shapes of record carriers other than disc shape
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
- G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
- G11B7/254—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of protective topcoat layers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/26—Apparatus or processes specially adapted for the manufacture of record carriers
Definitions
- the present invention relates to an optical disc for storage and retrieval of digital data and to a method of protecting the optical disc.
- Optical discs such as compact discs (CDs) and digital videodiscs (DVDs), have become the accepted medium for storing and retrieving large amounts of digital information (data).
- Standard CDs and DVDs have the same physical dimensions (12 cm OD, 1.2 mm thickness), but differ primarily in the amount of data that each can hold.
- a standard CD can store up to about 783 megabytes of audio programming, while DVDs can hold between about 4.38 gigabytes (single-sided/single-layer DVD) and about 15.9 gigabytes (double-sided/dual-layer DVD) of multimedia programming (photographs, video, audio, etc.).
- CD-ROMs read only memory compact discs
- CD-R recordable compact discs
- DVD-R recordable DVDs
- CD-RW rewritable compact discs
- Optical discs owe their large storage capacity to the way they represent digital data.
- digitized (binary) data are encoded on the discs as a sequence of microscopic pits separated by smooth areas (lands) that define a continuous track that spirals outward from the center of the disc.
- Adjacent tracks on CDs are 1600 nm apart, and the minimum pit length is 830 nm. DVD's achieve their greater storage capacity, in part, by shrinking the distance between adjacent tracks (740 nm) and by decreasing the minimum pit length (400-440 nm).
- Recordable compact discs and rewritable compact discs employ similar data encoding, except that the “pits” on CD-Rs and CD-RWs are replaced by “dark” spots formed, respectively, on a light-sensitive organic dye layer or light-excitable crystal layer.
- Optical disc readers retrieve data using a laser pickup assembly and a tracking system.
- the laser pickup assembly focuses a laser beam on the spinning optical disc, while the tracking system moves the laser pickup assembly outward from the center of the disc.
- the optical reader adjusts the angular speed of the disc during data retrieval so that pits and lands of a single track stream past the laser beam at constant linear velocity.
- the optical pickup includes a detector (e.g., photodiode array) which detects any light reflected by the optical disc. Laser light hitting a land reflects at a higher intensity than laser light hitting a pit (or dark spot) which scatters the light.
- the optical disc reader translates these temporal changes in detected light intensity into a stream of binary data.
- Optical discs have relatively simple, but elegant construction.
- Digital videodiscs for example, are composed of one or more layers of plastic (e.g., optical grade polycarbonate) that are individually formed by injection molding.
- One surface of each layer contains the encoded data as a spiral track of microscopic pits and lands, while another surface is substantially planar.
- DVD manufactures cover the surface containing the pits and lands with a thin metallic layer.
- the plastic layers that will become the outermost layers of the DVD are coated with semi-reflective gold, while the plastic layers that will become the innermost layers are coated with aluminum. The use of gold allows the laser pickup assembly to focus laser light through the outer layers onto the inner layers of the DVD.
- Audio CD and CD-ROMs are made in a similar manner, but comprise a single polycarbonate layer laminated to a metallic film and relatively thin acrylic layer.
- optical discs are mechanically robust and inexpensive. Despite these advantages, however, optical discs can be improved.
- the polycarbonate plastic layer has excellent optical properties and good dimensional stability, it can be scratched during handling, which may compromise data stored on the disc. For example, after removing compact discs from their protective cases, users often place them on comparatively hard flat surfaces, such as a tabletop or desktop, with the polycarbonate or readable side face down (label-side face up). Since optical discs are quite thin, users find it difficult to pickup CDs without dragging them across the tabletop. In doing so, hard contaminants on the surface of the tabletop and any defects in the tabletop surface may scratch, gouge, or scuff the polycarbonate plastic layer.
- the present invention overcomes, or at least mitigates, one or more of the problems described above.
- the present invention provides an optical disc having projections or embossments on one or both surfaces of the disc.
- the projections act as pedestals that elevate the bulk of the optical disc above the flat surface.
- the resulting gap or clearance enables users to grasp and to pick up the optical discs without dragging the discs across the flat surface.
- the clearance helps prevent damage to the optical disc caused by contaminants on the flat surface or by defects in the flat surface.
- the projections are sized to provide adequate clearance between the disc and the flat surface, while preventing or reducing interference between the projections and components of optical disc readers and drives.
- the projections may range in height up to about one mm, i.e., about the thickness of a standard compact disc (CD) or digital videodisc (DVD), but typically the height of the projections is about half (0.6 mm) or less than the thickness of a standard CD or DVD.
- the projections are ordinarily provided at predefined non-data portions of the optical disc—e.g., in the program lead-out region or between the clamping region and the program lead-in region—so that the projections will not disturb data storage or retrieval.
- the projections may be placed in a disc's data storage (program) area if it lacks encoded digital data.
- the optical disc may also include one or more depressions that are sized and configured to receive projections from another disc, which facilitates stacking of the optical discs.
- the present invention also includes a system and method for protecting an optical disc that is used to store and retrieve digital data.
- the system includes one or more projections or embossments that may be applied to a surface of the optical disc.
- the projections are sized and configured to prevent or minimize interference with digital data retrieval and to provide clearance between the surface of the optical disc and a substantially flat surface when the surface of the optical disc is placed on the substantially flat surface.
- the method includes providing one or more projections on at least one surface of the optical disc.
- the projections are sized and configured to prevent interference with digital data retrieval and to provide clearance between the optical disc and the substantially flat surface.
- the projections may be formed during fabrication of the optical disc (i.e., by injection molding) or may be applied to the surface of the optical disc by bonding techniques.
- FIG. 1 is a bottom view of an optical disc having projections or embossments for protecting the optical disc surface.
- FIG. 2 shows an enlarged partial cross section of the optical disc through section line 2 of FIG. 1 .
- FIG. 3 shows an enlarged partial cross section of the optical disc through section line 3 of FIG. 1 .
- FIG. 4 shows a side view of a stack of two optical discs resting on a flat surface such as a tabletop or desktop.
- FIG. 5 shows the placement of an optical disc having clearance projections or embossments within a section of an optical disc reader or player.
- FIG. 6 is a bottom view of an optical disc having projections or embossments that are applied following fabrication of the optical disc.
- FIG. 7 shows an enlarged partial cross section of the optical disc through section line 7 of FIG. 6 .
- FIG. 8 is a bottom view of another embodiment of an optical disc having projections or embossments that may have different physical characteristics, including shape, height, and orientation.
- FIG. 1 shows a bottom view of an optical disc 10 having first 12 and second 14 sets of projections or embossments for protecting the optical disc 10 from damage (scratches, gouges, scuff marks, etc.).
- first 12 and second 14 sets of projections or embossments for protecting the optical disc 10 from damage (scratches, gouges, scuff marks, etc.).
- CD standard audio compact disc
- DVD digital videodisc
- the disclosed invention is not limited to audio CDs and to DVDs, but applies generally to any optical disc that is used to store and retrieve digital data, including read only memory compact discs (CD-ROMs), recordable compact discs (CD-R), recordable DVDs (DVD-R), rewritable compact discs (CD-RW), high density fluorescent multilayer (FMD) ROM media, and the like.
- CD-ROMs read only memory compact discs
- CD-R recordable compact discs
- DVD-R recordable DVDs
- CD-RW rewritable compact discs
- FMD high density fluorescent multilayer
- the optical disc 10 shown in FIG. 1 is comprised of a pair of substantially parallel first 16 and second 18 surfaces. As shown in FIG. 1 , the first 16 and second 18 surfaces have substantially circular and concentric outer 20 and inner 22 peripheries, although generally the optical disc's outer periphery may assume any shape. As noted above, digitized (binary) data are encoded on the optical disc 10 as a sequence of microscopic pits (or dark spots) interrupted by smooth areas (lands) that define a continuous track (or concentric tracks) spiraling outward from the center of the disc 10 . In the embodiment shown in FIG. 1 , the encoded data lies within a data storage (program) area 24 that can be accessed by shining laser light through the substantially transparent first (bottom) surface 16 .
- data storage (program) area 24 that can be accessed by shining laser light through the substantially transparent first (bottom) surface 16 .
- the data storage area 24 is defined by a lead-in area 26 and a lead-out area 28 , which are located adjacent to the inner 22 and outer 20 peripheries of the first surface 16 , respectively.
- the lead-in and lead outer areas begin, respectively, at radii 23 mm and 58 mm, and end at radii 25 mm and 60 mm.
- the lead-in area 26 typically contains digital silence (no data) in the main channel plus the optical disc's table of contents in the subcode Q-channel; the lead-out area 28 usually contains no data.
- the first 12 and second 14 sets of projections are located in predefined non-data regions of the optical disc 10 .
- the first set of projections 12 is located on the optical disc's first surface 16 within the lead-out area 28 .
- the second set of projections 14 is located on the optical disc's first surface 16 between a clamping region 30 and the lead-in area 26 .
- the clamping region 30 generally refers to a portion of the optical disc 10 that contacts a disc drive mechanism during playback or recording (see FIG. 5 ).
- a ridge which is known as a stacking ring 32 , encircles the inner periphery 22 of the optical disc 10 and limits the outer radius of the clamping region 30 .
- the second set of projections 14 may replace the stacking ring 32 .
- Each set of projections 12 , 14 shown in FIG. 1 is comprised of four discrete and elongated projections 12 , 14 , although the number of individual projections and their distribution may vary among optical discs.
- the sets of projections 12 , 14 shown in FIG. 1 are evenly distributed within the lead-out area 28 and adjacent to the lead-in area 26 , which helps stabilize the (rotating) optical disc 10 during playback and recording.
- each set of projections 12 , 14 are offset, such that any individual second projection 14 lies about midway between rays of an angle formed by the center of the optical disc 10 and two adjacent first projections 12 . This latter arrangement should provide a more uniform clearance between the optical disc 10 and any flat surface the disc 10 is placed on.
- first set of projections 12 it is often desirable to arrange the projections so that the angular displacement between any two adjacent projections is about 2 ⁇ /n, where n is the number of projections belonging to that set.
- n is the number of projections belonging to that set.
- the optical disc 10 may include the first set of projections 12 , but no second set of projections 14 , or may include the second set of projections 14 , but no first set of projections 12 .
- the optical disc 10 may include more than two sets of projections ( FIG. 8 ).
- the optical disc may employ projections having any desirable shape, including spherical sections, spheroidal sections, ellipsoidal sections, tetrahedrons, quadrahedrons, pentahedrons, hexahedrons, etc. Besides the discrete projections 12 , 14 shown in FIG.
- the optical disc may additionally or alternatively include one or more continuous projections that circumscribe the inner periphery 22 of the optical disc, similar to the stacking ring 32 located adjacent to the clamping region 30 .
- the continuous projections are substantially larger than the stacking ring 32 , such that when the optical disc 10 is placed on a flat surface, a gap exists between the flat surface and the bottom surface 16 of the optical disc 10 .
- the projections or embossments may also be located in areas that are usually reserved for data storage.
- projections may be located within the data storage area 24 adjacent to the lead-out area 28 , as long as the particular optical disc contains no data in that area. This will often be the case when the amount of stored data is less than the optical disc's data storage capacity since CDs and single-layer DVDs encode data in a track that spirals outward from the lead-in 26 area.
- the projections may be applied or formed on both the first 16 and second 18 surfaces of the optical disc 10 . Since data is read through its first (bottom) surface 16 , the optical disc 10 shown in FIG. 1 has no projections located on its second (top) surface 18 . However, with double-sided DVDs, data can be read through substantially transparent bottom and top surfaces. Moreover, even if data is only accessed through the bottom surface, minor scratches on the top (label) surface of audio CDs, CD-ROMs, CD-Rs, and CD-RWs may compromise data integrity since the acrylic layer that protects the metallized reflective layer is much thinner than the polycarbonate layer.
- the optical disc 10 of FIG. 1 has first 34 and second 36 depressions on the second surface 18 , which are sized to accommodate the projections 12 , 14 .
- the depressions 34 , 36 are located adjacent to the projections 12 , 14 and facilitate stacking of optical discs.
- the height of the projections 12 , 14 are greater than the depth of the depressions 34 , 36 so that a gap or clearance will exist between adjacent optical discs when stacked. Note, however, that it may be desirable to size the depressions 34 , 36 so that the clearance between adjacent optical discs is a small fraction of the optical disc 10 thickness. Also note that the height of the ridge 32 shown in FIG. 3 is substantially less than the height of the projections 14 .
- FIG. 4 shows a side view of a stack 38 of two optical discs 10 resting on a flat surface 40 such as a tabletop or desktop.
- the optical discs 10 have depressions 34 , 36 such as those shown in FIG. 2 and FIG. 3 .
- the projections 12 , 14 and depressions 34 , 36 stabilize the stack 38 of optical discs 10 and minimize the relative movement of adjacent optical discs 10 that may damage their surfaces 16 , 18 .
- the height of each of the projections 12 , 14 shown in FIG. 1 does not vary significantly among projections 12 , 14 so that a gap or clearance 42 between the first surface 16 of the optical disc 10 and the flat surface 40 of the tabletop is substantially uniform.
- a gap or clearance 44 between respective first 16 and second 18 surfaces of adjacent optical discs is less than the clearance 42 between the optical disc 10 and the flat surface 40 . Nonetheless, the clearance 44 between adjacent optical discs 10 is sufficient to minimize damage to their surfaces 16 , 18 .
- the heights of individual projections 12 , 14 are comparable to the thickness of the optical disc 10 (i.e., about one mm). Generally, however, the projections are sized to provide adequate clearance between the optical disc 10 and the flat surface 40 , while minimizing interference between the projections 12 , 14 and components of optical disc readers and drives. For compact discs and videodiscs, this corresponds to projection heights less than the thickness of the optical disc, and more typically, to projection heights about half or less than the thickness of standard CDs or DVDs.
- FIG. 5 shows the placement of an optical disc 10 ′ having clearance projections or embossments within a portion of an optical disc reader 46 (player).
- the optical disc 10 ′ shown in FIG. 5 includes sets of projections 12 ′ located on both first 16 and second 18 surfaces along the outer periphery 20 of the disc 10 ′.
- the optical disc reader 46 includes an optical disc drive 48 comprised of a motor 50 for rotating the optical disc 10 ′ about an axis 52 containing its center, a platen 54 , and a cylindrical spindle 56 that is sized to accommodate the inner periphery (not shown) of the optical disc 10 ′.
- the disc drive 48 also includes spring-loaded tabs 58 that force the optical disc 10 ′ against the platen 54 at the clamping region 30 , thereby securing the optical disc 10 ′ during playback.
- the optical disc reader 46 also includes a disc cradle 60 and housing 62 , which are shown in cross-section for clarity. As can be seen in FIG. 5 , the projections 12 ′ are sized to prevent interference with the components optical disc reader 46 , including the optical disc drive 48 , the disc cradle 60 and the optical reader housing 62 .
- the projections 12 , 12 ′, 14 and depressions 34 , 36 shown in FIG. 1 - FIG. 5 may be provided in various ways.
- the projections 12 , 12 ′, 14 (and depressions 34 , 36 ) may be formed by injection molding during fabrication of the optical disc 10 , 10 ′.
- the projections 12 , 12 ′, 14 or embossments may be applied to an optical disc 10 , 10 ′ following its fabrication.
- Useful application methods include adhesive bonding, thermal welding, friction bonding, interference bonding, and the like.
- the projections 12 , 12 ′, 14 may be applied as thermosetting or thermoplastic liquid polymers that solidify through chemical cross-linking or cooling.
- the projections 12 , 12 ′, 14 may be applied as decals or similar self-adhesive stock material. When applied after fabrication of the optical disc 10 , 10 ′, the projections 12 , 12 ′, 14 may be supplied in kits that are applied by users of optical discs.
- After market suppliers may also provide the projections 12 , 12 ′, 14 by hot stamping.
- a heated tool pin, rod, etc.
- a heated tool having the requisite shape may be pressed against the second (top) surface 18 of the optical disc 10 of FIG. 1 - FIG. 3 , forming depressions 34 , 36 and corresponding projections 12 , 14 on the second 18 and first (bottom) 16 surfaces, respectively.
- FIG. 6 is a bottom view of an optical disc 10 ′′ having projections 12 ′′ or embossments that are applied following fabrication of the optical disc 10 ′′.
- the projections 12 ′′ are held in place by an interference fit or friction bonding.
- the projections 12 ′′ are located within the lead-out area 28 of the optical disc 10 ′′, but extend slightly outward from disc's outer periphery 20 .
- the projections 12 ′′ are located on both the first 16 and second 18 surfaces of optical disc 10 ′′.
- Each projection 12 ′′ is made of a resilient material and contains a slot 64 , which is slightly smaller than the thickness of the optical disc 10 ′′.
- individual projections 12 ′′ are clipped onto the outer periphery 20 of the optical disc 10 ′′ and are held in place by friction between the walls 66 of the slot 64 and the surfaces 16 , 18 of the optical disc 10 ′′.
- the sets of projections 12 , 12 ′, 12 ′′, 14 , 14 ′ shown in FIG. 1 through FIG. 7 have similar shape, height, and orientation, other embodiments may include sets of projections that have different physical characteristics.
- FIG. 8 is a bottom view of an optical disc 10 ′′′ having first 12 ′′′, second 14 ′′, and third 68 sets of projections or embossments on the first (bottom) surface 16 of the optical disc 10 ′′′.
- the first 12 ′′′ and second 14 ′′ sets of projections are evenly distributed in circular bands within the lead-out area 28 and adjacent to the lead-in area 26 , respectively.
- each set of projections 12 ′′′, 14 ′′ are offset, such that any individual second projection 14 ′′ lies about midway between rays of an angle formed by the center 70 of the optical disc 10 ′′′ and two adjacent first projections 12 ′′′.
- each of the first set of projections 12 ′′′ has a longitudinal (major) axis 72 that is substantially tangent to a first circle 74 which contains the centers of the first set of projections 12 ′′′.
- each of the second set of projections 14 ′′′ has a longitudinal axis 76 that is substantially normal to a second circle 78 which contains the centers of the second set of projections 14 ′′′.
- the optical disc 10 ′′′ includes projections having different heights and shapes.
- each of the third set of projections 68 is disposed within the lead-out area 28 of the optical disc 10 ′′′, about midway between two adjacent first projections 12 ′′′.
- each of the third set of projections 68 has the shape of a spherical section.
- their heights are substantially less than the heights of the first 12 ′′′ and second 14 ′′ sets of projections.
- first 12 ′′′ and second 14 ′′ sets of projections may have heights about equal to one half the thickness of a standard CD or DVD (e.g., 0.6 mm).
- the third set of projections 68 may have heights about equal to one quarter the thickness of a standard CD or DVD (e.g., 0.3 mm).
- the differences in orientation, shape, and height among the sets of projections 12 ′′′, 14 ′′, 68 may offer some advantages.
- the use of the smaller third set of projections 68 permits greater spacing of the first set of projections 12 ′′′ without significantly affecting the protection of the first surface 16 .
- the third set of projections 68 helps maintain a clearance between the two surfaces—albeit a smaller clearance than the first set of projections 12 ′′′ provides.
- the increased spacing of the first set of projections 12 ′′′ and the radial orientation of the second set of projections 14 ′′ help minimize interference between slot-loading optical disc readers and drives and the first 12 ′′′ and second 14 ′′ sets of projections.
- the projections 12 ′′′, 14 ′′, 68 may be provided using any of the methods described above.
- the projections 12 ′′′, 14 ′′, 68 may be formed by injection molding during fabrication of the optical disc 10 ′′′ or may be applied to the optical disc 10 ′′′ following its fabrication.
Abstract
An optical disc for storage and retrieval of digital data, and a system and method for protecting the optical disc is disclosed. The optical disc has projections or embossments on one or both surfaces. When the optical disc is placed on a substantially flat surface such as a tabletop or a desktop, the projections act as pedestals that elevate the optical disc above the flat surface. The resulting gap or clearance helps prevent damage to the optical disc caused by contaminants on the flat surface or by defects in the flat surface. The projections are sized to provide adequate clearance between the disc and the flat surface, while minimizing interference between the projections and components of optical disc readers and drives. The optical disc may also include one or more depressions that are sized and configured to receive projections from another disc, which facilitates stacking of the optical discs.
Description
- This application claims the benefit of U.S. Provisional Application No. 60/270,434, filed Feb. 21, 2001.
- 1. Field of the Invention
- The present invention relates to an optical disc for storage and retrieval of digital data and to a method of protecting the optical disc.
- 2. Discussion
- Optical discs, such as compact discs (CDs) and digital videodiscs (DVDs), have become the accepted medium for storing and retrieving large amounts of digital information (data). Standard CDs and DVDs have the same physical dimensions (12 cm OD, 1.2 mm thickness), but differ primarily in the amount of data that each can hold. A standard CD can store up to about 783 megabytes of audio programming, while DVDs can hold between about 4.38 gigabytes (single-sided/single-layer DVD) and about 15.9 gigabytes (double-sided/dual-layer DVD) of multimedia programming (photographs, video, audio, etc.). Other optical storage discs include read only memory compact discs (CD-ROMs), recordable compact discs (CD-R), recordable DVDs (DVD-R), and rewritable compact discs (CD-RW). Though physically similar to audio CDs, CD-ROMs, CD-Rs and CD-RWs can store slightly less data (i.e., less than about 700 megabytes) because a fraction of their respective storage capacities are used by a file system and data associated with enhanced error correction.
- Optical discs owe their large storage capacity to the way they represent digital data. With CDs and single-layer DVDs, digitized (binary) data are encoded on the discs as a sequence of microscopic pits separated by smooth areas (lands) that define a continuous track that spirals outward from the center of the disc. Adjacent tracks on CDs are 1600 nm apart, and the minimum pit length is 830 nm. DVD's achieve their greater storage capacity, in part, by shrinking the distance between adjacent tracks (740 nm) and by decreasing the minimum pit length (400-440 nm). Recordable compact discs and rewritable compact discs employ similar data encoding, except that the “pits” on CD-Rs and CD-RWs are replaced by “dark” spots formed, respectively, on a light-sensitive organic dye layer or light-excitable crystal layer.
- Optical disc readers (CD or DVD players, CD-ROM, CD-R or CR-RW drives, etc.) retrieve data using a laser pickup assembly and a tracking system. During playback, the laser pickup assembly focuses a laser beam on the spinning optical disc, while the tracking system moves the laser pickup assembly outward from the center of the disc. The optical reader adjusts the angular speed of the disc during data retrieval so that pits and lands of a single track stream past the laser beam at constant linear velocity. The optical pickup includes a detector (e.g., photodiode array) which detects any light reflected by the optical disc. Laser light hitting a land reflects at a higher intensity than laser light hitting a pit (or dark spot) which scatters the light. The optical disc reader translates these temporal changes in detected light intensity into a stream of binary data.
- Optical discs have relatively simple, but elegant construction. Digital videodiscs, for example, are composed of one or more layers of plastic (e.g., optical grade polycarbonate) that are individually formed by injection molding. One surface of each layer contains the encoded data as a spiral track of microscopic pits and lands, while another surface is substantially planar. Prior to assembling the layers, DVD manufactures cover the surface containing the pits and lands with a thin metallic layer. The plastic layers that will become the outermost layers of the DVD are coated with semi-reflective gold, while the plastic layers that will become the innermost layers are coated with aluminum. The use of gold allows the laser pickup assembly to focus laser light through the outer layers onto the inner layers of the DVD. Following preparation of the plastic layers, each is coated with acrylic lacquer, pressed together, and cured to form the disc. For single-sided discs, a label is applied onto the non-readable side (i.e., side opposite the polycarbonate layer or layers containing pits and lands). Audio CD and CD-ROMs are made in a similar manner, but comprise a single polycarbonate layer laminated to a metallic film and relatively thin acrylic layer.
- Compared to competing technologies such as magnetic storage media, optical discs are mechanically robust and inexpensive. Despite these advantages, however, optical discs can be improved. Although the polycarbonate plastic layer has excellent optical properties and good dimensional stability, it can be scratched during handling, which may compromise data stored on the disc. For example, after removing compact discs from their protective cases, users often place them on comparatively hard flat surfaces, such as a tabletop or desktop, with the polycarbonate or readable side face down (label-side face up). Since optical discs are quite thin, users find it difficult to pickup CDs without dragging them across the tabletop. In doing so, hard contaminants on the surface of the tabletop and any defects in the tabletop surface may scratch, gouge, or scuff the polycarbonate plastic layer. Similarly, users often stack CDs to conserve space. Any dirt particles trapped between individual CDs may also damage the surfaces of individual CDs during handling of the stack. Although the optical properties of polycarbonate and on-disc error correction help reduce the affects of surface scratches, repeated damage to CD surfaces over time may render some data unreadable.
- The present invention overcomes, or at least mitigates, one or more of the problems described above.
- The present invention provides an optical disc having projections or embossments on one or both surfaces of the disc. When the optical disc is placed on a generally flat surface such as a tabletop or a desktop, the projections act as pedestals that elevate the bulk of the optical disc above the flat surface. The resulting gap or clearance enables users to grasp and to pick up the optical discs without dragging the discs across the flat surface. Moreover, even if the optical disc is dragged across the tabletop or desktop, the clearance helps prevent damage to the optical disc caused by contaminants on the flat surface or by defects in the flat surface. The projections are sized to provide adequate clearance between the disc and the flat surface, while preventing or reducing interference between the projections and components of optical disc readers and drives. The projections may range in height up to about one mm, i.e., about the thickness of a standard compact disc (CD) or digital videodisc (DVD), but typically the height of the projections is about half (0.6 mm) or less than the thickness of a standard CD or DVD. In addition, the projections are ordinarily provided at predefined non-data portions of the optical disc—e.g., in the program lead-out region or between the clamping region and the program lead-in region—so that the projections will not disturb data storage or retrieval. Generally, however, the projections may be placed in a disc's data storage (program) area if it lacks encoded digital data. The optical disc may also include one or more depressions that are sized and configured to receive projections from another disc, which facilitates stacking of the optical discs.
- The present invention also includes a system and method for protecting an optical disc that is used to store and retrieve digital data. The system includes one or more projections or embossments that may be applied to a surface of the optical disc. The projections are sized and configured to prevent or minimize interference with digital data retrieval and to provide clearance between the surface of the optical disc and a substantially flat surface when the surface of the optical disc is placed on the substantially flat surface. Similarly, the method includes providing one or more projections on at least one surface of the optical disc. Like the inventive system, the projections are sized and configured to prevent interference with digital data retrieval and to provide clearance between the optical disc and the substantially flat surface. The projections may be formed during fabrication of the optical disc (i.e., by injection molding) or may be applied to the surface of the optical disc by bonding techniques.
-
FIG. 1 is a bottom view of an optical disc having projections or embossments for protecting the optical disc surface. -
FIG. 2 shows an enlarged partial cross section of the optical disc throughsection line 2 ofFIG. 1 . -
FIG. 3 shows an enlarged partial cross section of the optical disc throughsection line 3 ofFIG. 1 . -
FIG. 4 shows a side view of a stack of two optical discs resting on a flat surface such as a tabletop or desktop. -
FIG. 5 shows the placement of an optical disc having clearance projections or embossments within a section of an optical disc reader or player. -
FIG. 6 is a bottom view of an optical disc having projections or embossments that are applied following fabrication of the optical disc. -
FIG. 7 shows an enlarged partial cross section of the optical disc throughsection line 7 ofFIG. 6 . -
FIG. 8 is a bottom view of another embodiment of an optical disc having projections or embossments that may have different physical characteristics, including shape, height, and orientation. -
FIG. 1 shows a bottom view of anoptical disc 10 having first 12 and second 14 sets of projections or embossments for protecting theoptical disc 10 from damage (scratches, gouges, scuff marks, etc.). For clarity, we describe various embodiments of theoptical disc 10 in terms of a standard audio compact disc (CD), and to a lesser extent, in terms of a digital videodisc (DVD). However, the disclosed invention is not limited to audio CDs and to DVDs, but applies generally to any optical disc that is used to store and retrieve digital data, including read only memory compact discs (CD-ROMs), recordable compact discs (CD-R), recordable DVDs (DVD-R), rewritable compact discs (CD-RW), high density fluorescent multilayer (FMD) ROM media, and the like. - The
optical disc 10 shown inFIG. 1 is comprised of a pair of substantially parallel first 16 and second 18 surfaces. As shown inFIG. 1 , the first 16 and second 18 surfaces have substantially circular and concentric outer 20 and inner 22 peripheries, although generally the optical disc's outer periphery may assume any shape. As noted above, digitized (binary) data are encoded on theoptical disc 10 as a sequence of microscopic pits (or dark spots) interrupted by smooth areas (lands) that define a continuous track (or concentric tracks) spiraling outward from the center of thedisc 10. In the embodiment shown inFIG. 1 , the encoded data lies within a data storage (program)area 24 that can be accessed by shining laser light through the substantially transparent first (bottom)surface 16. Thedata storage area 24 is defined by a lead-inarea 26 and a lead-out area 28, which are located adjacent to the inner 22 and outer 20 peripheries of thefirst surface 16, respectively. For a standard audio CD, the lead-in and lead outer areas begin, respectively, at radii 23 mm and 58 mm, and end atradii 25 mm and 60 mm. The lead-inarea 26 typically contains digital silence (no data) in the main channel plus the optical disc's table of contents in the subcode Q-channel; the lead-out area 28 usually contains no data. - As can be seen in
FIG. 1 , the first 12 and second 14 sets of projections are located in predefined non-data regions of theoptical disc 10. Thus, the first set ofprojections 12 is located on the optical disc'sfirst surface 16 within the lead-out area 28. Similarly, the second set ofprojections 14 is located on the optical disc'sfirst surface 16 between a clampingregion 30 and the lead-inarea 26. The clampingregion 30 generally refers to a portion of theoptical disc 10 that contacts a disc drive mechanism during playback or recording (seeFIG. 5 ). In standard CDs and DVDs, a ridge, which is known as a stackingring 32, encircles theinner periphery 22 of theoptical disc 10 and limits the outer radius of the clampingregion 30. In some embodiments, the second set ofprojections 14 may replace the stackingring 32. - Each set of
projections FIG. 1 is comprised of four discrete andelongated projections projections FIG. 1 are evenly distributed within the lead-out area 28 and adjacent to the lead-inarea 26, which helps stabilize the (rotating)optical disc 10 during playback and recording. Furthermore, each set ofprojections second projection 14 lies about midway between rays of an angle formed by the center of theoptical disc 10 and two adjacentfirst projections 12. This latter arrangement should provide a more uniform clearance between theoptical disc 10 and any flat surface thedisc 10 is placed on. Thus, for a given set of projections (e.g. first set of projections 12), it is often desirable to arrange the projections so that the angular displacement between any two adjacent projections is about 2π/n, where n is the number of projections belonging to that set. In addition, it is generally desirable to offset the first 12 and second 14 projections so that the angular displacement between adjacent first 12 and second 14 projections is π/n radians. In this way the projections' center of mass lies near the optical disc's rotation center (i.e., within its inner periphery). - In other embodiments, the
optical disc 10 may include the first set ofprojections 12, but no second set ofprojections 14, or may include the second set ofprojections 14, but no first set ofprojections 12. In addition, theoptical disc 10 may include more than two sets of projections (FIG. 8 ). The optical disc may employ projections having any desirable shape, including spherical sections, spheroidal sections, ellipsoidal sections, tetrahedrons, quadrahedrons, pentahedrons, hexahedrons, etc. Besides thediscrete projections FIG. 1 , the optical disc may additionally or alternatively include one or more continuous projections that circumscribe theinner periphery 22 of the optical disc, similar to the stackingring 32 located adjacent to the clampingregion 30. However, the continuous projections are substantially larger than the stackingring 32, such that when theoptical disc 10 is placed on a flat surface, a gap exists between the flat surface and thebottom surface 16 of theoptical disc 10. - Although it is usually desirable to locate projections within the predefined non-data areas, the projections or embossments may also be located in areas that are usually reserved for data storage. For example, projections may be located within the
data storage area 24 adjacent to the lead-out area 28, as long as the particular optical disc contains no data in that area. This will often be the case when the amount of stored data is less than the optical disc's data storage capacity since CDs and single-layer DVDs encode data in a track that spirals outward from the lead-in 26 area. - In general, the projections may be applied or formed on both the first 16 and second 18 surfaces of the
optical disc 10. Since data is read through its first (bottom)surface 16, theoptical disc 10 shown inFIG. 1 has no projections located on its second (top)surface 18. However, with double-sided DVDs, data can be read through substantially transparent bottom and top surfaces. Moreover, even if data is only accessed through the bottom surface, minor scratches on the top (label) surface of audio CDs, CD-ROMs, CD-Rs, and CD-RWs may compromise data integrity since the acrylic layer that protects the metallized reflective layer is much thinner than the polycarbonate layer. - The
optical disc 10 ofFIG. 1 has first 34 and second 36 depressions on thesecond surface 18, which are sized to accommodate theprojections FIG. 2 andFIG. 3 , which show enlarged partial cross sections of theoptical disc 10 throughsection line 2 andsection line 3, respectively, thedepressions projections projections depressions depressions optical disc 10 thickness. Also note that the height of theridge 32 shown inFIG. 3 is substantially less than the height of theprojections 14. -
FIG. 4 shows a side view of astack 38 of twooptical discs 10 resting on aflat surface 40 such as a tabletop or desktop. Although not shown inFIG. 4 , theoptical discs 10 havedepressions FIG. 2 andFIG. 3 . Theprojections depressions stack 38 ofoptical discs 10 and minimize the relative movement of adjacentoptical discs 10 that may damage theirsurfaces projections FIG. 1 does not vary significantly amongprojections clearance 42 between thefirst surface 16 of theoptical disc 10 and theflat surface 40 of the tabletop is substantially uniform. Since thedepressions projections clearance 44 between respective first 16 and second 18 surfaces of adjacent optical discs is less than theclearance 42 between theoptical disc 10 and theflat surface 40. Nonetheless, theclearance 44 between adjacentoptical discs 10 is sufficient to minimize damage to theirsurfaces - In the embodiment shown in
FIG. 4 , the heights ofindividual projections optical disc 10 and theflat surface 40, while minimizing interference between theprojections -
FIG. 5 shows the placement of anoptical disc 10′ having clearance projections or embossments within a portion of an optical disc reader 46 (player). Theoptical disc 10′ shown inFIG. 5 includes sets ofprojections 12′ located on both first 16 and second 18 surfaces along theouter periphery 20 of thedisc 10′. Theoptical disc reader 46 includes anoptical disc drive 48 comprised of amotor 50 for rotating theoptical disc 10′ about anaxis 52 containing its center, aplaten 54, and acylindrical spindle 56 that is sized to accommodate the inner periphery (not shown) of theoptical disc 10′. Thedisc drive 48 also includes spring-loadedtabs 58 that force theoptical disc 10′ against theplaten 54 at the clampingregion 30, thereby securing theoptical disc 10′ during playback. Theoptical disc reader 46 also includes adisc cradle 60 andhousing 62, which are shown in cross-section for clarity. As can be seen inFIG. 5 , theprojections 12′ are sized to prevent interference with the componentsoptical disc reader 46, including theoptical disc drive 48, thedisc cradle 60 and theoptical reader housing 62. - The
projections depressions FIG. 1 -FIG. 5 may be provided in various ways. For example, theprojections depressions 34, 36) may be formed by injection molding during fabrication of theoptical disc projections optical disc projections projections optical disc projections - After market suppliers may also provide the
projections surface 18 of theoptical disc 10 ofFIG. 1 -FIG. 3 , formingdepressions corresponding projections -
FIG. 6 is a bottom view of anoptical disc 10″ havingprojections 12″ or embossments that are applied following fabrication of theoptical disc 10″. Theprojections 12″ are held in place by an interference fit or friction bonding. Like theprojections 12′ shown inFIG. 1 , theprojections 12″ are located within the lead-out area 28 of theoptical disc 10″, but extend slightly outward from disc'souter periphery 20. - As shown in
FIG. 7 , which is an enlarged partial cross section throughsection line 7 inFIG. 6 , theprojections 12″ are located on both the first 16 and second 18 surfaces ofoptical disc 10″. Eachprojection 12″ is made of a resilient material and contains aslot 64, which is slightly smaller than the thickness of theoptical disc 10″. To install,individual projections 12″ are clipped onto theouter periphery 20 of theoptical disc 10″ and are held in place by friction between thewalls 66 of theslot 64 and thesurfaces optical disc 10″. - Although on a given
optical disc projections FIG. 1 throughFIG. 7 have similar shape, height, and orientation, other embodiments may include sets of projections that have different physical characteristics. - For example,
FIG. 8 is a bottom view of anoptical disc 10′″ having first 12′″, second 14″, and third 68 sets of projections or embossments on the first (bottom) surface 16 of theoptical disc 10′″. Like the sets ofprojections FIG. 1 , the first 12′″ and second 14″ sets of projections are evenly distributed in circular bands within the lead-out area 28 and adjacent to the lead-inarea 26, respectively. Additionally, each set ofprojections 12′″, 14″ are offset, such that any individualsecond projection 14″ lies about midway between rays of an angle formed by the center 70 of theoptical disc 10′″ and two adjacentfirst projections 12′″. Though both sets ofprojections 12′″, 14″ are shaped like a section of an ellipsoid, their orientations are different. As can be seen inFIG. 8 , each of the first set ofprojections 12′″ has a longitudinal (major)axis 72 that is substantially tangent to afirst circle 74 which contains the centers of the first set ofprojections 12′″. In contrast, each of the second set ofprojections 14′″ has alongitudinal axis 76 that is substantially normal to asecond circle 78 which contains the centers of the second set ofprojections 14′″. - Besides different orientation, the
optical disc 10′″ includes projections having different heights and shapes. For example, each of the third set ofprojections 68 is disposed within the lead-out area 28 of theoptical disc 10′″, about midway between two adjacentfirst projections 12′″. Unlike the ellipsoidal first 12′″ and second 14″ sets of projections, each of the third set ofprojections 68 has the shape of a spherical section. Moreover, though the third set ofprojections 68 have similar sizes, their heights are substantially less than the heights of the first 12′″ and second 14″ sets of projections. For example, the first 12′″ and second 14″ sets of projections may have heights about equal to one half the thickness of a standard CD or DVD (e.g., 0.6 mm). In contrast, the third set ofprojections 68 may have heights about equal to one quarter the thickness of a standard CD or DVD (e.g., 0.3 mm). - The differences in orientation, shape, and height among the sets of
projections 12′″, 14″, 68 may offer some advantages. For instance, the use of the smaller third set ofprojections 68 permits greater spacing of the first set ofprojections 12′″ without significantly affecting the protection of thefirst surface 16. When placed on a substantially flat surface with the optical disc's 10′″first surface 16 facing the flat surface, the third set ofprojections 68 helps maintain a clearance between the two surfaces—albeit a smaller clearance than the first set ofprojections 12′″ provides. The increased spacing of the first set ofprojections 12′″ and the radial orientation of the second set ofprojections 14″, help minimize interference between slot-loading optical disc readers and drives and the first 12′″ and second 14″ sets of projections. Theprojections 12′″, 14″, 68 may be provided using any of the methods described above. For example, theprojections 12′″, 14″, 68 may be formed by injection molding during fabrication of theoptical disc 10′″ or may be applied to theoptical disc 10′″ following its fabrication. - It should be understood that the above description is intended to be illustrative and not limiting. Many embodiments will be apparent to those of skill in the art upon reading the above description. Therefore, the scope of the invention should be determined, not with reference to the above description, but instead with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all patents, articles and references, including patent applications and publications, if any, are incorporated herein by reference in their entirety and for all purposes.
Claims (20)
1. An optical disc that is used to store and retrieve digital data, the optical disc comprising:
first and second surfaces having inner and outer peripheries, at least the first surface of the optical disc capable of transmitting light;
an area for storing digital data, the area located between the inner and outer peripheries of the first and second surfaces, the digital data being accessible by shining light through the first surface of the optical disc; and
one or more projections located on at least the first surface of the optical disc, the one or more projections sized and configured to minimize interference with retrieving the digital data stored on the optical disc and to provide a clearance between the first surface of the optical disc and a substantially flat surface when the optical disc is placed on the substantially flat surface with the first surface of the optical disc facing the substantially flat surface.
2. The optical disc of claim 1 , wherein the one or more projections are located on the first surface of the optical disc between the area for storing digital data and the outer periphery of the optical disc.
3. The optical disc of claim 1 , wherein the one or more projections are located on the first surface of the optical disc between the area for storing digital data and the inner periphery of the optical disc.
4. The optical disc of claim 1 , wherein the one or more projections are located on the first surface of the optical disc between the area for storing digital data and the inner and outer peripheries of the optical disc.
5. The optical disc of claim 1 , wherein the one or more projections are located in the area for storing digital data adjacent to the outer periphery of the optical disc.
6. The optical disc of claim 1 , wherein the one or more projections are located in predefined non-data areas.
7. The optical disc of claim 1 , wherein the one or more projections have heights about less than the optical disc thickness.
8. The optical disc of claim 1 , wherein the one or more projections have heights about equal to or less than one half the optical disc thickness.
9. The optical disc of claim 1 , wherein the one or more projections are continuous and circumscribe the inner periphery of the optical disc.
10. The optical disc of claim 1 , further comprising depressions located on the second surface of the optical disc.
11. The optical disc of claim 10 , wherein the depressions are sized and configured to accommodate the one or more projections.
12. The optical disc of claim 1 , further comprising one or more projections located on the second surface of the optical disc, the one or more projections sized and configured to minimize interference with digital data retrieval and to provide clearance between the second surface of the optical disc and a substantially flat surface when the optical disc is placed on the substantially flat surface with the second surface of the optical disc facing the substantially flat surface.
13. A system for protecting an optical disc that is used to store and retrieve digital data, the system comprising one or more projections for applying to a surface of an optical disc, the one or more projections sized and configured to minimize interference with digital data retrieval and to provide a clearance between the surface of the optical disc and a substantially flat surface when the optical disc is placed on the substantially flat surface with the surface of the optical disc facing the substantially flat surface.
14. The system of claim 13 , wherein the one or more projections are continuous and circumscribes an interior periphery of the optical disc.
15. A method of protecting an optical disc used to store and retrieve digital data, the method comprising:
providing one or more projections on at least a first surface of an optical disc, the one or more projections sized and configured to prevent interference with digital data retrieval and to provide a clearance between the first surface of the optical disc and a substantially flat surface when the optical disc is placed on the substantially flat surface with the first surface of the optical disc facing the substantially flat surface.
16. The method of claim 15 , further comprising forming the projections on the first surface of the optical disc by injection molding.
17. The method of claim 15 , further comprising applying the projections on the first surface of the optical disc by bonding.
18. The method of claim 15 , further comprising forming the projections on the first surface of the optical disc by hot stamping.
19. The method of claim 15 , further comprising providing the projections on a second surface of the optical disc.
20. The method of claim 15 , further comprising forming depressions in a second surface of the optical disc by injection molding.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/707,267 US20070237063A1 (en) | 2001-02-21 | 2007-02-16 | Optical disc and method of protecting same |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US27043401P | 2001-02-21 | 2001-02-21 | |
US09/964,711 US6680898B2 (en) | 2001-02-21 | 2001-09-27 | Optical disc and method of protecting same |
US10/717,636 US7212489B2 (en) | 2001-02-21 | 2003-11-21 | Optical disc and method of protecting same |
US11/707,267 US20070237063A1 (en) | 2001-02-21 | 2007-02-16 | Optical disc and method of protecting same |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/717,636 Continuation US7212489B2 (en) | 2001-02-21 | 2003-11-21 | Optical disc and method of protecting same |
Publications (1)
Publication Number | Publication Date |
---|---|
US20070237063A1 true US20070237063A1 (en) | 2007-10-11 |
Family
ID=26954300
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/964,711 Expired - Fee Related US6680898B2 (en) | 2001-02-21 | 2001-09-27 | Optical disc and method of protecting same |
US10/717,636 Expired - Fee Related US7212489B2 (en) | 2001-02-21 | 2003-11-21 | Optical disc and method of protecting same |
US11/707,267 Abandoned US20070237063A1 (en) | 2001-02-21 | 2007-02-16 | Optical disc and method of protecting same |
Family Applications Before (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/964,711 Expired - Fee Related US6680898B2 (en) | 2001-02-21 | 2001-09-27 | Optical disc and method of protecting same |
US10/717,636 Expired - Fee Related US7212489B2 (en) | 2001-02-21 | 2003-11-21 | Optical disc and method of protecting same |
Country Status (10)
Country | Link |
---|---|
US (3) | US6680898B2 (en) |
EP (1) | EP1377972A2 (en) |
JP (1) | JP2004538590A (en) |
KR (1) | KR100578169B1 (en) |
CN (1) | CN1256726C (en) |
AU (1) | AU2002245466B2 (en) |
CA (1) | CA2438940A1 (en) |
HK (1) | HK1066627A1 (en) |
MX (1) | MXPA03007581A (en) |
WO (1) | WO2002069335A2 (en) |
Families Citing this family (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4215923B2 (en) * | 2000-02-02 | 2009-01-28 | 株式会社ソニー・ディスクアンドデジタルソリューションズ | Optical disc and mold for injection compression molding thereof |
JP4043175B2 (en) * | 2000-06-09 | 2008-02-06 | Tdk株式会社 | Optical information medium and manufacturing method thereof |
US6680898B2 (en) * | 2001-02-21 | 2004-01-20 | Todd J. Kuchman | Optical disc and method of protecting same |
US6842409B2 (en) * | 2001-02-21 | 2005-01-11 | Scratch-Less Disc Industries, Llc | Optical disc and method of protecting same |
US6667953B2 (en) | 2001-12-21 | 2003-12-23 | Seth Matson | Optical disk protector and method of use |
US6901600B2 (en) * | 2002-01-03 | 2005-05-31 | Julian Liu | Protective cover for a data storage disc and method of use |
TW572327U (en) * | 2002-05-22 | 2004-01-11 | Daxon Technology Inc | An anti-adherent disc |
TW581314U (en) * | 2002-05-27 | 2004-03-21 | Daxon Technology Inc | An anti-abrasion disc |
JP3961466B2 (en) * | 2002-09-05 | 2007-08-22 | 松下電器産業株式会社 | Optical information recording medium, method for manufacturing the same, and method for holding optical information recording medium |
KR100499479B1 (en) * | 2002-09-10 | 2005-07-05 | 엘지전자 주식회사 | Digital Versatile Disc of high density |
US20040081070A1 (en) * | 2002-10-23 | 2004-04-29 | Correa Jose Alfonso | CD& DVD medium outter protector ring |
ES2261032B1 (en) * | 2004-09-16 | 2007-11-16 | Universidade Da Coruña | COMPACT DISK WITH PROTECTIVE OUTLETS OF READING FACE. |
WO2006089176A2 (en) * | 2005-02-14 | 2006-08-24 | Garcia Anthony J | System and method for surface protection of optical-based digital storage media |
US20060184958A1 (en) * | 2005-02-14 | 2006-08-17 | Garcia J A | System and method for surface protection of optical-based digital storage media |
DE102005052241A1 (en) * | 2005-11-02 | 2007-05-03 | Saia-Burgess Oldenburg Gmbh & Co. Kg | Welding equipment tool for joining two or more plastic components uses LED arrangement to heat components |
JP2008004252A (en) | 2006-05-26 | 2008-01-10 | Tdk Corp | Information medium substrate and information medium |
US7785689B2 (en) * | 2006-08-21 | 2010-08-31 | Imation Corp. | Raw material conserving optical data storage media |
US8561093B2 (en) * | 2009-02-26 | 2013-10-15 | Imation Corp. | Stacking techniques for thin optical data storage media |
US20100235851A1 (en) * | 2009-03-11 | 2010-09-16 | Global Publishing Inc. | Flexible Optical Disc with Outer Edge Ring |
TWM388717U (en) * | 2010-04-09 | 2010-09-11 | Ritek Corp | Optical disc |
US8462607B1 (en) | 2010-04-09 | 2013-06-11 | Ritek Corporation | Optical disc with a discontinuous surface structure |
JP4904421B2 (en) * | 2010-08-16 | 2012-03-28 | シバテック株式会社 | Disc type recording medium |
Citations (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2631859A (en) * | 1949-07-30 | 1953-03-17 | Allan R Ellsworth | Phonograph record |
US3787274A (en) * | 1970-05-25 | 1974-01-22 | Victor Company Of Japan | Phonograph record disc |
US3931457A (en) * | 1972-09-04 | 1976-01-06 | U.S. Philips Corporation | Information carrier having addressed information tracks |
US3931459A (en) * | 1974-02-04 | 1976-01-06 | Zenith Radio Corporation | Video disc |
US4038524A (en) * | 1974-06-21 | 1977-07-26 | Thomson-Brandt | Data carrier optically readable by transmission and method of manufacturing such a data carrier |
US4074282A (en) * | 1976-05-13 | 1978-02-14 | North American Philips Corporation | Radiation-sensitive record with protected sensitive surface |
US4111698A (en) * | 1975-07-30 | 1978-09-05 | Fuji Photo Film Co., Ltd. | Spin-coated photosensitive silver halide photomask |
US4113492A (en) * | 1976-04-08 | 1978-09-12 | Fuji Photo Film Co., Ltd. | Spin coating process |
US4175145A (en) * | 1975-04-28 | 1979-11-20 | Teletype Corporation | Making memory structure for laser recording system |
US4204686A (en) * | 1978-02-06 | 1980-05-27 | Church Walter E | Phonograph record protective cushion |
US4326282A (en) * | 1980-01-09 | 1982-04-20 | U.S. Philips Corporation | Apparatus for reproducing digitally coded information recorded on an optically readable disc-shaped record carrier |
US4336545A (en) * | 1980-12-18 | 1982-06-22 | Eastman Kodak Company | Optical disc structure, method and apparatus physically optimized for writing and reading with a single wavelength |
US4353767A (en) * | 1979-08-20 | 1982-10-12 | Discovision Associates | Method of manufacturing an optical reading disc |
US4371954A (en) * | 1980-02-01 | 1983-02-01 | Thomson-Csf | Reversible memory structure with thermo-optical writing and optical reading and process for writing and erasing said structure |
US4462036A (en) * | 1982-10-14 | 1984-07-24 | Eastman Kodak Company | Optical disc assemblies for optical disc write/read apparatus |
US4519064A (en) * | 1980-10-27 | 1985-05-21 | Nippon Columbia Kabushikikaisha | Optical record disc |
US4536869A (en) * | 1983-01-17 | 1985-08-20 | Eastman Kodak Company | Optical disk assembly |
US4546464A (en) * | 1982-02-05 | 1985-10-08 | Matsushita Electric Industrial Co., Ltd. | Method of manufacturing an optical recording/reproducing disc |
US4633458A (en) * | 1983-06-20 | 1986-12-30 | Polygram Gmbh | Disc-shaped, optically-readable information carrier having a protective edge and/or center part |
US4719137A (en) * | 1984-04-13 | 1988-01-12 | Sharp Kabushiki Kaisha | Magneto-optic memory element |
US4737408A (en) * | 1985-08-21 | 1988-04-12 | Tdk Corporation | Magneto-optical recording medium having plasma-polymerized protective layers |
US4808456A (en) * | 1986-10-17 | 1989-02-28 | Fuji Photo Film Co., Ltd. | Magneto-optical recording medium and method of making the same |
US4811326A (en) * | 1985-02-11 | 1989-03-07 | Gerber Arthur M | Method of recording digital information on an array of equally spaced micromirrors |
US4891798A (en) * | 1984-07-25 | 1990-01-02 | Sony Corporation | Optical disc player with focus control for preventing erroneous focus on outer surface of optical disc |
US4961077A (en) * | 1988-02-19 | 1990-10-02 | E. I. Du Pont De Nemours And Company | Method for affixing information on read-only optical discs |
US5128922A (en) * | 1987-09-29 | 1992-07-07 | Sharp Kabushiki Kaisha | Optical disk with glass substrate and method of producing same |
US5247495A (en) * | 1990-02-21 | 1993-09-21 | Matsushita Electric Industrial Co., Ltd. | Optical magnetic disk with separate regions provided on it |
US5513169A (en) * | 1993-10-06 | 1996-04-30 | Sony Corporation | CD-ROM with machine-readable i.d. code |
US5987003A (en) * | 1996-07-23 | 1999-11-16 | Mitsubishi Chemical Corporation | Coated disk substrate having a small thickness region |
US6424488B1 (en) * | 1999-02-22 | 2002-07-23 | Seagate Technology Llc | Peripherally extending disc ring to limit disc deflection and to provide disc stack balancing |
US7212489B2 (en) * | 2001-02-21 | 2007-05-01 | Scratch-Less Disc Industries, Llc | Optical disc and method of protecting same |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB473988A (en) | 1936-04-24 | 1937-10-25 | Franz Neumann | Improvements relating to the production of sound records |
NL7710162A (en) | 1977-09-16 | 1979-03-20 | Philips Nv | METHOD FOR MANUFACTURING AN OPTICALLY READABLE INFORMATION DISK USING A FLAT, STIFFENING HEAT CONDUCTIVE PLATE OF INORGANIC MATERIAL |
DE2839359A1 (en) | 1978-09-09 | 1980-03-27 | Licentia Gmbh | Diode coding matrix for one-out-of-n code - forms binary code using two sets of switches and reduced number of diodes |
DE3127993A1 (en) | 1981-07-15 | 1983-02-10 | Polygram Gmbh, 2000 Hamburg | DISK-SHAPED OPTICALLY READABLE INFORMATION CARRIER WITH HIGH STORAGE DENSITY |
JPS5848089A (en) | 1981-09-18 | 1983-03-19 | 日本原子力事業株式会社 | Driving training simulator |
JPH09320111A (en) | 1996-05-31 | 1997-12-12 | Ricoh Co Ltd | Optical disk |
JP2001023238A (en) | 1999-07-02 | 2001-01-26 | Hitachi Maxell Ltd | Information recording medium |
-
2001
- 2001-09-27 US US09/964,711 patent/US6680898B2/en not_active Expired - Fee Related
-
2002
- 2002-02-19 JP JP2002568370A patent/JP2004538590A/en active Pending
- 2002-02-19 KR KR1020037010993A patent/KR100578169B1/en not_active IP Right Cessation
- 2002-02-19 EP EP02713626A patent/EP1377972A2/en not_active Withdrawn
- 2002-02-19 AU AU2002245466A patent/AU2002245466B2/en not_active Ceased
- 2002-02-19 WO PCT/US2002/004805 patent/WO2002069335A2/en not_active Application Discontinuation
- 2002-02-19 CN CNB02808411XA patent/CN1256726C/en not_active Expired - Fee Related
- 2002-02-19 MX MXPA03007581A patent/MXPA03007581A/en active IP Right Grant
- 2002-02-19 CA CA002438940A patent/CA2438940A1/en not_active Abandoned
-
2003
- 2003-11-21 US US10/717,636 patent/US7212489B2/en not_active Expired - Fee Related
-
2004
- 2004-12-01 HK HK04109528A patent/HK1066627A1/en not_active IP Right Cessation
-
2007
- 2007-02-16 US US11/707,267 patent/US20070237063A1/en not_active Abandoned
Patent Citations (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2631859A (en) * | 1949-07-30 | 1953-03-17 | Allan R Ellsworth | Phonograph record |
US3787274A (en) * | 1970-05-25 | 1974-01-22 | Victor Company Of Japan | Phonograph record disc |
US3931457A (en) * | 1972-09-04 | 1976-01-06 | U.S. Philips Corporation | Information carrier having addressed information tracks |
US3931459A (en) * | 1974-02-04 | 1976-01-06 | Zenith Radio Corporation | Video disc |
US4038524A (en) * | 1974-06-21 | 1977-07-26 | Thomson-Brandt | Data carrier optically readable by transmission and method of manufacturing such a data carrier |
US4175145A (en) * | 1975-04-28 | 1979-11-20 | Teletype Corporation | Making memory structure for laser recording system |
US4111698A (en) * | 1975-07-30 | 1978-09-05 | Fuji Photo Film Co., Ltd. | Spin-coated photosensitive silver halide photomask |
US4113492A (en) * | 1976-04-08 | 1978-09-12 | Fuji Photo Film Co., Ltd. | Spin coating process |
US4074282A (en) * | 1976-05-13 | 1978-02-14 | North American Philips Corporation | Radiation-sensitive record with protected sensitive surface |
US4204686A (en) * | 1978-02-06 | 1980-05-27 | Church Walter E | Phonograph record protective cushion |
US4353767A (en) * | 1979-08-20 | 1982-10-12 | Discovision Associates | Method of manufacturing an optical reading disc |
US4326282A (en) * | 1980-01-09 | 1982-04-20 | U.S. Philips Corporation | Apparatus for reproducing digitally coded information recorded on an optically readable disc-shaped record carrier |
US4371954A (en) * | 1980-02-01 | 1983-02-01 | Thomson-Csf | Reversible memory structure with thermo-optical writing and optical reading and process for writing and erasing said structure |
US4519064A (en) * | 1980-10-27 | 1985-05-21 | Nippon Columbia Kabushikikaisha | Optical record disc |
US4336545A (en) * | 1980-12-18 | 1982-06-22 | Eastman Kodak Company | Optical disc structure, method and apparatus physically optimized for writing and reading with a single wavelength |
US4546464A (en) * | 1982-02-05 | 1985-10-08 | Matsushita Electric Industrial Co., Ltd. | Method of manufacturing an optical recording/reproducing disc |
US4462036A (en) * | 1982-10-14 | 1984-07-24 | Eastman Kodak Company | Optical disc assemblies for optical disc write/read apparatus |
US4536869A (en) * | 1983-01-17 | 1985-08-20 | Eastman Kodak Company | Optical disk assembly |
US4633458A (en) * | 1983-06-20 | 1986-12-30 | Polygram Gmbh | Disc-shaped, optically-readable information carrier having a protective edge and/or center part |
US4719137A (en) * | 1984-04-13 | 1988-01-12 | Sharp Kabushiki Kaisha | Magneto-optic memory element |
US4891798A (en) * | 1984-07-25 | 1990-01-02 | Sony Corporation | Optical disc player with focus control for preventing erroneous focus on outer surface of optical disc |
US4811326A (en) * | 1985-02-11 | 1989-03-07 | Gerber Arthur M | Method of recording digital information on an array of equally spaced micromirrors |
US4737408A (en) * | 1985-08-21 | 1988-04-12 | Tdk Corporation | Magneto-optical recording medium having plasma-polymerized protective layers |
US4808456A (en) * | 1986-10-17 | 1989-02-28 | Fuji Photo Film Co., Ltd. | Magneto-optical recording medium and method of making the same |
US5128922A (en) * | 1987-09-29 | 1992-07-07 | Sharp Kabushiki Kaisha | Optical disk with glass substrate and method of producing same |
US4961077A (en) * | 1988-02-19 | 1990-10-02 | E. I. Du Pont De Nemours And Company | Method for affixing information on read-only optical discs |
US5247495A (en) * | 1990-02-21 | 1993-09-21 | Matsushita Electric Industrial Co., Ltd. | Optical magnetic disk with separate regions provided on it |
US5513169A (en) * | 1993-10-06 | 1996-04-30 | Sony Corporation | CD-ROM with machine-readable i.d. code |
US5987003A (en) * | 1996-07-23 | 1999-11-16 | Mitsubishi Chemical Corporation | Coated disk substrate having a small thickness region |
US6424488B1 (en) * | 1999-02-22 | 2002-07-23 | Seagate Technology Llc | Peripherally extending disc ring to limit disc deflection and to provide disc stack balancing |
US7212489B2 (en) * | 2001-02-21 | 2007-05-01 | Scratch-Less Disc Industries, Llc | Optical disc and method of protecting same |
Also Published As
Publication number | Publication date |
---|---|
US7212489B2 (en) | 2007-05-01 |
US20020114264A1 (en) | 2002-08-22 |
KR100578169B1 (en) | 2006-05-12 |
MXPA03007581A (en) | 2004-10-15 |
CN1256726C (en) | 2006-05-17 |
AU2002245466B2 (en) | 2005-12-22 |
HK1066627A1 (en) | 2005-03-24 |
CA2438940A1 (en) | 2002-09-06 |
US20040103424A1 (en) | 2004-05-27 |
JP2004538590A (en) | 2004-12-24 |
US6680898B2 (en) | 2004-01-20 |
WO2002069335A3 (en) | 2002-12-12 |
CN1503969A (en) | 2004-06-09 |
EP1377972A2 (en) | 2004-01-07 |
WO2002069335A2 (en) | 2002-09-06 |
KR20030095392A (en) | 2003-12-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20070237063A1 (en) | Optical disc and method of protecting same | |
AU2002245466A1 (en) | Optical disc and method of protecting same | |
US7417941B2 (en) | Optical disc and method of protecting same | |
KR100499479B1 (en) | Digital Versatile Disc of high density | |
US9105284B2 (en) | Magnetic media having graphene wear protection layers | |
US8663771B2 (en) | Optical media having graphene wear protection layers | |
US6711118B1 (en) | Optical information recording medium for recording optically reproducible signals thereon through the use of a recording laser beam and method for recording optical information thereon | |
US20030156531A1 (en) | Disk data storage media with edge track data surface, methods to manufacture, exploit and convert conventional disk media to that having an edge track data surface | |
JP2003059115A (en) | Recording medium | |
CN1722264A (en) | Optical disc | |
US20030174639A1 (en) | Thin-type optical disc | |
KR20050059005A (en) | Digital versatile disc of high density | |
JP2004006008A (en) | Optical information recording medium and its recording and reproducing device | |
WO2005045818A1 (en) | Optical information recording medium, optical information recording medium recording/reproducing method, and recording/reproducing apparatus | |
CN1512495A (en) | Anti-wear and scratch optical disc | |
CN1512494A (en) | Anti-wear and scratch optical disc | |
JPH10222881A (en) | Optical disk sticking device | |
JPS63104236A (en) | Card-shaped optical recording medium |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SCRATCH-LESS DISC INDUSTRIES, LLC, COLORADO Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KUCHMAN, TODD J.;REEL/FRAME:019460/0171 Effective date: 20031215 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |