Classifications

• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/04—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the shape
  • G06K19/041—Constructional details
  • G06K19/042—Constructional details the record carrier having a form factor of a credit card and including a small sized disc, e.g. a CD or DVD
  • G06K19/044—Constructional details the record carrier having a form factor of a credit card and including a small sized disc, e.g. a CD or DVD comprising galvanic contacts for contacting an integrated circuit chip thereon
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/08—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code using markings of different kinds or more than one marking of the same kind in the same record carrier, e.g. one marking being sensed by optical and the other by magnetic means
  • G06K19/10—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code using markings of different kinds or more than one marking of the same kind in the same record carrier, e.g. one marking being sensed by optical and the other by magnetic means at least one kind of marking being used for authentication, e.g. of credit or identity cards
  • G06K19/14—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code using markings of different kinds or more than one marking of the same kind in the same record carrier, e.g. one marking being sensed by optical and the other by magnetic means at least one kind of marking being used for authentication, e.g. of credit or identity cards the marking being sensed by radiation
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
  • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
  • G06K7/14—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation using light without selection of wavelength, e.g. sensing reflected white light
• • 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
  • G11B7/002—Recording, reproducing or erasing systems characterised by the shape or form of the carrier
  • G11B7/0033—Recording, reproducing or erasing systems characterised by the shape or form of the carrier with cards or other card-like flat carriers, e.g. flat sheets of optical film
• • 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
  • G11B7/002—Recording, reproducing or erasing systems characterised by the shape or form of the carrier
  • G11B7/0037—Recording, reproducing or erasing systems characterised by the shape or form of the carrier with discs
• • 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 invention relates to a data registration medium in the form of a rectangular card, preferably for optical data storage.
• a generally used data storage medium has the form of a plastic card with the standardised format 53.975 x 85.598 mm.
• Data storage on cards of this kind known up to now has taken place with the aid of data-carrying strips, usually parallel to the longitudinal direction of the card.
• These strips may be of magnetic material, as with the generally prevailing charge, credit and bank cards. They may also comprise an optically active layer where data is stored in the form of portions which are either reflecting or non-reflecting. Reading is performed by a linear relative movement in the longitudinal direction of the card between it and a magnetic or optical reading head.
• CD Compact Disk
• the data carrier in this system is a disk where the signal is stored in the form of a spiral track comprising a series of depressions on the surface of the disc. The bottom of the depressions as well as intermediate surfaces are covered with a reflecting material. Reading is performed by a laser beam which is reflected by the surface of the disk and by the bottoms of the depressions. The laser beam follows the track with the aid of a simple servo mechanism which can shift the beam a minor distance radially. Moving the beam from the start of the track to its end takes place with the aid of a mechanism similar to the tone arm on an ordinary record player.
• the storage medium used in the CD system is usually programmed with digitally recorded music, and the most usual technique for producing CD records is injection moulding transparent plastics in a mould where one defining surface contains the information as a surface relief. During the moulding process this is impressed on the disk surface, which is subsequently given a thin metallic coating. Reading is done through the transparent disk. Due to the interference phenomenon the reflected light will have different intensities depending on from what part of the relief it comes.
• holes can be burnt into the storage medium with the aid of focussed light from the laser, which is then driven at high power. A lesser light power not affecting the storage medium is used for reading the information.
• the disks used for optical storage of sound (the CD disks) and video signals and as data carriers are not accepted as an easily portable data medium. Furthermore, they are intended for very large amount of data, and the reading and writing equipment must be provided with mechanical means for radially scanning the disk. It has been found that for most purposes it is satisfactory with an information quantity of ⁇ 2 Mbytes.
• a preferably rectangular card provided with an area intended for optical registration of data in the form of markings modifying the properties of the reflected light from a light beam incident on the area.
• the invention is distinguished by this area being formed as a annular ring, width of which is much less than its diameter.
• Figures 1 and 2 each illustrate an embodiment of a data carrier
• Figure 3 is a cross section through a known carrier
• Figure 4 schematically illustrates a reading and/or writing means.
• the data carrier illustrated in Figure 1 consists of a plastic card, suitably of the ISO standard format of approximately 54 x 86 mm.
• a narrow annular information-carrying area 2 This area accommodates such as a spiral groove for example of the kind described in the above-mentioned article in "Philips Technical Review", but is intended for writing.
• the groove is schematically illustrated in Figure 3 in sectioned perspective, and comprises a transparent base material 5 that has been provided with a relief pattern with impressions 6.
• the entire relief pattern is covered by a thin layer 7 in which information may be stored witht the aid of a sufficiently powerful laser beam, which is incident on the layer 7 through the transparent layer.
• the laser lig t is incident on the layer 7 there is a change in the optical properties of this layer, e.g. by a hole being burnt into it. Reading is performed with the sam laser but then at a power which is so low that the properties of the layer ar not affected. The reflected light is detected and gives rise to a signal varyin as the state of the surface and representing the stored information. A junctio between an illuminated and non-illuminated surface during writing, and vice versa, can be interpreted as a binary One while unchanged surface condition denotes Zero.
• the groove suitably has the dimension standard for digital CD records, namely a
• a hole 3 is disposed at the centre of the annular area 2.
• This hole of a diameter as 15 mm fits the rotating spindle of a drive means taking the information groove past a fixed read and/or write station, as illustrated in Figure 4.
• the groove 2 and hole 3 have their centres at the centre of gravity of the card. It is of course possible to place the groove displaced from this position, as is illustrated in Figure 2.
• the card is not provided with any centering hole and is intended to coact with a rotating drive means equiped with a holder retaining the card such that the centre of the annular portion .2 coincides with the centre of rotation.
• FIG. 4 It is schematically illustrated in Figure 4 how a data carrier in accordance with the invention coacts with a reading and writing unit.
• the card 1 is placed on a spindle 10 fitting the hole 3 in the card.
• the spindle is driven by a motor 11 controlled by a processor unit 12.
• the light for writing and reading is generated by a laser 13 with associated optics, and passes a semitransparent mirror 14, or alternatively a polarisation prisma, and further an objective unit 15, which refracts the pencil of rays to a light spot somewhat greater than the width of the depressions.
• the objective unit contains means for adjusting the focus and also shifting the light beam transverse the grooves. Such means are known per se, and are described, e.g. in the "Philips Technical Review" article mentioned above.
• the adjusting means of the objective unit are controlled by the servo unit 21 for focussing and by the unit 22 for adjusting the beam radially as well as tracking the groove from start to finish.
• the light reflected from the card surface is guided by the mirror 14 to a detector unit 16, where the light beam is conventionally caused to be incident on a plurality of photosensors, the output signals of which, after certain processing, give three signals.
• the first is a digital signal 18 representing the stored information.
• the second is a voltage signal 19 for keeping the beam o track in the groove and which controls the position servo 22.
• the third is focussing signal used to adjust the laser beam focus so that the light spot i always positioned on the card surface, irrespective of any warping, and i controls the focussing servo 21.
• the position signal is fed to the processor 12, which after further signa processing controls the drive motor 11 and also feeds a data signal to the outpu 23.
• the fu ⁇ tion of the reading and writing unit may be controlled from an inpu 24 on the processor 12.
• a writing signal is fed to the input 24. Eac time an information bit is to be burnt the power of the laser 13 is increased The latter has low power between the information bits and is then utilised fo tracking the groove. During the reading process the laser is operated at lo power the whole time.
• the invention is not restricted to the described embodiments, and may b varied in a large number of ways within the scope of the inventive concept. Th data registration does not need to take place in the way exemplified in Figur 3. In most applications it is indeed desirable that the card may be supplied wit data during use, but in certain cases it may be supplied with permanen information, e.g. in the way used in the production of CD records.
• a storage medium of this kind may be manufacture empty of information or already partly programmed. To obtain easy trackin such media are provided with fixed grooves in an extra layer or directly in th substrate as described above. Over this the storage medium is deposited as thin layer. Writing is done as described above with the aid of a laser, which ma be the same as is used for reading but driven at a substantially increased powe so that the desired changes arise in the layer. It is also possible to provide a data registration medium in accordance with the invention with an area of a material which may be written on or erased optically. Examples of this are reversible phase conversions and magnetoptic storage.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Theoretical Computer Science (AREA)
• Health & Medical Sciences (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Computer Hardware Design (AREA)
• Electromagnetism (AREA)
• General Health & Medical Sciences (AREA)
• Toxicology (AREA)
• Artificial Intelligence (AREA)
• Computer Vision & Pattern Recognition (AREA)
• Optical Record Carriers And Manufacture Thereof (AREA)
• Optical Recording Or Reproduction (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20359556

Family Applications (1)

Country Status (4)

Cited By (17)

Citations (3)

Family Cites Families (1)

• 1985
  • 1985-03-19 SE SE8501342A patent/SE447313B/sv not_active IP Right Cessation
• 1986
  • 1986-03-19 JP JP61501930A patent/JPS62502298A/ja active Pending
  • 1986-03-19 WO PCT/SE1986/000119 patent/WO1986005620A1/en unknown
  • 1986-03-19 EP EP86902079A patent/EP0215895A1/en not_active Withdrawn

Patent Citations (3)

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