WO2000065581A1 - Apparatus and method for scanning a rotating information carrier - Google Patents
Apparatus and method for scanning a rotating information carrier Download PDFInfo
- Publication number
- WO2000065581A1 WO2000065581A1 PCT/EP2000/003523 EP0003523W WO0065581A1 WO 2000065581 A1 WO2000065581 A1 WO 2000065581A1 EP 0003523 W EP0003523 W EP 0003523W WO 0065581 A1 WO0065581 A1 WO 0065581A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- track
- information carrier
- scanning
- scanning point
- point
- Prior art date
Links
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
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/085—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam into, or out of, its operative position or across tracks, otherwise than during the transducing operation, e.g. for adjustment or preliminary positioning or track change or selection
- G11B7/08505—Methods for track change, selection or preliminary positioning by moving the head
-
- 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
- G11B7/004—Recording, reproducing or erasing methods; Read, write or erase circuits therefor
- G11B7/0045—Recording
-
- 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
- G11B7/004—Recording, reproducing or erasing methods; Read, write or erase circuits therefor
- G11B7/005—Reproducing
Definitions
- the invention relates to an apparatus for scanning a rotating information carrier, which information carrier has mutually substantially parallel tracks for the recording of information, which apparatus includes a transducer for scanning the information carrier and generating a position signal which is indicative of the position of a scanning point of the information carrier, which point is scanned by the transducer, means for rotating the information carrier about an axis, and means for moving the scanning point radially with respect to the axis.
- the invention further relates to a method for scanning a rotating information carrier.
- Such an apparatus is known from US 5,321,676.
- the known apparatus has coarse positioning means in the form of a slide carrying the transducer and a motor for driving the slide and has fine positioning means for positioning the scanning point with respect to the transducer.
- the apparatus is suitable for reading information carriers having tracks which together form a spiral.
- the scanning means cause the scanning point to follow the track.
- the position of the fine positioning means is corrected continually.
- a signal indicative of the position of the fine positioning means exceeds a threshold value the transducer is moved stepwise.
- rotational latency time it takes some time, hereinafter referred to as rotational latency time, until the rotational position of the starting point and that of the scanning point coincide.
- rotational latency time it is desired to have a minimal rotational latency time.
- the apparatus in accordance with the invention is characterized in that the apparatus has a scanning mode in which during reading and/or writing of a continuous file the scanning point is moved both from one track to another track in a first radial direction and from one track to another track in a second radial direction opposite thereto.
- a signal is generated which is indicative of the position of a scanning point of the information carrier, the information carrier being rotated about an axis and the scanning point being moved in a direction transverse to the axis
- which method comprises a scanning mode in which during reading and/or writing of a continuous file the scanning point is moved both from one track to another track in a first radial direction and from one track to another track in a second radial direction opposite thereto.
- reading and/or writing of file information is started at the tangential position of the information carrier which instantaneously coincides with the tangential position of the scanning point immediately upon reception of the command in said scanning mode. Consequently, there is no rotational latency time. However, there may be a latency time during reading and/or writing of the file. As a rule, it is favorable to effect reading in accordance with said scanning mode if the information carrier should traverse a comparatively large angle before the tangential position of the starting point of the file has come within the range of the scanning point.
- a variant of the method in accordance with the invention is characterized in that in said scanning mode the scanning point moves one time in the first radial direction and subsequently moves more gradually in the second radial direction.
- This variant has the advantage that not many abrupt movements of the scanning point are required, which contributes to a low power consumption.
- Another variant of the method in accordance with the invention is characterized in that during every revolution the scanning point jumps from one track to another track in the first radial direction and jumps from one track to another track in the second radial direction.
- This variant enables information streams such as video/audio streams to be made available rapidly.
- An apparatus in accordance with the invention can choose from the various methods in accordance with the invention to scan the information carrier or can scan the information carrier in a conventional manner, i.e. sequentially.
- the choice from the different variants of the method in accordance with the invention and the conventional method may depend, for example, on the type of file, the type of information carrier (spiral /circular tracks), the instantaneous position of the information carrier relative to the transducer, and the permissible power consumption during the displacement of the transducer.
- the information carrier may be scanned for example in a conventional manner if the starting position of the file nearly coincides with the range of the transducer. In this situation there is no rotational latency time when the conventional method is used.
- the information may be stored, for example, as a magnetically or an optically detectable pattern.
- the tracks may be separate and concentric with respect to one another but alternatively they may together form a spiral.
- the method is particularly suitable for an information carrier as proposed in the format-C DVD-RNM, in which the tracks are divided into sectors having a header, sectors of mutually adjacent tracks having mutually the same tangential boundaries. Since mutually adjacent sectors have the same tangential boundaries the transducer can directly read a following sector upon a radial displacement at the end of a sector.
- the file to be read or written is for example a data file, an audio file or a video file or it includes information referring to other files.
- the apparatus has a buffer coupled to the transducer. This allows information of a file read from the information carrier in said scanning mode to be made available in a sequential order and/or information which is available in a sequential order to be arranged in the order in which it is written onto the information carrier.
- a favorable embodiment of the apparatus in accordance with the invention is characterized in that the means for moving the scanning point radially with respect to the axis include coarse positioning means and fine positioning means, jumping to an adjacent track being effected by the fine positioning means. This allows jumps to be made rapidly using little power.
- Figure 1 shows an embodiment of an apparatus in accordance with the invention
- Figure 2 shows a variant of a method in accordance with the invention
- Figure 3A shows a first information carrier, for which a path followed by the scanning point in the case of a method in accordance with the invention is indicated,
- Figure 3B graphically represents the relationship between the radial coordinate (R) of the scanning point and the angle ( ) traversed by the first information carrier for the path shown in Figure 3A,
- Figure 3C graphically represents the relationship between the radial coordinate (R) of the scanning point and the angle ( ⁇ ) traversed by the first information carrier shown in Figure 3 A in the case of a conventional method
- Figure 3D shows a first information carrier, for which a path followed by the scanning point in the case of a method in accordance with the invention is indicated,
- Figure 4A shows a second information carrier, for which a path followed by the scanning point in the case of a method in accordance with the invention is indicated,
- Figure 4B graphically represents the relationship between the radial coordinate (R) of the scanning point and the angle ( ⁇ ) traversed by the first information carrier for the path shown in Figure 4 A,
- Figure 5 graphically represents the relationship between the radial coordinate (R) of the scanning point and the angle ( ⁇ ) traversed by the first information carrier shown in Figure 3 A in the case of another method in accordance with the invention
- Figure 6A shows a second information carrier, for which a path followed by the scanning point in the case of another method in accordance with the invention is indicated
- Figure 6B graphically represents the relationship between the radial coordinate (R) of the scanning point and the angle ( ⁇ ) traversed by the information carrier for the path shown in Figure 6A.
- Figure 1 shows diagrammatically an apparatus for reading and/or writing information from/onto a rotating information carrier 1.
- the apparatus has a transducer 5 for the generation of a position signal Id. This signal provides an indication of a position of a scanning point 6 scanned by the transducer 5.
- the information carrier is a magnetic information carrier.
- the transducer is, for example, a magnetic head which generates an electric signal in response to a magnetic pattern recorded on the information carrier.
- the information carrier 1 is an optical information carrier.
- the transducer 5 has, for example, means for imaging a radiation beam onto the information carrier 1 and means for detecting radiation reflected from the information carrier.
- the apparatus 1 includes a motor 4 which forms means for rotating the information carrier 1 about an axis 3.
- the transducer 5 is carried by a slide 7, which is driven by a slide motor 11 via shaft 10.
- the slide 7, the shaft 10 and the slide motor 11 form coarse positioning means.
- the apparatus further has fine positioning means 8, which enable small excursions of the scanning point 6 to be made rapidly.
- the slide motor 11 and the motor for rotating the information carrier 1 are controlled by a control unit 12.
- the fine positioning means 8 are controlled by a servo control 9 and the control unit 12. With the aid of the fine positioning means 8 and the coarse positioning means 7, 10, 11 the scanning point 6 can be moved radially with respect to the axis 3.
- the apparatus shown in Figure 1 has a buffer 13 for receiving a write signal Sw and for applying the information provided by the write signal to the transducer in an order which corresponds to the order in which it is written onto the information carrier.
- the apparatus further has a buffer 14 for receiving a signal read by the transducer and for arranging the information furnished by this signal in a sequential order. Both buffers are controlled by the control unit 12.
- the invention relates to a method of scanning the information carrier when information is read and/or written. This can be realized by basically conventional means as shown in Figure 1. Therefore, the means shown do not require any further information. The manner in which information is read or written in the apparatus in accordance with the invention is described in more detail with reference to Figure 2.
- a first program section 20 is carried out to determine the coordinates of the starting position (R ⁇ , CX B ) of the file and the coordinates of the end position of the file (R ⁇ , OC B ).
- R E , OC E are the radial components of the relevant positions, i.e. the distance of the position to the axis 3.
- the tangential components (CX B , OC E ) of a position are defined as the angle to be traversed in the direction of rotation of the information carrier 1 until the relevant position lies within range of the scanning point.
- the scanning mode in accordance with which the file is to be read or written is chosen.
- the choice may depend, for example, on the type of file, the type of information carrier (spiral/circular tracks), the instantaneous position of the information carrier with respect to the transducer, and the permissible power consumption during the displacement of the transducer. If only a small rotational latency time is required before the starting position (R ⁇ , CX B ) of the file has come within the range of the scanning point 6, the program proceeds to a third program section 40.
- This program section 40 causes the file to be read or written sequentially in accordance with a first scanning mode. This scanning mode will not be described in further detail because it is a customary method of scanning.
- a second scanning mode in accordance with a fourth program section having program steps 50-58 or a third scanning mode in accordance with a fifth program section hav g program steps 6-63 can be carried out.
- the scanning point jumps from one track to another track in the first radial direction and from one track to another track in the second radial direction, which is opposite thereto, during every revolution in the second scanning mode. In the present case the scanning point jumps inward at an angle . and outward at an angle ⁇ +.
- the second scanning mode is particularly suitable if an information stream, such as an audio stream or a video stream, is to be read rapidly.
- the scanning point moves once in the first radial direction and subsequently moves more gradually in the second radial direction during reading/writing in the third scanning mode.
- the third scanning mode has the advantage that the number of jumps of the scanning point and, consequently, the required power consumption is limited.
- the fourth program section 50-58 has a first program step 50, in which the scanning point 6 is positioned on a track which carries files information or is to be inscribed with file information at the instantaneous angle of the information carrier 1.
- a second program step 51 of the fourth program section it is determined whether the current track is the last track which forms part of the file to be read or written. If this is not the case a first series of program steps 52-55 is carried out.
- program step 55 the scanning point 6 jumps to an adjacent track which is remoter from the axis 3.
- the first series of program steps 52-55 is repeated.
- the angles ⁇ . and ⁇ + may be adapted each time after the series has been carried out. This is explained with reference to Figure 3D.
- a second series of program steps 56-58 is carried out.
- the fifth program section 60-63 which describes the third scanning mode, has a first program step 60 in which the scanning point is first moved to the outermost track assigned to the file. Subsequently, this track is followed in program step 61 until the starting position (R ⁇ , C B ) is within the range of the scanning point 6.
- the scanning point is made to move in the first radial direction, in this case in the inward direction.
- the program step 63 the remainder of the file is read sequentially, the scanning point being moved more gradually in the opposite radial direction.
- Figure 3A shows diagrammatically an information carrier 1 having tracks 2 which together form a spiral.
- the information carrier 1 carries an information file, which is represented as a hatched area.
- R ⁇ , OC B ) and (R E , OC E ) are, respectively, the starting position and the end position of the file.
- the dashed line 6' indicates the range over which the scanning point 6 can be moved.
- the information carrier should perform 0.75 revolution before the starting position (R B , CX B ) of the file to be read or written reaches the range 6'. in the case of a speed of 23 revolutions/second this corresponds to a rotational latency time of 32 ms.
- the apparatus in accordance with the invention now provides a reduction of the rotational latency time in that during reading and/or writing of a continuous file the information carrier 1 is scanned in accordance with a scanning mode in which the scanning point is moved both from one track to another track in a first radial direction and from one track to another track in an opposite second radial direction.
- the scanning point 6 jumps from a track to a more inward track and from a track to a more outward track for every revolution during reading and/or writing.
- the scanning point 6 the follows the path a-1 with respect to the information carrier 1.
- Figure 3B shows the relationship between the radial coordinate (R) of the scanning point 6 and the angle ( ⁇ ) traversed by the information carrier 1 in the case of the method in accordance with the invention.
- the vertical axis represents the radial position R of the scanning point 6 with respect to the axis 3, the unit of the radial coordinate being the track pitch.
- the horizontal axis represents the angle ⁇ traversed by the information carrier from the beginning of the path.
- the unit of the angle ⁇ is one revolution of the information carrier 1.
- the path begins at a radial coordinate R ⁇ + 0.25.
- the scanning point 6 now has a radial position a which coincides with a track 2 containing information of the file to be read.
- the scanning point 6 is moved in a radial direction R at a speed proportional to the angular velocity with which the information carrier 1 is rotated so that the scanning point 6 follows the track 2.
- the scanning point 6 jumps from a position b having a radial coordinate R B+ ⁇ to a position c having a radial coordinate R ⁇ .
- the scanning point 6 now follows the track 2 from the starting position for 0.25 revolutions of the information carrier 1, the value of the radial position R increasing proportionally to the angle ⁇ until the angle has become equal to 0 and then jumps from a position d having a radial coordinate R ⁇ + 0.25 to a position e having a radial coordinate R B + 1.25.
- the scanning point 6 moves along the path e-f-g-h-i in the same was as along the path a-b-c-d-e during the first revolution.
- the scanning point 6 has reached a position i having a radial coordinate R ⁇ +2.25.
- the latency time corresponds to the duration of 0.75 revolution.
- the latency time in this case corresponds to the duration of 0.25 revolution.
- the information carrier 1 also rotates during the jump to another track and initialization of means for processing a signal to be read or for generating a signal to be written may take time.
- Figure 3D represents the orientation of the information carrier 1 with respect to the transducer 5 at the instant that the read or write command is given.
- the path m-t followed by the scanning point 6 on the information carrier 1 is shown as a broken line.
- the angles corresponding to the points of the path m-t are given in parentheses. It is assumed that during each jump and the subsequent initialization the information carrier 1 traverses an angle ⁇ .
- the path begins at the innermost track allocated to the file to be read or written and situated in the range 6' of the scanning point.
- the scanning point 6 now follows this track from the point m to the point n.
- Figure 4A shows an information carrier 1 whose tracks 2 have been divided into four sectors SI - S4 each having a header 2A.
- the part of the information carrier 1 occupied by the file is shown as a hatched area.
- the sectors of mutually adjacent tracks have mutually the same tangential boundaries.
- Figure 4B illustrates the path followed by the scanning point. This path begins at a point u at the first track from the axis 3 of the information carrier portion assigned to the file and situated within the range 6' of the scanning point 6 at the instant at which the read or write command is received.
- the scanning point follows this track to the point u.
- the scanning point 6 jumps to a point w of the innermost track assigned to the file.
- This track contains the beginning of the file information.
- the scanning point follows this track to a point x.
- the scanning point subsequently jumps two tracks in an outward direction (from the point x a point y) and follows this track until 1 + ⁇ revolutions have been made.
- the scanning point 6 then jumps one track inward from a point z to a point aa and follows this to a point bb.
- Figure 5 graphically shows the relationship between the radial coordinate (R) of the scanning point and the angle ( ⁇ ) traversed by the information carrier shown in Figure 3 A for another method in accordance with the invention.
- the program steps 60 - 63 of the program shown in Figure 2 are carried out. This results in a scanning mode in which the scanning point moves one time in the first radial direction and subsequently moves more gradually in the second radial direction.
- the scanning point is positioned at a point i of the outermost track 2 of the information carrier in Figure 3 A which has been assigned to the file (program step 60).
- the scanning point 6 follows the path i-j along the track 2, a point j being the end position (R E , E ) of the file (program step 61). Subsequently, the scanning point moves from the point j on the track 2 followed so far to a point c on a more inward track (program step 62). The point c is also the starting position (R B , CX B ) of the file. After the scanning point 6 has reached the point c the continuous spiral tracks 2 are subsequently followed sequentially until the remainder of the file has been read or written (program step 63). The scanning point then moves gradually in the opposite second radial direction.
- Figures 6A and 6B illustrate this method for an information carrier 1 having mutually concentric separate tracks.
- the scanning point is positioned at a point cc on the outermost track which forms part of the file.
- this track is followed to a point dd.
- the scanning point is made to move from the point dd on the track 2 followed until then to a point ee situated on a more inward track.
- the program step 63 the file is read/written sequentially, the scanning point following the path ee-ff-gg-hh-ii-jj. The scanning point 6 is then moved more gradually in the opposite second radial direction.
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE60031492T DE60031492T2 (en) | 1999-04-23 | 2000-04-17 | DEVICE AND METHOD FOR TRYING A ROTATING INFORMATION CARRIER |
JP2000614444A JP4542713B2 (en) | 1999-04-23 | 2000-04-17 | Apparatus and method for scanning a rotating information carrier |
EP00926988A EP1090390B1 (en) | 1999-04-23 | 2000-04-17 | Apparatus and method for scanning a rotating information carrier |
HK01106952A HK1037772A1 (en) | 1999-04-23 | 2001-10-04 | Apparatus and method for scanning a rotating information carrier |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP99201284 | 1999-04-23 | ||
EP99201284.9 | 1999-04-23 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2000065581A1 true WO2000065581A1 (en) | 2000-11-02 |
Family
ID=8240138
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2000/003523 WO2000065581A1 (en) | 1999-04-23 | 2000-04-17 | Apparatus and method for scanning a rotating information carrier |
Country Status (9)
Country | Link |
---|---|
US (1) | US6680884B1 (en) |
EP (1) | EP1090390B1 (en) |
JP (1) | JP4542713B2 (en) |
CN (1) | CN1143278C (en) |
DE (1) | DE60031492T2 (en) |
HK (1) | HK1037772A1 (en) |
MY (1) | MY127902A (en) |
TW (1) | TW573295B (en) |
WO (1) | WO2000065581A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7463565B2 (en) * | 2005-08-30 | 2008-12-09 | Dt Soft Ltd. | Method of storing rotating media data in image file |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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US4677500A (en) * | 1984-02-08 | 1987-06-30 | U.S. Philips Corporation | System for playing back a film recorded as a video signal on a disc-shaped record carrier |
US5283875A (en) * | 1990-04-13 | 1994-02-01 | Digital Equipment Corporation | Method and apparatus for optimizing prefetch caching by reverse ordering of logical blocks |
US5864521A (en) * | 1995-03-03 | 1999-01-26 | Canon Kabushiki Kaisha | Information reproducing or recording apparatus provided with memory for storing data, and information reproducing or recording method using the same apparatus |
Family Cites Families (13)
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US4706133A (en) * | 1982-04-15 | 1987-11-10 | Discovision Associates | Method and apparatus for recovering information from a videodisc |
JPS5910168U (en) * | 1982-07-12 | 1984-01-23 | ソニー株式会社 | disc playback device |
JPS62208475A (en) * | 1986-03-07 | 1987-09-12 | Matsushita Electric Ind Co Ltd | Reproducing device |
JPH01267876A (en) * | 1988-04-19 | 1989-10-25 | Nec Corp | Magnetic disk device |
US5321676A (en) | 1991-12-10 | 1994-06-14 | U.S. Philips Corporation | Record carrier scanning apparatus wherein the scanning head is positioned without feedback and a predetermined range of fine positioning of the scanning point is maintained |
JPH0636482A (en) * | 1992-07-17 | 1994-02-10 | Victor Co Of Japan Ltd | Device for driving head |
JPH06267215A (en) * | 1993-03-16 | 1994-09-22 | Sony Corp | Head seeking mechanism for recording/reproducing device |
US5809201A (en) * | 1994-06-24 | 1998-09-15 | Mitsubishi Denki Kabushiki Kaisha | Specially formatted optical disk and method of playback |
US5570332A (en) | 1995-05-25 | 1996-10-29 | Seagate Technology, Inc. | Method for reducing rotational latency in a disc drive |
JP2778592B2 (en) * | 1996-08-30 | 1998-07-23 | 日本電気株式会社 | Optical disk scanning method and scanning device |
JPH10106169A (en) * | 1996-09-30 | 1998-04-24 | Toshiba Corp | Information reproducing device and information recording device |
JPH10302267A (en) * | 1997-04-25 | 1998-11-13 | Nec Corp | Optical disc recording medium and its recording method |
JP3547589B2 (en) * | 1997-06-27 | 2004-07-28 | パイオニア株式会社 | High-speed data playback method |
-
2000
- 2000-03-04 TW TW089103876A patent/TW573295B/en not_active IP Right Cessation
- 2000-04-17 JP JP2000614444A patent/JP4542713B2/en not_active Expired - Fee Related
- 2000-04-17 WO PCT/EP2000/003523 patent/WO2000065581A1/en active IP Right Grant
- 2000-04-17 CN CNB008011869A patent/CN1143278C/en not_active Expired - Fee Related
- 2000-04-17 DE DE60031492T patent/DE60031492T2/en not_active Expired - Lifetime
- 2000-04-17 EP EP00926988A patent/EP1090390B1/en not_active Expired - Lifetime
- 2000-04-20 MY MYPI20001682A patent/MY127902A/en unknown
- 2000-04-20 US US09/553,606 patent/US6680884B1/en not_active Expired - Fee Related
-
2001
- 2001-10-04 HK HK01106952A patent/HK1037772A1/en not_active IP Right Cessation
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4677500A (en) * | 1984-02-08 | 1987-06-30 | U.S. Philips Corporation | System for playing back a film recorded as a video signal on a disc-shaped record carrier |
US5283875A (en) * | 1990-04-13 | 1994-02-01 | Digital Equipment Corporation | Method and apparatus for optimizing prefetch caching by reverse ordering of logical blocks |
US5864521A (en) * | 1995-03-03 | 1999-01-26 | Canon Kabushiki Kaisha | Information reproducing or recording apparatus provided with memory for storing data, and information reproducing or recording method using the same apparatus |
Also Published As
Publication number | Publication date |
---|---|
DE60031492D1 (en) | 2006-12-07 |
DE60031492T2 (en) | 2007-06-28 |
TW573295B (en) | 2004-01-21 |
CN1315036A (en) | 2001-09-26 |
EP1090390A1 (en) | 2001-04-11 |
HK1037772A1 (en) | 2002-02-15 |
MY127902A (en) | 2006-12-29 |
JP2002543546A (en) | 2002-12-17 |
US6680884B1 (en) | 2004-01-20 |
JP4542713B2 (en) | 2010-09-15 |
EP1090390B1 (en) | 2006-10-25 |
CN1143278C (en) | 2004-03-24 |
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