WO2005114661A1 - Optical disc drive for writing on blank recordable or rewritable media - Google Patents

Optical disc drive for writing on blank recordable or rewritable media Download PDF

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Publication number
WO2005114661A1
WO2005114661A1 PCT/IB2005/051521 IB2005051521W WO2005114661A1 WO 2005114661 A1 WO2005114661 A1 WO 2005114661A1 IB 2005051521 W IB2005051521 W IB 2005051521W WO 2005114661 A1 WO2005114661 A1 WO 2005114661A1
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WO
WIPO (PCT)
Prior art keywords
optical disc
data
disc drive
parameter setting
writing
Prior art date
Application number
PCT/IB2005/051521
Other languages
French (fr)
Inventor
Johannes L. Bakx
Original Assignee
Koninklijke Philips Electronics N.V.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Koninklijke Philips Electronics N.V. filed Critical Koninklijke Philips Electronics N.V.
Publication of WO2005114661A1 publication Critical patent/WO2005114661A1/en

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Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
    • G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
    • G11B7/126—Circuits, methods or arrangements for laser control or stabilisation
    • G11B7/1267—Power calibration
    • 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
    • G11B7/007—Arrangement of the information on the record carrier, e.g. form of tracks, actual track shape, e.g. wobbled, or cross-section, e.g. v-shaped; Sequential information structures, e.g. sectoring or header formats within a track
    • G11B7/00736—Auxiliary data, e.g. lead-in, lead-out, Power Calibration Area [PCA], Burst Cutting Area [BCA], control information

Definitions

  • Optical disc drive for writing on blank recordable or rewritable media
  • the present invention relates to an optical disc drive for writing data on recordable and/or rewritable optical discs.
  • the disc drive according to the invention is particularly adapted to write on blank media.
  • US 2002/0122359 discloses an optical disc drive capable of determining an optimum radiation power of laser for recording data in accordance with an asymmetry value or amplitude of a read signal. Pre-test data is recorded in a trial write area provided on the optical disc with the laser power kept constant while the focus offset is changed. An asymmetry value of a read signal of the pre-test data is minimized. The optimum power of the laser is determined in accordance with the asymmetry value.
  • it is necessary to write test data in the trial write area regardless of whether or not data is already present on the disc.
  • a new set of test data needs to be recorded. This is a disadvantage, because the area available for test writing is very limited on certain types of discs.
  • an optical disc drive which is capable of determining optimum parameter settings in order to write data on the disc using these optimum parameter settings, while avoiding the need for writing test data in the test area each time data is to be written on the disc.
  • an optical disc drive comprising: - means for detecting whether data is already present on an optical disc, means for writing test data in a test area of said optical disc, using a default setting of one or more parameters, in case no data is present, - means for finding an optimum parameter setting on the basis of said test data, - means for writing data on the optical disc using the optimum parameter setting.
  • the above and other objects are fulfilled by providing a method for writing data on an optical disc, the method comprising the steps of: - detecting whether data is already present on the optical disc, in case no data is present, writing test data in a test area of the optical disc, using a default setting of one or more parameters, - finding an optimum parameter setting on the basis of said test data, - writing data on the optical disc using the optimum parameter setting.
  • the above and other objects are fulfilled by providing a computer program adapted to control the method steps of the method according to the second aspect when run on a computer.
  • the first, second and third aspects of the present invention may each be combined with any of the other aspects.
  • the optical disc drive comprises means for detecting whether data is already present on the disc, and due to the fact that test data is only written in the test area if no data is already present, it is avoided that unnecessary test data is written in the test area.
  • test data it is only necessary to write test data in the test area once, i.e. the first time data is to be written on the optical disc.
  • the data already present on the disc can be used for finding the optimum parameter setting.
  • the test data needed to be written in the test area is kept at an absolute minimum. Due to the limited test area available on certain kinds of discs as described above, this is a great advantage.
  • the optical disc drive is capable of writing data onto blank media with optimum parameter settings, thereby enhancing the write performance.
  • the optical disc drive may further comprise means for applying an optimum power control (OPC) procedure.
  • OPC optimum power control
  • the means for writing test data may use the power found by applying the OPC procedure with the default parameter setting, when writing the test data.
  • the test data is written with a writing power which is optimum with respect to the default parameter setting.
  • the means for writing data on the optical disc may use the power found by applying the OPC procedure with the found optimum parameter setting, when writing the data on the optical disc.
  • the actual data is written with not only an optimum parameter setting, but also with a writing power that is optimum with respect to the optimum parameter setting.
  • the means for finding an optimum parameter setting employs a jitter-based calibration method.
  • a calibration method involves readout of a written region with varying parameter values, and measuring the jitter for each parameter value. The value for which the jitter is at a minimum is the optimum value.
  • the means for finding an optimum parameter setting may employ an asymmetry-based calibration method and or a Bit-Error-Rate-based calibration method.
  • the means for finding an optimum parameter setting may further be adapted to find an optimum parameter setting on the basis of data which is already present on the optical disc in case such data is present.
  • the optical disc drive may further comprise means for storing the found optimum parameter setting.
  • the storing means may be, e.g., an eeprom.
  • the found optimum parameter setting may be stored on the disc itself. Since the setting is at least partly disc dependent (and partly drive dependent), this may be an advantage since the setting is stored on the disc to which it belongs, thereby making disc dependent information readily available at a later time.
  • the means for writing test data may be adapted to use a stored optimum parameter setting as a default parameter setting for a subsequent optical disc.
  • the drive will use a previously found optimum setting when the next disc is inserted in the drive.
  • the stored setting may be used without applying the procedure described above.
  • the default setting may also be used for writing test data in the test area, even in case data is already present on the subsequent disc. If an error has occurred which prevents proper calibration on the basis of this data, e.g. due to media contamination, it will be necessary to write test data in the test area even though data is already present.
  • the one or more parameters may advantageously comprise focus, tilt, such as radial tilt and/or tangential tilt, spherical aberration (which is especially useful for blue laser systems), and/or any other suitable kind of parameters.
  • the optical disc is preferably a recordable or a rewritable disc, e.g. CD-R, CD- RW, DVD ⁇ R, DVD+RW and/or any other suitable kind of disc.
  • FIG. 1 is a flow chart illustrating the procedure of one embodiment of the present invention.
  • Fig. 1 illustrates a procedure for writing data on an optical disc with an optimum focus offset setting and an optimum tilt setting.
  • OPC procedure based on asymmetry is performed using a default focus setting.
  • it is investigated whether or not the focus offset is already optimum, i.e. whether or not the focus has already been calibrated. If this is the case, the procedure goes straight to step 5 (see below). In case the focus offset is not already optimum, two tracks are written in the
  • the focus offset in the OPC area is optimized at 4 using, e.g., a jitter-based calibration.
  • the tilt is already optimum, i.e. whether or not this parameter has already been calibrated. If this is the case, the procedure goes straight on to step 9 (see below).
  • the procedure proceeds to step 8. If not, two tracks are written at 7, using the power found by the OPC procedure at 1, and the procedure subsequently proceeds to step 8.
  • the optimum tilt setting is found with a jitter-based calibration procedure using the test data in the OPC area.
  • an OPC procedure based on jitter (and optionally on asymmetry) is performed using the optimized settings, in order to find the optimum writing power.
  • the found writing power is subsequently used when data is written on the disc.

Abstract

Optical disc drive for writing data on a recordable and/or rewritable optical disc (such as a CD+R, CD+RW, DVD±R or DVD±RW). The optical disc drive writes test data in test area in case no data is already present on the disc. Optimum parameter settings (such as focus, tilt or spherical aberration) are found by using, e.g., a jitter-based calibration procedure. Data is written on the disc using the optimum parameter setting thus found. Preferably the optimum writing power is also found using an optimum power control (OPC) procedure. In case data is already present on the disc this data is used for the optimizing procedure. Thereby writing test data in the test area if other data is already present is avoided. The disc drive is particularly adapted to write on blank media.

Description

Optical disc drive for writing on blank recordable or rewritable media
FIELD OF THE INVENTION The present invention relates to an optical disc drive for writing data on recordable and/or rewritable optical discs. The disc drive according to the invention is particularly adapted to write on blank media.
BACKGROUND OF THE INVENTION US 2002/0122359 discloses an optical disc drive capable of determining an optimum radiation power of laser for recording data in accordance with an asymmetry value or amplitude of a read signal. Pre-test data is recorded in a trial write area provided on the optical disc with the laser power kept constant while the focus offset is changed. An asymmetry value of a read signal of the pre-test data is minimized. The optimum power of the laser is determined in accordance with the asymmetry value. Thus, in order to find the optimum focus setting using the optical disc drive of US 2002/0122359, it is necessary to write test data in the trial write area regardless of whether or not data is already present on the disc. Thus, every time new data is to be recorded on a specific disc, a new set of test data needs to be recorded. This is a disadvantage, because the area available for test writing is very limited on certain types of discs.
SUMMARY OF THE INVENTION Thus, it is an object of the present invention to provide an optical disc drive, which is capable of determining optimum parameter settings in order to write data on the disc using these optimum parameter settings, while avoiding the need for writing test data in the test area each time data is to be written on the disc. According to a first aspect of the present invention, the above and other objects are fulfilled by providing an optical disc drive comprising: - means for detecting whether data is already present on an optical disc, means for writing test data in a test area of said optical disc, using a default setting of one or more parameters, in case no data is present, - means for finding an optimum parameter setting on the basis of said test data, - means for writing data on the optical disc using the optimum parameter setting. According to a second aspect of the present invention, the above and other objects are fulfilled by providing a method for writing data on an optical disc, the method comprising the steps of: - detecting whether data is already present on the optical disc, in case no data is present, writing test data in a test area of the optical disc, using a default setting of one or more parameters, - finding an optimum parameter setting on the basis of said test data, - writing data on the optical disc using the optimum parameter setting. According to a third aspect of the present invention, the above and other objects are fulfilled by providing a computer program adapted to control the method steps of the method according to the second aspect when run on a computer. The first, second and third aspects of the present invention may each be combined with any of the other aspects. Due to the fact that the optical disc drive comprises means for detecting whether data is already present on the disc, and due to the fact that test data is only written in the test area if no data is already present, it is avoided that unnecessary test data is written in the test area. Thus, in principle, it is only necessary to write test data in the test area once, i.e. the first time data is to be written on the optical disc. For any subsequent data to be written on the disc, the data already present on the disc can be used for finding the optimum parameter setting. Thereby the test data needed to be written in the test area is kept at an absolute minimum. Due to the limited test area available on certain kinds of discs as described above, this is a great advantage. Thereby the optical disc drive according to the present invention is capable of writing data onto blank media with optimum parameter settings, thereby enhancing the write performance. The optical disc drive may further comprise means for applying an optimum power control (OPC) procedure. In this case, the means for writing test data may use the power found by applying the OPC procedure with the default parameter setting, when writing the test data. Thereby the test data is written with a writing power which is optimum with respect to the default parameter setting. Alternatively or additionally, the means for writing data on the optical disc may use the power found by applying the OPC procedure with the found optimum parameter setting, when writing the data on the optical disc. In this case the actual data is written with not only an optimum parameter setting, but also with a writing power that is optimum with respect to the optimum parameter setting. Thereby an optimum write performance is ensured for all data written on the disc. In one embodiment the means for finding an optimum parameter setting employs a jitter-based calibration method. Such a calibration method involves readout of a written region with varying parameter values, and measuring the jitter for each parameter value. The value for which the jitter is at a minimum is the optimum value. Alternatively or additionally, the means for finding an optimum parameter setting may employ an asymmetry-based calibration method and or a Bit-Error-Rate-based calibration method. The means for finding an optimum parameter setting may further be adapted to find an optimum parameter setting on the basis of data which is already present on the optical disc in case such data is present. Thus, in case data is already present on the disc, this data is used for finding an optimum parameter setting. Thus, it is not necessary to write test data in the test area in order to find the optimum parameter setting. The optical disc drive may further comprise means for storing the found optimum parameter setting. The storing means may be, e.g., an eeprom. Alternatively or additionally, the found optimum parameter setting may be stored on the disc itself. Since the setting is at least partly disc dependent (and partly drive dependent), this may be an advantage since the setting is stored on the disc to which it belongs, thereby making disc dependent information readily available at a later time. The means for writing test data may be adapted to use a stored optimum parameter setting as a default parameter setting for a subsequent optical disc. In this case the drive will use a previously found optimum setting when the next disc is inserted in the drive. In case the parameter setting is stored on the disc itself, the stored setting may be used without applying the procedure described above. The default setting may also be used for writing test data in the test area, even in case data is already present on the subsequent disc. If an error has occurred which prevents proper calibration on the basis of this data, e.g. due to media contamination, it will be necessary to write test data in the test area even though data is already present. The one or more parameters may advantageously comprise focus, tilt, such as radial tilt and/or tangential tilt, spherical aberration (which is especially useful for blue laser systems), and/or any other suitable kind of parameters. The optical disc is preferably a recordable or a rewritable disc, e.g. CD-R, CD- RW, DVD±R, DVD+RW and/or any other suitable kind of disc. These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment described hereinafter.
BRIEF DESCRIPTION OF THE DRAWING Fig. 1 is a flow chart illustrating the procedure of one embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS The flow chart of Fig. 1 illustrates a procedure for writing data on an optical disc with an optimum focus offset setting and an optimum tilt setting. At 1 an OPC procedure based on asymmetry is performed using a default focus setting. At 2 it is investigated whether or not the focus offset is already optimum, i.e. whether or not the focus has already been calibrated. If this is the case, the procedure goes straight to step 5 (see below). In case the focus offset is not already optimum, two tracks are written in the
OPC (test) area of the disc at 3, using the power found by the OPC procedure at 1. Based on these tracks, the focus offset in the OPC area is optimized at 4 using, e.g., a jitter-based calibration. At 5 it is investigated whether or not the tilt is already optimum, i.e. whether or not this parameter has already been calibrated. If this is the case, the procedure goes straight on to step 9 (see below). In case the tilt is not already optimum, it is investigated at 6 whether or not test tracks have already been written in the OPC area. If this is the case, the procedure proceeds to step 8. If not, two tracks are written at 7, using the power found by the OPC procedure at 1, and the procedure subsequently proceeds to step 8. At 8 the optimum tilt setting is found with a jitter-based calibration procedure using the test data in the OPC area. At 9 an OPC procedure based on jitter (and optionally on asymmetry) is performed using the optimized settings, in order to find the optimum writing power. The found writing power is subsequently used when data is written on the disc. The procedure described above thus provides for (independent) focus offset and tilt optimization. Although the present invention has been described in connection with the preferred embodiment, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. In the claims, the term comprising does not exclude the presence of other elements or steps. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. Thus, references to "a" or "an" do not preclude a plurality. Furthermore, reference signs in the claims shall not be construed as limiting the scope.

Claims

CLAIMS:
1. An optical disc drive comprising:
- means for detecting whether data is already present on an optical disc,
- means for writing test data in a test area of said optical disc, using a default setting of one or more parameters, in case no data is present,
- means for finding an optimum parameter setting on the basis of said test data,
- means for writing data on the optical disc using the optimum parameter setting.
2. An optical disc drive according to claim 1, further comprising means for applying an optimum power control (OPC) procedure.
3. An optical disc drive according to claim 2, wherein the means for writing test data uses the power found by applying the OPC procedure with the default parameter setting, when writing the test data.
4. An optical disc drive according to claim 2, wherein the means for writing data on the optical disc uses the power found by applying the OPC procedure with the found optimum parameter setting, when writing the data on the optical disc.
5. An optical disc drive according to claim 1, wherein the means for finding an optimum parameter setting employs a jitter-based calibration method.
6. An optical disc drive according to claim 1, wherein the means for finding an optimum parameter setting employs an asymmetry-based calibration method.
7. An optical disc drive according to claim 1, wherein the means for finding an optimum parameter setting employs a Bit-Error-Rate-based calibration method.
8. An optical disc drive according to claim 1, wherein the means for finding an optimum parameter setting is further adapted to find an optimum parameter setting on the basis of data which is already present on the optical disc in case such data is present.
9. An optical disc drive according to claim 1, further comprising means for storing the found optimum parameter setting.
10. An optical disc drive according to claim 9, wherein the storing means is an eeprom.
11. An optical disc drive according to claim 9, wherein the means for writing test data is adapted to use a stored optimum parameter setting as a default parameter setting for a subsequent optical disc.
12. An optical disc drive according to claim 1, wherein the one or more parameters comprise focus.
13. An optical disc drive according to claim 1, wherein the one or more parameters comprise tilt.
14. An optical disc drive according to claim 13, wherein the one or more parameters comprise radial tilt.
15. An optical disc drive according to claim 13, wherein the one or more parameters comprise tangential tilt.
16. An optical disc drive according to claim 1, wherein the one or more parameters comprise spherical aberration.
17. An optical disc drive according to claim 1, wherein the optical disc is a recordable or a rewritable disc.
18. A method for writing data on an optical disc, the method comprising the steps of: - detecting whether data is already present on the optical disc,
- in case no data is present, writing (3, 7) test data in a test area of the optical disc, using a default setting of one or more parameters,
- finding (4, 8) an optimum parameter setting on the basis of said test data,
- writing data on the optical disc using the optimum parameter setting.
19. A computer program adapted to control the method steps of claim 18 when run on a computer.
PCT/IB2005/051521 2004-05-18 2005-05-10 Optical disc drive for writing on blank recordable or rewritable media WO2005114661A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP04102200 2004-05-18
EP04102200.5 2004-05-18

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006018770A3 (en) * 2004-08-13 2006-08-10 Koninkl Philips Electronics Nv Method and apparatus for determining optical disc recording parameters
WO2007072437A2 (en) 2005-12-21 2007-06-28 Koninklijke Philips Electronics N.V. A method of operating a data recording device
US7859964B2 (en) 2006-03-23 2010-12-28 Lg Electronics Inc. Method and apparatus of adjusting focusing servo in optical disc device
US8107338B2 (en) 2007-04-11 2012-01-31 Koninklijke Philips Electronics N.V. Power calibration in optical disc drives

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0442566A1 (en) * 1990-02-12 1991-08-21 Koninklijke Philips Electronics N.V. Information recording device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0442566A1 (en) * 1990-02-12 1991-08-21 Koninklijke Philips Electronics N.V. Information recording device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006018770A3 (en) * 2004-08-13 2006-08-10 Koninkl Philips Electronics Nv Method and apparatus for determining optical disc recording parameters
WO2007072437A2 (en) 2005-12-21 2007-06-28 Koninklijke Philips Electronics N.V. A method of operating a data recording device
WO2007072437A3 (en) * 2005-12-21 2007-10-11 Koninkl Philips Electronics Nv A method of operating a data recording device
US7859964B2 (en) 2006-03-23 2010-12-28 Lg Electronics Inc. Method and apparatus of adjusting focusing servo in optical disc device
US8107338B2 (en) 2007-04-11 2012-01-31 Koninklijke Philips Electronics N.V. Power calibration in optical disc drives

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