WO2004017316A1 - Disque optique a specification d'epaisseur hybride comprenant une face dvd et une face cd, et procede pour produire une face a densite double - Google Patents

Disque optique a specification d'epaisseur hybride comprenant une face dvd et une face cd, et procede pour produire une face a densite double Download PDF

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Publication number
WO2004017316A1
WO2004017316A1 PCT/AU2003/001026 AU0301026W WO2004017316A1 WO 2004017316 A1 WO2004017316 A1 WO 2004017316A1 AU 0301026 W AU0301026 W AU 0301026W WO 2004017316 A1 WO2004017316 A1 WO 2004017316A1
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WO
WIPO (PCT)
Prior art keywords
dvd
disc
hybrid
optical disc
manufacturing
Prior art date
Application number
PCT/AU2003/001026
Other languages
English (en)
Inventor
Joseph Francis Hayes
Original Assignee
Mahomy, Frances, Anne
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from AU2002950808A external-priority patent/AU2002950808A0/en
Priority claimed from AU2002952291A external-priority patent/AU2002952291A0/en
Application filed by Mahomy, Frances, Anne filed Critical Mahomy, Frances, Anne
Priority to AU2003249783A priority Critical patent/AU2003249783A1/en
Publication of WO2004017316A1 publication Critical patent/WO2004017316A1/fr

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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
    • G11B7/2403—Layers; Shape, structure or physical properties thereof
    • G11B7/24035—Recording layers
    • G11B7/24038—Multiple laminated recording 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

Definitions

  • the present invention relates generally to CD and DVD optical media, and more particularly to hybrid CD/DVD optical disc and a method of manufacture a double density DVD side in a hybrid CD/DVD disc.
  • CD Audio optical disc specifically the CD Audio format has lapsed into public domain after the natural term of its patent life and sales in the product class of CD Audio optical disc are peaking indicating the onset of a new optical disc format, mainly DVD Audio.
  • CD Audio optical disc are 1.2mm wide and are allowed to be 1.1mm to 1.5mm in width under the specification known as the red book.
  • DVD optical disc Sales of this format are just starting.
  • the DVD optical disc is 0.6mm wide but is laminated to either a second layer of DVD information (DVD9, DVD10 and DVD18) or to a blank 0.6mm wide sub straight so that the overall thickness of the disc is 1.2mm.
  • DVD sides are allowed to be typically 0.52mm to 0.68mm in width under the terms of the specification called the blue book.
  • the hybrid optical disc having CD Audio on one side and DVD information on the other side is useful as it allows for the combination of old art with current art so that there is a cross compatible product that will play on a CD player or a DVD player.
  • This is most useful for the music industry as it needs a hybrid optical disc in the short term so that it can safely transfer from the CD Audio 16bit 44.1kHz sampling specification format to the new DVD Audio 24 bit 96kHz style sampling rate.
  • a release can contain both formats on a CD/DVD hybrid optical disc and therefore not alienate the market that does not have the new DVD Audio players. They allow the record companies to reduce cost involved in releasing one product in two formats as individually autonomous optical discs.
  • the CD/DVD caracole market has designed their mechanical tolerances to the CD Audio specification.
  • these multi disc transport and/or clamping mechanisms as often found in car stackers and 5 caracole disc players and the like can handle optical disc that are between 1.1mm and 1.5mm wide.
  • the 1.62mm hybrid optical disc is incompatible with car stackers and multi disc caracole players and the like and therefore difficult to market.
  • Provisional Patent Application no. 2002950808 lodged in describes a super thin hybrid CD/DVD disc, which substantially overcomes problems of the WO 98/38637 patent application.
  • the super thin hybrid CD/DVD disc is limited in capacity on the DVD side to 4.7 Giga Bytes as the DVD side is a DVD5 technology.
  • This disc Provisional Patent Application no. 2002950808 lodged in Australia ) as a DVD5Hybrid.
  • DVD9 which uses a special manufacturing method to achieve a double density DVD side with a capacity of 9 Giga Bytes, as is well known in the art. Therefore, the market for the original DVD5Hybrid is limited to lower bit rate movies or DVD Audio content where the capacity of the DVD side is greater than 4.7 Giga Bytes.
  • DVD9Hybrid There is genuine market interest in making hybrid disc that have a 9 Giga Byte capacity DVD combined with a CD. We refer to this disc as a DVD9Hybrid.
  • the present system and method provides means for producing hybrid optical disc consisting of a CD on one side and a DVD on the other side such that the total hybrid optical disc are within the width specification as set by the red and blue book standard.
  • a further system and method provides a way to manufacture a DVD9Hybrid using in part the prior art manufacturing technique of the DVD18 process, as is well known in the art.
  • the prior art method of manufacturing DVD18 has very low yield with typically a 40% reject rate.
  • the cost of the disc can be around four times that of a DVD9 disc due simply to failure rates.
  • the further system and method to produce a DVD9Hybrid disc is performed without using the full DVD18 manufacturing process and thus with yield improvement of as little as 5% reject rate or similar rates as are experience in manufacturing DVD5 and DVD9.
  • the present invention may be utilized in various industries such as the music industry, the DVD Video movie industry, and other industries that use either CD or DVD optical disc as a format.
  • industries such as the music industry, the DVD Video movie industry, and other industries that use either CD or DVD optical disc as a format.
  • Other advantages, features, and embodiments of the present invention will be apparent from the drawings and detailed description as set forth below.
  • FIG. 1 is a block diagram of a prior art CD Audio optical disc system as defined by the red book standard.
  • FIG. 2 is a block diagram of a prior art DVD optical disc system as defined by the blue book standard.
  • FIG. 3 is a block diagram of a prior art hybrid CD/DVD optical disc system as defined by patent application WO 98/38637.
  • FIG. 4 is a block diagram of a hybrid CD/DVD optical disc system that is between 1.1mm and 1.5mm in width that uses the DVD layer as a shim so that the CD side data layer is presented closer to the read laser focusing optics and vise versa.
  • FIG. 5 is a block diagram of a hybrid CD/DVD optical disc that is 1.48mm in width and uses a lower refractive index sub straight material than normal to compensate for the reduced width so that the read laser will further function within its design principles.
  • FIG. 6 is a block diagram of an CD optical disc that is made of a plurality of laminated sub straights with at least one sub straight having a different refractive index to the others.
  • FIG. 7 is a block diagram of a Prior Art I s ' step process in making a DVD18 disc.
  • FIG. 8 is a block diagram of a Prior Art 2 nd step process in making a DVD18 disc.
  • FIG. 9 is a block diagram of a Prior Art 3 rd step process in making avDVD18 disc.
  • FIG. 10 is a block diagram of a 1 st step process in making a
  • FIG. 11 is a block diagram of a 2 nd step process in making a
  • FIG. 12 is a block diagram of a 3 rd step process in making a
  • FIG. 1 is a block diagram of a prior art CD Audio optical disc as defined by the red book standard.
  • the optical disc sub straight 100 also contains a pitted surface 101 that is sputtered with target material as is well known in the art.
  • a protective lacquer 102 is applied by spin coating to protect pitted surface 101 and the coating of sputtered target material.
  • the overall width 113 of the optical disc is typically 1.2mm but can be anywhere between 1.1mm a d 1.5mm.
  • Laser 109 sends light through a moving platform 110 containing a lens 103 such that it can be focused at the source in such a way to cause a diameter 104 of typically 0.8mm of light at an angle of incidence to the surface 117 of the optical disc sub straight 100 of typically 27 degrees 107 from the normal.
  • a 0.8mm diameter of light 104 on the surface 117 of a 1.2 mm optical grade polycarbonate sub straight 100, when incident at 27 degrees 107 from the normal shall cause an angle of refraction of typically 17 degrees 108 for the light within the sub straight 100.
  • a 0.8mm diameter circle 104 of light on the surface 117 of the sub straight 100 shall focus into typically 16-micron wide diameter of light 105 at the pitted surface 101.
  • the typically 16-micron diameter of light 105 is exactly right for tracking and reading the track of spiral data off the layer of information on the pitted surface 101 as is well known in the art.
  • the target material typically aluminum, reflects the laser light and depending on the pit depth will cause interference or reinforcement of the incoming laser light.
  • the reflected laser light follows the same optical path as the incoming light with the reversed angles of incidence and refraction.
  • the angles of incidence and refraction of light as it passes between two materials is controlled by the relationship of the refractive indexes of the two materials.
  • the refractive index for a material is controlled by the speed of light in that material compared to the speed of light in a vacuum (3 x lO ⁇ s" 1 ).
  • the speed of light is substantially the same as the speed of light in a vacuum.
  • the speed of light in optical grade polycarbonate is 1.99 x 10 8 ms- ⁇ .
  • the CD optical disc sits on a transport and/or clamping mechanism 111.
  • This transport and/or clamping mechanism 111 presents the optical disc outer surface 117 at a distance from the laser lens 103 that is within design expectations and tolerance to allow the movement 110 of the laser lens 103 to correctly focus the light onto the surface 117 of the disc to achieve the correct focus radius 105 on the pitted surface 101.
  • the distance the outer surface 117 of the optical disc is presented from the laser lens 103 is the distance 112 from the transport and/or clamping mechanism 111 to the laser 109 minus the width 113 of the optical disc.
  • CD players are designed to be in spec such that they expect the surface 117 of the disc to be somewhere between 1.1mm to 1.5mm above the transport and/or clamping mechanism 111 as these are the allowable widths for CD optical disc under the red book.
  • FIG. 2 is a block diagram of a prior art DVD optical disc as defined by the blue book standard.
  • the surface of the disc is presented the same relative distance principles from the laser lens 209 as a CD audio because the DVD disc is 1.2mm wide 213 even thought its data layer 201 is 0.6mm 214 below its outer surface 200.
  • the laser 209 is of a higher frequency, therefore a shorter wavelength, and the focus radius 206 of the laser on the disc surface 200 is smaller and the radius formed by the laser light on the pitted surface 205 is smaller.
  • FIG. 3 is a block diagram of a prior art hybrid CD/DVD optical disc as defined by patent application WO 98/38637.
  • the total width 304 of the disc is 1.62mm.
  • this has problems in that it presents the surface of the CD side 301 or the DVD side 306 0.12mm above the expected design point specified by the red and blue book standards for the distance between the transport and/or clamping mechanism 311 and the laser 309. It is also 0.12mm wider that the distance specified for the maximum width of an optical disc under the red book and blue book standards and therefore will not load in most automatic stacker as found in car audio and in 5 disc caracole players and the like. Therefore the versatility and therefore market acceptance of this prior art 1.62mm hybrid optical disc is limited.
  • FIG. 4 is a block diagram of a hybrid CD/DVD optical disc that is between 1.1mm an 1.5mm in width 403 that uses the DVD side 401 as a spacing shim so that the CD side surface 411 is presented within the specified expected design distance to the read laser 409 as specified for an optical disc manufactured under the red book specification (greater than 1.1mm and less than 1.5mm).
  • the CD side 401 acts as a spacing shim so that the DVD side surface 410 is presented with in the specified design distance to the read laser as specified for an optical disc manufactured under the blue book specification for an optical disc (1.1mm to 1.5mm).
  • the CD side width 404 has been decreased to 0.95mm (equivalent to 13.6% less than the minimum width of 1.1mm allowed for a non hybrid CD optical disc under the red book specification).
  • the CD side 402 has essentially twice the sensitivity to absolute distance variations, as does the DVD side 401.
  • the optical distance to travel within the refractive material is 1.2mm in a normal CD and 0.6mm in a normal DVD.
  • the DVD side is far more sensitive to absolute width variations as the wavelength and therefore absolute tolerances are tighter.
  • the DVD side is chosen to have the minimum under the blue book standard that is typically 0.52mm.
  • the CD side is reduced to 79% of 1.2mm so that it is 0.95mm wide and gives an overall thickness 403 to the hybrid disc of 1.48mm. As the CD side data sub straight 407 is presented closer to the laser 409 the reduced thickness still lays within the effective focus range of most CD players.
  • the pitch of the internal laser light will be stepper and it will therefore focus on a surface that is closer.
  • Variable material layers may be used to achieve piecewise linear layered curving on the laser beam light within different refractive index materials to achieve thinner optical disc sides.
  • Figure 6 shows a CD optical disc side that uses plurality of laminated layers of different refractive material Nl 602, N2 603, and N3 604.
  • the laser light 605 refracts at the juncture 607 of N air 601 and Nl 602. At the juncture of these layers a refraction angle effect will transpire as described previously.
  • the laser light 605 then again refracts at the juncture 608 of Nl 602 and N2603 and again refracts at the juncture 609 of N2 603 and N3 604.
  • the laser light 605 can be piece wise linear manipulated to shorten the path taken by the laser light within the sub straights and therefore reduce the overall thickness of the side 606.
  • the same technique may be used on the DVD side.
  • a protective coating that may have a different refractive index than the side upon which it is applied may add an additional layer to a side and achieve some contribution to width reduction of that side.
  • Gradient variable refractive index materials may be used such that the refractive index is a gradient within the sub straight material thus achieving continuous curvature of the laser beam within the refractive material thus achieving a thinner CD or DVD side.
  • a further system and method overcomes or substantially alleviates present limitations associated with the present system hybrid CD/DVD disc capacity on the DVD side. It improves production yield in the manufacture of such disc than if they where produced using conventional DVD18 technology manufacturing techniques.
  • D VD9Hybrid disc can be achieved by using conventional
  • DVD18 manufacturing methods by simply bonding one half of a DVD18 disc to a CD disc.
  • the DVD18 manufacturing process has only typically 60% yield and thus the cost of this process would mean the resultant disc would have to be doubled in price to cover the cost of rejects. Therefore an alternative economic manufacturing method is required.
  • Figure 7 shows the 1 st step process in manufacturing a prior art DVD18 disc.
  • the bonded layer 706 is made to be typically 70 microns wide thus fulfilling the requirement for DVD9 optical disc second layer distance.
  • the DVD pits 705 are of mechanical dimensions of typically 60 microns high by 60 microns wide and are between typically 180 microns to 720 microns long.
  • the DVD pits 705 of the reverse mastered DVD sub straight 703 have land where there are normally pits and vice versa, as is well known in the art.
  • Figure 8 shows the 2 nd step process in manufacturing a prior art DVD18 disc.
  • a high-pressure air jet 800 is applied to the side of the disc produced in the 1 st step described above (figure 7).
  • the mechanical property of Plexiglas is that is adheres more poorly to fully reflective target material than does polycarbonate the high pressure air jet 800 cause the Plexiglas sub straight 703 to laminate from the rest of the structure made in the 1 st step process.
  • a polycarbonate sub straight 700 with its semi transparent target material 702, the 70 micron bonding layer 706 and the fully reflective target material 704 all remain as one composite and form a half of a DVD18 disc.
  • Figure 8 shows the 3 rd step process in manufacturing a prior art DVD18 disc.
  • the half of a DVD18 901 produced in the 2 nd step manufacturing process described above (figure 8) is bonded 903 to another half of a DVD18 902 produced using the same 2 nd step manufacturing process.
  • the result is a double-sided disc that presents effectively two DVD9 sides to the optical reader 904 and 905 depending which side of the disc is facing the optics.
  • the benefit of such a disc is that its capacity is 18 Giga Bytes.
  • the problem with such a disc is that it is expensive to produce as when the air jet 800 (figure 8) is applied it often damages DVD pits 705 (figure 7) or causes lamination in part or in full to one of the other layer joints such as the junction of polycarbonate sub straight 700 to its semi reflective target material 702, or between the semi reflective target material 702 to the bonded layer 706, or the bonded layer 706 to fully reflective target material 704.
  • the main reason this lamination or damage occurs is that the only difference between the different layers is the bonding strength of the target materials to polycarbonate and Plexiglas.
  • Both layers 700 and 703 have DVD pits 705 which are identical in size and therefore structural strength.
  • the definition of where the disc should laminate is somewhat subtly defined by the poorer bonding strength of the target material to Plexiglas.
  • FIG. 10 shows the 1 st step process in the further system and method for a manufacturing process claimed in this patent.
  • a CD sub straight 1000 being either the conventional thickness described by the red book standard, or a super thin CD described with a fully reflective target material 1001 applied is bonded to a Plexiglas normal DVD sub straight 1003 which has its fully reflective target material 1004 applied. They are bonded 1002 together at any width that suits the final product (not optically sensitive).
  • the CD sub straight 1000 has CD pits 1005 which are typically 120 microns high and 120 microns wide and typically 360 microns to 1234 microns long.
  • DVD sub straight 1003 has DVD pits 1006 that are of mechanical dimensions of typically 60 microns high by 60 microns wide and typically between 180 microns to 720 microns long.
  • Figure 11 shows the 2 nd step process in the further system and method for a manufacturing process claimed in this patent.
  • a high pressure air jet 1100 is applied to the side of the disc to cause the Plexiglas sub straight 1003 to laminate from the rest of the structure produced in the 1 st step manufacturing process (figure 10).
  • the lamination is well defined at the junction of the DVD target material 1004 to the DVD plexiglass sub straight 1003 as the mechanical dimension of the CD pits 1005 are much larger than the mechanical dimensions of the DVD pits 1006.
  • the mechanical strength of the CD sub straight 1000 with its large CD pits 1005 and fully reflective target material 1001 bonded 1002 to the fully reflective target material 1004 with smaller DVD pits 1006 is a very strong structure. Therefore incorrect de- lamination is minimised and yields are far higher than in the prior art 'half of a DVD18' manufacturing process.
  • Figure 12 shows the 3 rd step process in the further system and method for a manufacturing process claimed in this patent.
  • the hybrid CD/DVD sub structure 1200 produced in the 2 nd step process (figure 10) in the further system and method for a manufacturing process claimed in this patent is bonded 1202 to a pre sputtered polycarbonate normal DVD sub straight 1201 with its semi reflective target material 1205 already applied.
  • the bonding process is controlled such that the resultant bonding layer 1202 is typically 70 microns wide as required by the DVD9 optical reading system.
  • This system is a high yield process so when combined with the hybrid CD/DVD sub structure 1200 produced in the 2 nd step process in the further system and method for a manufacturing process claimed in this patent a high yield disc is produced.
  • All DVD sub straights used to produce the hybrid CD/DVD sub structure 1200 produced in the 2 nd step process in the further system and method for a manufacturing process claimed in this patent are normal, and therefore DVD5 style mastering and stampers can be used eliminating the need for manufacturing with reversed DVD glass masters, stampers and sub straights.

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Abstract

La présente invention concerne un système et un procédé pour produire un disque optique hybride CD/DVD conçu pour avoir une épaisseur globale comprise entre 1,1 mm et 1,5 mm de sorte qu'il s'adapte à la fois aux spécifications d'épaisseur d'empileurs de disques optiques et à celles des chargeurs de disques caracole. La présente invention a également pour objet un autre système et un autre procédé relatifs à la manière dont l'indice de réfraction doit être modifié sur les matériaux substrats pour compenser le non respect de l'épaisseur de spécification des faces des CD ou des DVD de sorte qu'ils peuvent fonctionner conformément à la spécification sur un lecteur laser si nécessaire. L'invention concerne aussi un autre système et un autre procédé pour produire un disque hybride CD/DVD, la face DVD ayant une densité qui est le double de celle d'un DVD5 normal. Le disque ainsi obtenu est un disque hybride DVD9 qui peut être utilisé avec tout contenu de DVD9 normal, un CD faisant également partie du disque optique. Le procédé permet également d'obtenir un rendement très supérieur à celui obtenu par les techniques conventionnelles de production de DVD18, lorsqu'il est appliqué à la réalisation d'un disque de ce type, ce qui a pour conséquence des frais de production significativement inférieurs.
PCT/AU2003/001026 2002-08-14 2003-08-14 Disque optique a specification d'epaisseur hybride comprenant une face dvd et une face cd, et procede pour produire une face a densite double WO2004017316A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003249783A AU2003249783A1 (en) 2002-08-14 2003-08-14 Hybrid in width spec optical disc utilising a dvd and a cd side and a method for manufacturing a double density side

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
AU2002950808A AU2002950808A0 (en) 2002-08-14 2002-08-14 Hybrid in spec optical disc utilising a dvd and a cd layer
AU2002950808 2002-08-14
AU2002952291 2002-10-28
AU2002952291A AU2002952291A0 (en) 2002-10-28 2002-10-28 Method of manufacturing a double density dvd side in a dvd/cd hybrid disc

Publications (1)

Publication Number Publication Date
WO2004017316A1 true WO2004017316A1 (fr) 2004-02-26

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004008446A2 (fr) * 2002-07-11 2004-01-22 Glud & Marstrand A/S Support optique compense

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998038637A1 (fr) * 1997-02-28 1998-09-03 Wea Manufacturing, Inc. Disque hybride dvd-cd a deux faces
EP0899723A2 (fr) * 1997-08-30 1999-03-03 Samsung Electronics Co., Ltd. Disque hybride et méthode pour sa discrimination
JPH11120617A (ja) * 1997-10-17 1999-04-30 Sony Corp 光記録媒体
EP1006513A2 (fr) * 1998-12-01 2000-06-07 Dieter Dierks Support d' informations digitales optique et multicouche
WO2001011617A1 (fr) * 1999-08-05 2001-02-15 Tocano A/S Produit combine de disque numerique polyvalent/disque compact
GB2380595A (en) * 2001-10-02 2003-04-09 Flipperdisc Ltd A double sided optically readable disk
DE10150025A1 (de) * 2001-10-11 2003-04-17 Dieter Dierks Scheibenförmiger optischer Datenträger mit sowohl einer CD-als auch einer DVD-Informationsschicht

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998038637A1 (fr) * 1997-02-28 1998-09-03 Wea Manufacturing, Inc. Disque hybride dvd-cd a deux faces
EP0899723A2 (fr) * 1997-08-30 1999-03-03 Samsung Electronics Co., Ltd. Disque hybride et méthode pour sa discrimination
JPH11120617A (ja) * 1997-10-17 1999-04-30 Sony Corp 光記録媒体
EP1006513A2 (fr) * 1998-12-01 2000-06-07 Dieter Dierks Support d' informations digitales optique et multicouche
WO2001011617A1 (fr) * 1999-08-05 2001-02-15 Tocano A/S Produit combine de disque numerique polyvalent/disque compact
GB2380595A (en) * 2001-10-02 2003-04-09 Flipperdisc Ltd A double sided optically readable disk
DE10150025A1 (de) * 2001-10-11 2003-04-17 Dieter Dierks Scheibenförmiger optischer Datenträger mit sowohl einer CD-als auch einer DVD-Informationsschicht

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Derwent World Patents Index; Class T03, AN 1999-332442 *
DATABASE WPI Derwent World Patents Index; Class T03, AN 2000-444097 *
DATABASE WPI Derwent World Patents Index; Class T03, AN 2003-422656 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004008446A2 (fr) * 2002-07-11 2004-01-22 Glud & Marstrand A/S Support optique compense
WO2004008446A3 (fr) * 2002-07-11 2004-06-24 Glud & Marstrand As Support optique compense

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