Source: http://www.google.com/patents/US7095697?ie=ISO-8859-1&dq=7,177,838
Timestamp: 2015-05-03 11:43:15
Document Index: 687887881

Matched Legal Cases: ['application No. 96915172', 'application No. 95', 'Application No. 11', 'application No. 95', 'application No. 11', 'application No. 11', 'application No. 11']

Patent US7095697 - Optical disk, an optical disk barcode forming method, an optical disk ... - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsDisclosed is an optical disk barcode forming method wherein, as information to be barcoded, position information for piracy prevention, which is a form of ID, is coded as a barcode and is recorded by laser trimming on a reflective film in a PCA area of an optical disk. When playing back the thus manufactured...http://www.google.com/patents/US7095697?utm_source=gb-gplus-sharePatent US7095697 - Optical disk, an optical disk barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical diskAdvanced Patent SearchPublication numberUS7095697 B2Publication typeGrantApplication numberUS 10/783,441Publication dateAug 22, 2006Filing dateFeb 20, 2004Priority dateOct 9, 1995Fee statusPaidAlso published asCN1154097C, CN1173942A, CN1200406C, CN1324592C, CN1379394A, CN1545088A, CN1547202A, CN100342443C, DE69610859D1, DE69610859T2, DE69610860D1, DE69610860T2, DE69610861D1, DE69610861T2, DE69611906D1, DE69611906T2, DE69614580D1, DE69614580T2, DE69615418D1, DE69615418T2, DE69617478D1, DE69617478T2, DE69618633D1, DE69618633T2, DE69624390D1, DE69624390T2, DE69626329D1, DE69626329T2, DE69631914D1, DE69631914T2, DE69633031D1, DE69633031T2, DE69633353D1, DE69633353T2, DE69637606D1, EP0807929A1, EP0807929A4, EP0807929B1, EP1003162A1, EP1003162B1, EP1005033A1, EP1005033B1, EP1005034A1, EP1005034B1, EP1005035A1, EP1005035B1, EP1006516A1, EP1006516B1, EP1006517A1, EP1006517B1, EP1028422A1, EP1028422B1, EP1028423A1, EP1028423B1, EP1030297A1, EP1030297B1, EP1031974A1, EP1031974B1, EP1251501A1, EP1251501B1, EP1251502A1, EP1251502B1, EP1465164A2, EP1465164A3, EP1465164B1, EP1659580A2, EP1659580A3, EP1659580B1, US6052465, US6122373, US6125181, US6128388, US6141419, US6160888, US6175629, US6208736, US6229896, US6278671, US6285762, US6285763, US6285764, US6298138, US6449366, US6457128, US6470452, US6480960, US6552969, US6600706, US6618347, US6728882, US6757391, US6862685, US7103781, US7110544, US7520001, US8014236, US8472291, US20020070282, US20020080961, US20020089920, US20020097871, US20030172286, US20040184394, US20060131407, US20090168619, US20110286315, WO1997014146A1Publication number10783441, 783441, US 7095697 B2, US 7095697B2, US-B2-7095697, US7095697 B2, US7095697B2InventorsYoshiho Gotoh, Mitsuaki Oshima, Shinichi Tanaka, Kenji Koishi, Mitsuro MoriyaOriginal AssigneeMatsushita Electric Industrial Co., Ltd.Export CitationBiBTeX, EndNote, RefManPatent Citations (64), Non-Patent Citations (8), Referenced by (2), Classifications (167), Legal Events (3) External Links: USPTO, USPTO Assignment, EspacenetOptical disk, an optical disk barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical disk
US 7095697 B2Abstract
1. Reproduction circuit in an optical disk reproduction apparatus for use with a disk on which data is recorded, wherein in a prescribed region of said disk, an identifier is provided for indicating whether a barcode-like mark is present or not on said optical disk, said identifier and said barcode-like mark are in respectively different locations on said disk, said barcode-like mark disposed in a circumferential direction, and said barcode-like mark having a plurality of bars, each of said bars extending in a radial direction, said prescribed region is included in a control data area in which physical feature information regarding said optical disk is recorded,
said reproduction circuit comprising:
input means receiving reproduced signals from said optical disk,
demodulation means demodulating said barcode-like mark from said received reproduced signals by using reverse conversion of phase encoding method,
identifier detection means detecting whether said identifier is 0 or 1 in the received reproduced signals, and
output means outputting the value of said identifier to controlling means of said optical disk reproduction apparatus.
2. A reproduction circuit according to claim 1, wherein
a signal is generated which indicates whether or not said identifier indicates presence of said mark.
3. A reproduction circuit according to claim 1, wherein
said physical feature information includes physical characteristics of said disk.
This application is a Continuation application of U.S. patent application Ser. No. 10/081,944, filed Feb. 20, 2002, now U.S. Pat. No. 6,757,391 which is a Divisional application of U.S. patent application Ser. No. 09/713,183, filed Nov. 15, 2000, now abandoned which is a Continuation application of U.S. patent application Ser. No. 09/441,281, filed Nov. 16, 1999, which is now U.S. Pat. No. 6,285,763, issued Sep. 4, 2001, which is a Continuation of U.S. patent application Ser. No. 08/649,411, filed May 16, 1996, which is now U.S. Pat. No. 6,052,465 issued on Apr. 18, 2000.
In the manufacturing process of, optical disks, it has been commonly practiced to record a serial number, lot number, etc. on each optical disk in the form of a barcode.
A further aspect of the invention is an optical disk, wherein said barcode contains data including, in addition to said ID information, a public key of a public key encryption function corresponding to said ID information, said public key is used when encrypt prescribed data, and the encrypted prescribed data is transmitted to an external party in order to obtain from said external party a password required to reproduce said optical disk.
Yet 13th another aspect of the invention is an optical disk barcode forming method, wherein said optical disk is constructed from two disk-substrates laminated together.
Still another aspect of the invention is a reproduction apparatus wherein:
FIG. 13( a) is a diagram showing a physical arrangement of addresses on a legitimate CD according to the embodiment, and (b) is a physical arrangement of addresses on an illegally duplicated CD according to the embodiment;
FIG. 14( a) is a diagram showing part (b) of FIG. 33 in further detail, (b) is a diagram showing an equivalent data structure for ECC encoding/decoding, (c) is a diagram showing a mathematical equation for EDC computation, and (d) is a diagram showing a mathematical equation for ECC computation:
FIG. 36( a) is a diagram showing a reproduced signal waveform according to the embodiment, and (b) is a diagram for explaining a dimensional accuracy of a stripe according to the embodiment;
In the first-half part (I) of the description, a detailed explanation will be given of the piracy prevention position information as a form of ID, followed by a brief explanation of how the information is converted into a barcode to complete an optical disk and how the optical disk is played back. In the second-half part (II), the technique for barcoding the piracy prevention position information will be described in further detail and in a concrete manner. More specifically, the first-half part (I) deals with (A) Manufacturing a disk, (B) Forming a marking by using laser light. (C) Reading the position information of the marking, (D) Encrypting the position information, converting the encrypted position information into a barcode, and writing the barcode in a pre-pit area of the optical disk in overwriting fashion, and (E) Playing back the optical disk on a player. The second-half part (II) first describes (A) Usefulness of the barcode for a laminated-type optical disk, then proceeds to (B) Barcoding the position information of the marking as a disk-unique ID, (C) Features of the barcode-recorded optical disk format, methods of tracking control, and methods of rotational speed control during reading of the barcode, and (D) Playing back the barcode-recorded optical disk. The second-half part (II) further deals in detail with (E) Manufacturing techniques for implementing the-barcode recording method, followed by a brief explanation of a barcode playback apparatus (player). Finally, a description is given of (F) An example of the above barcode encryption and another application example of the barcode.
First, the software company performs software authoring in software production process 820. The completed software is delivered from the software company to the disk manufacturing factory. In disk manufacturing process 816 at the disk manufacturing factory, the completed software is input in step 818 a, a master disk is produced (step 818 b), disks are pressed (steps 818 e, 818 g), reflective films are formed on the respective disks (steps 818 f, 818 b), the two disks are laminated together (step 818 i), and a ROM disk such as a DVD or CD is completed (step 818 m, etc.).
The thus completed disk 800 is delivered to the software maker or to a factory under control of the software maker, where, in secondary recording process 817, an anti-piracy marking 584, such the one shown in FIG. 2, is formed (step 81 a), and accurate position information of this mark is read by a measuring means (step 819 b) to obtain the position information which serves as the physical feature information of the disk. This physical feature information of the disk is encrypted in step 819 c. The encrypted information is converted to a PE-RZ-modulated signal which is then recorded in step 819 d as a barcode signal on the disk by using a laser. The disk physical feature information may be combined together with software feature information for encryption in step 819 c. The above processes will be described in further detail. That is, a disk fabrication process, a marking formation process, a marking position reading process, and an encrypted information writing process for an optical disk according to the present invention will be described in detail with reference to FIGS. 4 and 5 and FIGS. 8 to 12. A supplementary explanation will also be given dealing with a disk having two reflective layers with reference to FIGS. 6 and 7. In the following description, the marking formation process and the marking position reading process are collectively called the secondary recording process.
At the rising edge of the thus obtained marking detection signal, a specific address (indicated by address n in FIG. 5( d)) is read by the optical pickup from within the plurality of addresses shown in FIG. 5( d). FIG. 5( b) shows the physical location of the specific address in schematic form On the other hand, FIG. 5( e) shows the logical structure of the data. As shown in FIG. 5( e), there are m frame synchronization signals under address n, and k reproduced clock pulses under each frame synchronization signal. Therefore, the position of the marking measured by the optical pickup can be represented by address, frame synchronization signal number, and reproduced clock count.
FIGS. 4 and 5 showed a disk generally known as a single-layer laminated disk which has a reflective layer only on one substrate 801. On the other hand, FIGS. 6 and 7 show a disk generally known as a two-layer laminated disk which has reflective layers on both substrates 801 and 803. For laser trimming, the processing steps (5) and (6) are fundamentally the same for both types of disks, except with significant differences which are briefly described below. First, while the single-layer disk uses a reflective layer formed from an aluminum film having reflectivity as high as 70% or over, in the two-layer disk the reflective layer 801 formed on the reading-side substrate 801 is a semitransparent gold (Au) film having a reflectivity of 30%, while the reflective layer 802 formed on the print-side substrate 803 is the same as that used in the single-layer disk. Second, as compared with the single-layer disk, the two-layer disk is required to have high optical accuracy; for example, the adhesive layer 804 must be optically transparent and be uniform in thickness, and the optical transparency must not be lost due to laser trimming.
(a) Using a 5 μj/pulse YAG laser, a laser beam was applied to a 500 angstrom aluminum layer lying 0.6 mm below the surface of a 1.2 mm thick ROM disk consisting of two 0.6 mm thick disks laminated together, and, as a result, a 12 μm wide slit-like nonreflective portion 815 was formed, as shown in the X 750 micrograph of FIG. 8( a). In this X 750 micrograph, no aluminum residues were observed on the nonreflective portion 815. Thick swollen aluminum layers, 2000 angstroms thick and 2 μm wide, were observed along boundaries between the nonreflective portion 815 and reflective portions. As shown in FIG. 10( a), it was confirmed that no significant damage had occurred inside. In this case, the application of the pulsed laser presumably melted the aluminum reflective layer, causing a phenomenon of molten aluminum buildup along the boundaries on both sides due to the surface tension. We call this a hot melt surface tension (HMST) recording method. This is a characteristic phenomenon observed only on a laminated disk 800. FIG. 11 is a schematic diagram, based on an observation through a transmission electron microscope (TEM), illustrating a cross section of the nonreflective portion formed by the above laser trimming process. And FIG. 11 shows that the adhesive layer of the disk has been removed by using solvent.
In the figure, if the aluminum film swollen portion is 1.3 μm wide and 0.20 μm thick, the amount of increased aluminum in that portion is 1.3�(0.20�0.05)=0.195 μm2. The amount of aluminum originally deposited in a half portion (5 μm) of the laser exposed region (10 μm) was 5�0.05=0.250 μm2. The difference is calculated as 0.250�0.195=0.055 μm2. In terms of length, this is equivalent to 0.055/0.05=1.1 μm. This means that an aluminum layer of 0.05 μm thickness and 1.1 μm length remained, and therefore, it can be safely said that almost all aluminum was drawn to the film swollen portion. Thus, the result of the analysis of the figure also verifies the explanation about the above-described characteristic phenomenon.
(c) A comparison between single-plate disk and laminated disk has been described above, using a two-layer laminated disk as an example. As is apparent from the above description, the same effect as obtained with the two-layer laminated disk can be obtained with the single-layer laminated disk. Using FIGS. 12( a), 12(b), etc., a further description will be given dealing with the single-layer laminated disk type. As shown in FIG. 12( a), the reflective layer 802 has the transparent substrate 801 of polycarbonate on one side, and the hardened adhesive layer 804 and a substrate on the other side, the reflective layer 802 thus being hermetically sealed therebetween. In this condition, pulsed laser light is focused thereon for heating; in the case of our experiment, heat of 5 μJ/pulse is applied to a circular spot of 10 to 20 μm diameter on the reflective layer 802 for a short period of 70 ns. As a result, the temperature instantly rises to 600� C., the melting point, melting state is caused. By heat transfer, a small portion of the transparent substrate 801 near the spot is melted, and also a portion of the adhesive layer 804 is melted. The molted aluminum in this state is caused by surface tension to build up along boundaries 821 a and 821 b, with tension being applied to both sides, thus forming buildups 822 a and 822 b of hardened aluminum, as shown in FIG. 12( b). The nonreflective portion 584 free from aluminum residues is thus formed. This shows that a clearly defined nonreflective portion 584 can be obtained by laser-trimming the laminated disk as shown in FIGS. 10( a) and 12(a). Exposure of the reflective layer to the outside environment due to a damaged protective layer, which was the case with the single-plate type, was not observed even when the laser power was increased more than 10 times the optimum value. After the laser trimming, the nonreflective layer 584 has the structure shown in FIG. 12( b) where it is sandwiched between the two transparent substrates 801, 803 and sealed with the adhesive layer-804 against the outside environment, thus producing the effect of protecting the structure from environmental effects.
As shown in FIG. 15, the disk 800 is loaded into a marking reading apparatus equipped with a low reflectivity position detector 600 to read the marking, and in this case, since a signal waveform 823 due-to the presence and absence of pits and a signal waveform 824 due to the presence of the nonreflective portion 584 are significantly different in signal level, as shown in the waveform diagram of FIG. 9( a), they can be clearly distinguished using a simple circuit.
The circuit delay time varies with reproduction apparatus used for reading, which means that the reference delay time TD varies depending on the reproduction apparatus used. Therefore, using the TD, a time delay corrector 607 applies time correction, and the resulting effect is that the start clock count for the low reflectivity portion can be measured accurately if reproduction apparatus of different designs are used for reading. Next, by finding the clock count and the start and end addresses for the optical mark No. 1 in the next track, clock m+14 at address n+12 is obtained, as shown in FIG. 16(8). Since TD=m+2, the clock count is corrected to 12, but for convenience of explanation, n+14 is used. We will describe another method, which eliminates the effects of varying delay times without having to obtain the reference delay time TD in the reproduction apparatus used for reading. This method can check whether the disk is a legitimate disk or not by checking whether the positional relationship of mark 1 at address n in FIG. 16(8) relative to another mark 2 matches or not. That is, TD is ignored as a variable, and the difference between the position, A1=a1+TD, of mark 1 measured and the position, A2=a2+TD, of mark 2 measured is obtained, which is given as A1−A2=a1−a2. At the same time, it is checked whether this difference matches the difference, a1−a2, between the position a1 of the decrypted mark 1 and the position information a2 of the mark 2, thereby judging whether the disk is a legitimate disk or not. The effect of this method is that the positions can be checked after compensating for variations of the reference delay time TD by using a simpler constitution
(D) Next, the encrypted information writing process will be described. The position information read in the process (C) is first converted into ciphertext or �signed� with a digital signature. Then, the marking position information thus encrypted or signed is converted into a barcode as an ID unique to the optical disk, and the barcode is recorded in overwriting fashion in a prescribed region of a pre-pit area on the optical disk Barcode patterns 584 c�584 e in FIG. 2( a) indicate the barcode written to the prescribed region of the pre-pit area, that is, in the innermost portion of the pre-pit area.
On the other hand, when the marking position information was recorded as a barcode by laser trimming on the laminated-type disk of the invention formed from two transparent substrates laminated together, it was confirmed that the protective layer 804 remained almost unchanged, as already explained in connection with FIG. 10( a). This was confirmed by experiment by observing the disk under an optical-microscope of 800� magnification. It was also confirmed that no change had occurred to the reflective film in the trimmed portion after an environmental test of 96 hours at a temperature of 85� C. and a humidity of 95%.
In the conventional NRZ recording, the pulse widths are 1T and 2T, as shown in parts (1) and (3) of FIG. 25; it is therefore apparent that NRZ recording is not suitable for the laser trimming of the present invention. According to the laser trimming of the present invention, a barcode is formed as shown in the experiment result shown in FIG. 8( a), but since trimming line width differs from disk to disk, it is difficult to precisely control the line width; when trimming the reflective film on a disk, the trimming line width varies depending on variations in laser output, thickness and material of the reflective film, and thermal conductivity and thickness of the substrate. Further, forming slots of different line widths on the same disk will result in an increased complexity of the recording apparatus. For example, in the case of the NZR recording used for product barcode recording, as shown in parts (1) and (2) of FIG. 25, the trimming line width must be made to precisely coincide with the period 1T of the clock signal, or 2T or 3T, that is, with nT. It is particularly difficult to record various line widths such as 2T and 3T by varying the line width for each bar (each stripe). Since the conventional product barcode format is an NRZ format, if this format is applied to the laser-recorded barcode of the present invention, the fabrication yield will decrease because it is difficult to precisely record varying line widths such as 2T and 2T on the same disk; furthermore, stable recording cannot be done since the laser trimming width varies. This makes demodulation difficult. Using RZ recording, the present invention has the effect of achieving stable digital recording even if the laser trimming width varies. Furthers the invention offers the effect of simplifying the construction of the recording apparatus since RZ recording requires only one kind of line width and the laser power therefore need not be modulated.
A circular barcode, such as shown in FIG. 27(1), is thus formed on the disk. When data �01000�, shown in part FIG. 27(4), is recorded, in the PE-RZ modulation of the invention a barcode 923 a having the same pattern as the recorded signal shown in part (3) is recorded as shown in part (2). When this barcode is played back by an optical pickup, a signal waveform, such as shown in part (5) REPRODUCED SIGNAL, is output with portions thereof dropped corresponding to missing portions of a pit-modulated signal where no reflection signals are obtained due to removal of the reflective film, as explained with reference to part FIG. 5(6). By passing this reproduced signal through the second-order or third-order LPF filter 934 shown in FIG. 35( a), the filtered signal waveform shown in FIG. 27(6) is obtained. By slicing this signal by a level slicer, reproduced data �0000� of part (7) is demodulated.
A signal from the optical head is first subjected to waveshaping, and then the pulse spacing of the pit signal is measured by an edge-spacing measuring means 953. A t0 reference value generating means 956 generates reference value information t0 whose pulse width is larger than the pulse width 14T of the sync signal but smaller than the pulse width t of the barcode signal. This reference value information t0 and the pulse width TR of the reproduced signal are compared in a comparing means 954; only when TR is smaller than the reference value t0 and larger than Tmax held in a memory means 955, TR is supplied to the memory means 955 where TR is set as Tmax. By reference to this Tmax, a controller 957 controls a motor drive circuit 958, achieving motor rotational speed control based on Tmax. In the case of the present invention, numerous pulses at cycles of 3 to 10 μs are generated by barcode stripes, as shown in FIG. 9( a). In the case of a DVD, the sync pulse width is 14T, that is, 1.82 μm. On the other hand, the barcode stripe width is 15 μm. In Tmax-based control, the barcode pulse longer than the pulse width 14T of the synch pulse will be erroneously judged and detected as Tmax. Therefore, by removing barcode signals larger than the reference value t0 by comparison with the reference value t0, as shown in FIG. 41, it becomes possible to perform rotational speed control for normal rotational speed during the playback of the barcode stripe area.
In the present invention, as shown in FIG. 30, the control data recorded in the control data area 936 of the optical disk contains a PCA stripe presence/absence identifier 937 recorded as a pit signal. Therefore, the optical head is first moved in step 940 n, to an outer area where the control data is recorded. And then the optical head moves inwardly jumping across a plurality of tracks until reaching the control data area 436. And then in step 940 a, the control data is played back. It can thus be checked whether the stripes are recorded or not. If, in step 940 b, the stripe presence/absence identifier is 0, the process proceeds to step 940 f to initiate rotation phase control for normal playback with CLV. On the other hand, if, in step 940 b, the presence/absence identifier 937 is 1, then the process proceeds to step 940 h to check the presence or absence of a reverse-side record identifier 948 which indicates that the stripes are recorded on the side opposite from the side being played back, that is, on the reverse side. If the stripes are recorded on the reverse side, the process proceeds to step 940 i to play back the recording surface on the reverse side of the optical disk. If the reverse side cannot be automatically played back, an indication is output for display, to urge the user to turn over the disk. If it is determined in step 940 h that the stripes are recorded on the side being played back, the process proceeds to step 940 c, where the head is moved to the stripe area 923 in the inner portion of the disk, and in step 940 d, the control mode is switched to rotational speed control to play back the stripes 923 with CAV rotation. If the playback is completed in step 940 e, then in step 940 f the control mode is switched back to rotation phase control for CLV playback and the optical head is moved to the outer portion of the disk to play back pit signal data.
Then the optical head accesses the control data from the outer portion of the disk, the optical head moves inwardly jumping across a plurality of tracks until reaching the control data area 936. In some cases, the optical head may be moved past the destination control data area 936, landing at a portion further inward of the control data area. At this time, if the PCA area 998 exists directly adjacent to the inner circumference of the control data area, the optical head will lose its own position since an address cannot be played back in the PCA area 998. It, then, becomes impossible to control the optical head.
When the duty ratio of the stripe on the optical disk, that is, its area ratio, is low, almost correct tracking can be maintained in the stripe area as shown in FIG. 32. Therefore, the address information in the address area 944 at the same radius position of the disk can be played back. This has the effect of quickening the disk rise time after disk insertion since the address can be played back while playing back the stripes without changing the optical head position.
In this case, the address area an area where no stripes are recorded, should be formed continuously along a length longer than one frame in the same radium portion of the disk.
(E) Next, manufacturing techniques for implementing the optical disk barcode forming method of the-invention will be described in further detail. A barcode playback apparatus will also be described briefly.
In the case of the barcode recording method previously explained with reference to FIG. 28, the minimum emitting-pulse spacing is lt; therefore, a laser with a pulse repetition period of fC=1/fL is required, where fL is the frequency of the laser. In this case, the number, fL/2, of barcode bars can be recorded per second. However, if a beam deflector 931 is used as shown in FIG. 29, a minimum emitting-pulse spacing of 2t is allowed, so that the pulse repetition period is fL=1/2t, which means that the laser frequency can be reduced by a factor of 2. This also means that, when a laser of the same frequency is used, the number of barcode bars that can be recorded per second can be doubled to fL by using the beam deflector 931. This has the effect of reducing the productive tact (processing tact) by a factor of 2.
The operation of a double-efficiency apparatus (referred to as �switch recording�) using the beam deflector 931 will be described below with reference to FIG. 29, focusing-on differences from the configuration of FIG. 28.
The beam deflector 931, formed from an acousto-optical modulator or the like, is supplied with a deflection signal for switching the beam between a main beam 945 and a sub-beam 946; when the deflection signal is ON, the beam is switched to the sub-beam 946 which is passed through a subslit 932 b and forms a sub-stripe 934. More specifically, for data �0� a normal stripe 933 is formed; only when recording data �1� is the deflection signal set to ON, as shown in FIG. 29( b), in response to which the beam deflector 931 switches the beam to the sub-beam 946 to record a stripe at the position of the sub-stripe 934. In this manner, stripes 933 a and 933 b, each for �0�, and a stripe 934 a for �1�, as shown in part (b), are formed on the disk. In this configuration, since a laser pulse need only be produced at intervals of 2t, a laser with a frequency half that required in the configuration of FIG. 28 can be used. In other words, when a laser of the same frequency is used, since the stripes can be formed at twice the clock frequency, this has the effect of increasing the productivity by a factor of 2, as already described.
First, to achieve the switch recording of FIG. 29, provisions must be made so that two or more pulses will not occur within one time slot, that is, within 1T interval. Switch recording is possible in the data area because data is recorded there with a PE-RZ code, as shown in FIG. 33( a). However, in the case of the synchronization code of FIG. 34( a), since irregular channel bits are arranged, with the usual method two pulses may occur within 1T, in which case the switch recording of the invention is not possible. To address this problem, the invention employs, for example, the bit pattern �01000110� as shown in FIG. 37. With this bit pattern, in T1 a pulse occurs for the �1� on the right, in T2 no pulses occur, in T3 a pulse occurs for the �1� on the right, and in T4 a pulse occurs for the �1� on the left; in this way, two or more pulses cannot occur within one time slot. Thus, the synchronization code structure of the invention has the effect of achieving switch recording increasing the production rate by a factor of 2.
In the present invention, the interleaving and Reed-Solomon error-correction coding shown in the data structure of FIG. 33( a) are performed using the ECC encoder 927 shown in FIG. 1 when recording stripes on an optical disk. With this error-correction method, a read error occurs in only one disk out of 107=10 million optical disks under the condition of that Byte error rate of 10−4 occurs, as shown in FIG. 33( c). In this data structure, to reduce the code data length the same sync code is assigned to four rows, reducing the number of sync codes by a factor of 4 and thus increasing efficiency. With further reference to FIG. 33, the scalability of the data structure will be described. In the present invention, the recording capacity can be varied freely, for example, within a range of 12B (12 Byte) to 188B in increments of 16B, as shown in the example of FIG. 34( c). That is, n can be changed within a range of n=1 to n=12, as shown in FIG. 33( c).
As shown in FIG. 33( b) and FIG. 14( a), for example, in the data structure when n=1, there are only four data rows 951 a, 951 b, 951 c, and 951 d, followed by ECG rows 952 a, 952 b, 952 c, and 952 d. FIG. 14( a) is a diagram showing FIG. 33( b) in further detail. The data row 951 constitutes EDC of 4B. FIG. 14( b) shows this in an equivalent form. Error-correction encoding computation is performed, assuming that data rows from 951 e to 951 z all contain 0s. Mathematical equations for EDC and ECC computations are shown in FIGS. 14( c) and 14(d), respectively. In this way, the data is ECC-encoded by the ECC encoder 927 in the recording apparatus of FIG. 1 and recorded as a barcode on the disk. When n=1, data of 12B is recorded over an angle of 51 degrees on the disk. Likewise, when n=2, data of 18B can be recorded; when n=12, data of 271B can be recorded over an angle of 336 degrees on the disk. In the present invention, by encoding and decoding the data using the EDC and ECC computation equations shown in FIGS. 14( c) and 14(d), when the data amount is smaller than 188B, the computation is performed assuming all remaining bits are 0s, so that the data is stored with a small recording capacity. This serves to shorten the productive tact. When performing laser trimming, as in the present invention, the above-described scalability has a significant meaning. More specifically, when performing laser trimming at a factory, it is important to shorten the productive tact. With a slow-speed apparatus which trims one stripe at a time, it will take more than 10 seconds to record a few thousand stripes to the full capacity. The time required for disk production is 4 seconds per disk; if full-capacity recording has to be done, the productive tact increases. On the other hand, for the moment, disk ID number will be a main application area of the present invention; in this application, the PGA area capacity can be as low as 10B. If 271B are recorded when only 10B need to be written, the laser processing time will increase by a factor of 6, leading to a production cost increase. The scalability method of the present invention achieves reductions in production costs and time.
In the playback apparatus shown in FIG. 15, when n=1 as in FIG. 33( b), for example, the ECC decoder 928 performs the EDC and ECC error correction computations shown in FIGS. 14( c) and 14(d), assuming that the data rows 951 e to 951 z all contain 0s; the effect of this is that data of 12 to 271B can be corrected for errors by using the same program. In this case, the number or program steps decreases, permitting the use of a small-capacity ROM in the microcomputer.
(d) As described above, with the first method that involves laser trimming, it is difficult to process with a submicron accuracy, and therefore, it is difficult to mass produce pirated disks. On the other hand, with the second method using the submicron processing technology such as X-ray exposure, the cost per disk is so high that making p-rated disks is meaningless from an economic point of view. Accordingly, making illegal copies can be prevented until some day in the future when low-cost submicron processing technology for mass production becomes practical. Since practical implementation of such technology will be many years into the future, production of pirated disks can be prevented. In the case of a two-layer disk with a low reflectivity portion formed on each layer as shown in FIG. 33, an illegally duplicated disk cannot be manufactured unless the pits on top and bottom are aligned with good accuracy when laminating, and this enhances the effectiveness in preventing piracy.
In the present invention, sufficient effectiveness in piracy prevention is provided by the reflective layer level mechanism, that is, by the low reflective marking alone. In this case, the prevention is effective even if the master disk is a duplicate. However, the effectiveness can be enhanced by combining it with the piracy prevention technique at the master disk level. If the arrangement angle of the low reflectivity portion on the disk is specified as shown in Table 532 a and Table 609 in FIG. 13( a), an illegal manufacturer would have to accurately duplicate even the arrangement angle of each pit on the master disk. This would increase the cost of pirated disks and hence enhance the capability to deter piracy.
FIG. 19 shows a flowchart for detecting a duplicated CD by using the low reflectivity portion address table. The delay time needed to detect the optical mark varies only slightly due to the optical head and circuit designs of the reproduction apparatus used. This of the delay time TD circuit can be predicted at the design stage or at the time of mass production. The optical mark position information is obtained by measuring the number of clocks, that is, the time, from the frame synchronizing signal. Due to the effect of the circuit delay time, an error may be caused to detected data of the optical mark position information. As a result, a legitimate disk may be erroneously judged as being a pirated disk, inconveniencing a legitimate user. A measure to reduce the effect of the circuit delay time TD will be described below. Further, a scratch made on a disk after purchase may cause an interruption in the reproduced clock signal, causing an error of a few clocks in the measurement of the optical mark position information. To address this problem, a tolerance 866 and a pass count 867, shown in FIG. 20, are recorded on a disk, and while allowing a certain degree of tolerance on the measured value according to the actual situation at the time of reproduction the reproduction operation is permitted when the pass count 867 is reached; the margin allowed for an error due to a surface scratch on the disk can be controlled by the copyright owner prior to the shipment of the disk. This will be described with reference to FIG. 19.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS4677604Feb 4, 1985Jun 30, 1987Selsys CorporationMethod for controlling access to recorded dataUS4703469Apr 9, 1984Oct 27, 1987Plasmon Data Systems, P.V.Optical data recording using radiation of different characteristicsUS4855581 *Jun 17, 1988Aug 8, 1989Microscan Systems IncorporatedDecoding of barcodes by preprocessing scan dataUS4972399Sep 8, 1988Nov 20, 1990Kabushiki Kaisha ToshibaApparatus and method for accessing a disk characteristic data recording area of an optical diskUS5065429Oct 14, 1990Nov 12, 1991Lang Gerald SMethod and apparatus for protecting material on storage mediaUS5150339Apr 20, 1990Sep 22, 1992Hitachi, Ltd.Optical disk medium and its application method and systemUS5155722Sep 20, 1990Oct 13, 1992Kabushiki Kaisha ToshibaRecording/reproducing apparatusUS5191611Jan 18, 1991Mar 2, 1993Lang Gerald SMethod and apparatus for protecting material on storage media and for transferring material on storage media to various recipientsUS5250787Sep 12, 1989Oct 5, 1993Matsushita Electric Industrial Co., Ltd.Optical-disk playback apparatus, method of optical-disk playback and combined memory medium, having control programs stored in the optical-disc and specified by barcodes stored in a barcode memory mediumUS5371792Dec 21, 1993Dec 6, 1994Kabushkuki Kaisha Sega EnterprisesCD-ROM disk and security check method for the sameUS5392351Mar 15, 1993Feb 21, 1995Fujitsu LimitedElectronic data protection systemUS5400403Aug 16, 1993Mar 21, 1995Rsa Data Security, Inc.Abuse-resistant object distribution system and methodUS5430281Feb 28, 1994Jul 4, 1995Eastman Kodak CompanyStorage media for an optical information system having an identification code embedded thereinUS5457668Dec 21, 1992Oct 10, 1995Nintendo Co., Ltd.Data processing system with collating processing at start up for determining the presence of an improper optical CDUS5457746Dec 19, 1994Oct 10, 1995Spyrus, Inc.System and method for access control for portable data storage mediaUS5473148 *Aug 8, 1994Dec 5, 1995Olympus Optical Co., Ltd.Barcode symbol reading system capable of shortening time for reading and decodingUS5489768Dec 31, 1992Feb 6, 1996Eastman Kodak CompanyApparatus and method for data security in an optical disk storage systemUS5513169Nov 29, 1994Apr 30, 1996Sony CorporationCD-ROM with machine-readable i.d. codeUS5521368 *Aug 11, 1994May 28, 1996Olympus Optical Co., Ltd.Barcode symbol reading system having function for detecting and correcting inclination of barcode symbolUS5587984Sep 8, 1995Dec 24, 1996Sony CorporationHologram printed on optical recording medium for copy protectionUS5696757Sep 23, 1996Dec 9, 1997Victor Company Of Japan, Ltd.Optical disc, device for checking optical disc and device for recording information on optical discUS5698833Apr 15, 1996Dec 16, 1997United Parcel Service Of America, Inc.Omnidirectional barcode locatorUS5706047Apr 24, 1995Jan 6, 1998Eastman Kodak CompanyStorage media for an optical information system having an identification code embedded thereinUS5706266May 1, 1995Jan 6, 1998Eastman Kodak CompanyApparatus and method for data security in an optical disk storage systemUS5714935Feb 3, 1995Feb 3, 1998Sensormatic Electronics CorporationArticle of merchandise with concealed EAS marker and EAS warning logoUS5754649Jun 23, 1997May 19, 1998Macrovision Corp.Video media security and tracking systemUS5761301Nov 17, 1995Jun 2, 1998Matsushita Electric Industrial Co., Ltd.Mark forming apparatus, method of forming laser mark on optical disk, reproducing apparatus, optical disk and method of producing optical diskUS5807640Dec 28, 1994Sep 15, 1998Matsushita Electric Industrial Co., Ltd.Optical recording medium, reproducing system, method of reproducing optical disk, method of fabricating optical disk original record, and method of stopping illegal program operationUS5822291Nov 21, 1995Oct 13, 1998Zoom Television, Inc.Mass storage element and drive unit thereforUS5826156Feb 27, 1997Oct 20, 1998Minolta Co., Ltd.Image forming apparatusUS5905798May 2, 1997May 18, 1999Texas Instruments IncorporatedTIRIS based kernal for protection of "copyrighted" program materialUS6052465May 16, 1996Apr 18, 2000Matsushita Electric Industrial Co., Ltd.Optical disk, an optical disk barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical diskUS6083667 *Jan 23, 1998Jul 4, 2000Victor Company Of Japan, Ltd.Optical recording mediumUS20020097871Feb 20, 2002Jul 25, 2002Yoshiho GotohOptical disk, an optical disk barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical diskDE4308680A1Mar 18, 1993Oct 28, 1993Fujitsu LtdPreventing unauthorised use of optical disc e.g. CD-ROM - comparing first information read out from area of disc inaccessible to user with second information concerning authentic diskEP0545472A1Nov 25, 1992Jun 9, 1993Philips Electronics N.V.Closed information system with physical copy protectionEP0549488A1Dec 14, 1992Jun 30, 1993Eastman Kodak CompanyA storage media for an optical information system having an identification code embedded thereinEP0553545A2Oct 28, 1992Aug 4, 1993Kabushiki Kaisha Sega EnterprisesCD-ROM disk and security check method for the sameEP0741382A1Nov 16, 1995Nov 6, 1996Matsushita Electric Industrial Co., Ltd.Marking generating apparatus, method of forming laser marking on optical disk, reproducing apparatus, optical disk and optical disk producing methodJPH027243A Title not availableJPH0244448A Title not availableJPH0256750A Title not availableJPH0562363A Title not availableJPH0785574A Title not availableJPH01268232A Title not availableJPH02232831A Title not availableJPH04162224A Title not availableJPH04178967A Title not availableJPH05266576A Title not availableJPH05325193A Title not availableJPH06203412A Title not availableJPH07121907A Title not availableJPH07325712A Title not availableJPH08102133A Title not availableJPS5625242A Title not availableJPS6171487A Title not availableJPS6346541A Title not availableJPS58211343A Title not availableJPS60193143A Title not availableJPS61190734A Title not availableJPS63164043A Title not availableJPS63298717A Title not availableNL9101358A Title not availableWO1995028704A1Apr 18, 1995Oct 26, 1995Matsushita Electric Ind Co LtdMethod and apparatus for preventing illegal copying and illegal installation of information on optical recording medium* Cited by examinerNon-Patent CitationsReference1European Search Report corresponding to application No. 96915172.9 dated Oct. 22, 1997.2European Search Report dated May 15, 1997, application No. 95-938017.3Japanese Office Action, issued in corresponding Japanese Patent Application No. 11-257247, dated Sep. 25, 2001.4Japanese Search Report dated Jan. 30, 1996, application No. 95-02339.5Japanese Search Report dated Sep. 3, 1996.6Japanese Search Report, application No. 11-257249 dated Feb 29, 2000.7Japanese Search Report, application No. 11-257250, dated Feb. 29, 2000.8Japanese Search Report, application No. 11-257251, dated Feb. 29, 2000.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS8014236 *Mar 4, 2009Sep 6, 2011Panasonic CorporationOptical disk, an optical disk barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical diskUS8472291Jul 29, 2011Jun 25, 2013Panasonic CorporationOptical disk, an optical disk barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical disk* Cited by examinerClassifications U.S. Classification369/59.23, 369/47.21, G9B/7.194, G9B/20.002, G9B/7.033, G9B/23.092, G9B/23.006, G9B/20.027, G9B/27.027, 369/53.41, G9B/7.029, G9B/20.03, G9B/19.005, G9B/23.088, G9B/19.017, G9B/23.087, G9B/19.018, G9B/20.009International ClassificationG11B7/00, H04L9/10, G11B7/004, G11B7/24, G11B7/005, G11B7/09, G11B13/04, G11B7/0055, G06F1/00, G11B19/06, G11B23/28, G06K19/08, G11B7/26, G06K1/12, G11B19/04, G11B20/12, G06K19/06, G11B27/36, G11B20/00, G11B20/10, G11B23/30, G11B20/18, G11B23/38, G11B7/007, G11B7/0037, G11B19/12, G11B23/00, G11B5/86, G06K19/04, G06K19/14, G11B27/24, G11B20/14Cooperative ClassificationG06K1/126, G11B23/283, G11B19/12, G06K19/04, G11B20/00586, G06K19/06018, G11B20/1833, G11B2007/0013, G11B20/1403, G11B2020/122, G11B20/1419, G11B27/24, G11B7/0037, G06K2019/06243, G06K19/08, G11B2220/61, G11B20/00144, G11B7/00736, G11B7/268, G11B20/00152, G11B7/007, G11B20/00123, G11B7/26, G11B20/00094, G11B20/0092, G11B20/00855, G11B20/0021, G11B20/10, G11B23/0042, G11B23/284, G11B20/00557, G11B13/04, G11B5/86, G11B23/34, G11B23/281, G11B20/00492, G11B2220/2545, G11B20/1217, G11B20/1252, G11B19/122, G11B7/005, G11B23/30, G11B20/00876, G06K19/06028, G11B20/1426, G11B23/38, G11B20/00384, G11B20/00115, G11B20/00528, G11B20/00086, G11B7/24038, G11B20/00268, G11B19/04, G11B2220/213, G11B20/0026, G11B20/00347, G11B20/00326, G06K2019/06271, G11B20/0071, G11B2220/2562, G11B2020/1259, G11B7/0053, G11B20/00137, G11B13/045, G11B20/0084, G06K19/14, G11B20/00543European ClassificationG06K19/06C1, G11B20/00P5A6A1, G11B20/00P2B, G11B20/00P12, G11B20/00P5, G11B20/00P5A6H, G11B20/00P13, G11B20/00P2, G11B20/00P5G2, G11B20/00P1C, G11B20/00P5A6M, G11B23/28B2, G11B20/14A1D, G11B20/00P1D, G11B20/00P5G5, G11B23/28B, G11B20/00P2A, G11B23/34, G11B20/00P10, G11B20/00P5A6A, G11B20/00P5G1E, G11B20/00P5A6E, G11B7/26V, G11B20/00P11E, G11B20/00P1, G11B7/24038, G11B20/00P6B, G11B7/005W, G11B20/00P5G1, G11B20/00P15, G11B20/00P, G11B7/007R, G11B19/04, G11B23/30, G11B20/10, G11B19/12, G11B20/12D6, G06K19/06C1B, G06K19/08, G06K19/04, G11B7/26, G11B27/24, G11B23/00D1A2A, G11B20/12D, G11B19/12C, G06K19/14, G06K1/12D, G11B23/38, G11B7/007, G11B23/28ALegal EventsDateCodeEventDescriptionJan 22, 2014FPAYFee paymentYear of fee payment: 8Jan 29, 2010FPAYFee paymentYear of fee payment: 4Sep 4, 2007CCCertificate of correctionRotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services