Laser drive integrated circuit and optical disk apparatus using the same

• US 6,483,791 B1
• Filed: 01/29/1999
• Issued: 11/19/2002
• Est. Priority Date: 02/02/1998
• Status: Expired due to Term

• Current Assignee: Hitachi Consumer Electronics Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Kando, Hidehiko, Asada, Akihiro, Tanaka, Yasuhito, Kurebayashi, Masaaki, Kaku, Toshimitsu, Hoshino, Takashi, Ohnuki, Hideo
• Primary Examiner(s): Young, W. R.
• Assistant Examiner(s): CHU, KIM KWOK
• Application Number:
  US09/239,516
• Time in Patent Office: 1,390 Days
• Field of Search: 369/116, 369/13, 369/124.14, 369/112.04, 369/44.29, 369/112.17, 369/44.23, 369/44.37, 369/53.2, 369/13.54, 369/47.53, 369/47.5, 369/59.11
• US Class Current: 369/59.11
• CPC Class Codes: G11B 2007/0006 adapted for scanning different types of carrier, e.g. CD & DVD
• CPC Class Codes: G11B 7/0062 Overwriting strategies, e.g. recording pulse sequences with erasing level used for phase-change media
• CPC Class Codes: G11B 7/126 Circuits, methods or arrangements for laser control or stabilisation

Abstract

A laser drive integrated circuit and an optical disk apparatus using the laser drive integrated circuit for forming high-density marks. The optical disk apparatus has a drive waveform information storage unit for storing at least one information of the drive waveform for driving a laser diode in response to a binary recording signal recorded in a recording medium and a drive waveform decoder for decoding the drive waveform based on the information stored in the drive waveform information storage unit. The recording strategy can be changed in accordance with the variations and fluctuations of recording media or the characteristics of the recording media, while at the same time reducing the number of signal lines of flexible wiring and alleviating the effect of the signal distortion.

Claims

1. An optical disk apparatus comprising:

second drive waveform information storage means including a plurality of tables for segmenting at least a portion of a drive waveform corresponding to a mark for driving a laser diode into at least two segmented temporal portions and storing at least one drive waveform information for each of the segmented temporal portions of the drive waveform in each of the tables;

first drive waveform information storage means for storing a table address information for selecting the drive waveform information stored in each of the tables;

a decoder for decoding the drive waveform based on the drive waveform information stored in the second drive waveform information storage means;

an addressing generator for selecting the table address information stored in the first drive waveform information storage means based on a binary recording signal to be recorded in a recording medium; and

a controller for causing the drive waveform information to be stored in the second drive waveform information storage means and causing the table address information to be stored in the first drive waveform information storage means.

2. An optical disk apparatus according to claim 1, wherein the addressing generator selects the table address information stored in the first drive waveform information storage means based on a mark length and an adjacent space length of the binary recording signal.

3. An optical disk apparatus according to claim 1, wherein the controller supplies the drive waveform information to be stored in the second drive waveform information storage means to the second drive waveform information storage means together with an address for storing the drive waveform information, and supplies the table address information to be stored in the first drive waveform information storage means to the first drive waveform information storage means together with an address for storing the table address information.

4. An optical disk apparatus according to claim 1, wherein the second drive waveform information storage means stores the drive waveform information as drive waveform information described by two types of packets of drive waveform information, the two type of packets including

a first type of packet (L, RL) including

a level L of the drive waveform during a time period (T/2) which is a minimum time period after which a level of the drive waveform is permitted to change, the level of the drive waveform representing a recording power of the laser diode, and

a number RL of repetitions of the level L in units of the time period (T/2), and

a second type of packet (L1, L2) including

a level L1 of the drive waveform during a time period (T/2), and

a level L2 of the drive waveform during a time period (T/2) succeeding the time period (T/2) during which the level of the drive waveform is L1; and

wherein the decoder decodes the drive waveform in units of packets, and replaces the number RL of the first type of packet with a value calculated based on a mark length and a space length detected from the binary recording signal.

5. An optical disk apparatus according to claim 1, further comprising detecting means for detecting a type of a disk, the detecting means including a controller having a function of storing drive waveform information corresponding to the detected disk type in at least the second drive waveform information storage means.

6. An optical disk apparatus according to claim 1, further comprising detecting means for detecting recording and reproduction characteristics of a disk, the detecting means including a controller having a function of storing drive waveform information based on the detected recording and reproduction characteristics in at least the second drive waveform information storage means.

7. An optical disk apparatus according to claim 1, wherein the second drive waveform information storage means stores the drive waveform information as drive waveform information described by a series of sets of drive waveform information, each of the sets including

timing information CP of a level change point at which a level L of the drive waveform changes, the level L representing a recording power of the laser diode, and

the level L of the drive waveform after the level change point.

8. An optical disk apparatus according to claim 1, wherein the second drive waveform information storage means stores the drive waveform information as drive waveform information described by a series of at least a packet of drive waveform information expressed as P={(CP1, L1) . . . (CPn, Ln)} (n:

1 or more), the packet including at least a set of drive waveform information, the set including

timing information CP of a level change point at which a level L of the drive waveform changes, the level L representing a recording power of the laser diode, and

the level L of the drive waveform after the level change point.

9. A laser drive integrated circuit comprising:

second drive waveform information storage means including a plurality of tables for segmenting at least a portion of a drive waveform corresponding to a mark for driving a laser diode into at least two segmented temporal portions and storing at least one drive waveform information for each of the segmented temporal portions of the drive waveform in each of the tables, the drive waveform information being supplied from an external source;

first drive waveform information storage means for storing a table address information for selecting the drive waveform information stored in each of the tables;

a decoder for decoding the drive waveform based on the drive waveform information stored in the second drive waveform information storage means;

an addressing generator for selecting the table address information stored in the first drive waveform information storage means based on a binary recording signal to be recorded in a recording medium; and

a memory controller for causing the drive waveform information supplied from the external source to be stored in the second drive waveform information storage means and causing the table address information to be stored in the first drive waveform information storage means.

10. An optical disk apparatus comprising:

a laser drive integrated circuit including

second drive waveform information storage means including a plurality of tables for segmenting at least a portion of a drive waveform corresponding to a mark for driving a laser diode into at least two segmented temporal portions and storing at least one drive waveform information for each of the segmented temporal portions of the drive waveform in each of the tables, the drive waveform information being supplied from an external source external to the laser drive integrated circuit, and

decoding means for decoding the drive waveform based on the drive waveform information stored in the second drive waveform information storage means;

first drive waveform information storage means for storing a table address information for selecting the drive waveform information stored in each of the tables;

an addressing generator for selecting the table address information stored in the first drive waveform information storage means based on a binary recording signal to be recorded in a recording medium; and

a controller for causing the drive waveform information supplied from the external source external to the laser drive integrated circuit to be stored in the second drive waveform information storage means and causing the table address information to be stored in the first drive waveform information storage means.

11. An optical disk apparatus according to claim 10, wherein the controller supplies the drive waveform information to be stored in the second drive waveform information storage means to the second drive waveform information storing means together with an address for storing the drive waveform information.

12. An optical disk apparatus comprising:

drive waveform information storage means for storing at least one information of a drive waveform for driving a laser diode in accordance with a binary recording signal to be recorded in a recording medium;

decoding means for decoding the drive waveform based on the drive waveform information stored in the drive waveform information storage means;

an addressing generator for selecting the drive waveform information stored in the drive waveform information storage means based on the binary recording signal to be recorded in the recording medium; and

a controller for causing the drive waveform information to be stored in the drive waveform information storage means;

wherein the addressing generator selects the drive waveform information stored in the drive waveform information storage means based on a mark length and an adjacent space length of the binary recording signal.

13. An optical disk apparatus comprising:

drive waveform information storage means for storing at least one information of a drive waveform for driving a laser diode in accordance with a binary recording signal to be recorded in a recording medium;

decoding means for decoding the drive waveform based on the drive waveform information stored in the drive waveform information storage means;

an addressing generator for selecting the drive waveform information stored in the drive waveform information storage means based on the binary recording signal to be recorded in the recording medium; and

a controller for causing the drive waveform information to be stored in the drive waveform information storage means;

wherein the drive waveform information storage means stores the drive waveform information as drive waveform information described based on

a level L of the drive waveform, the level L representing a recording power of the laser diode, and

a number RL of repetitions of the level L in units of a time period (T/2) which is a minimum time period after which the level L of the drive waveform is permitted to change.

14. An optical disk apparatus comprising:

drive waveform information storage means for storing at least one information of a drive waveform for driving a laser diode in accordance with a binary recording signal to be recorded in a recording medium;

decoding means for decoding the drive waveform based on the drive waveform information stored in the drive waveform information storage means;

an addressing generator for selecting the drive waveform information stored in the drive waveform information storage means based on the binary recording signal to be recorded in the recording medium; and

a controller for causing the drive waveform information to be stored in the drive waveform information storage means;

wherein the drive waveform information storage means stores the drive waveform information as drive waveform information described by a series of packets of drive waveform information {(L1n, L2n, RLn), n;

0 to n}, each of the packets including

a level L1 of the drive waveform during a time period (T/2) which is a minimum time period after which a level of the drive waveform is permitted to change, the level of the drive waveform representing a recording power of the laser diode,

a level L2 of the drive waveform during a time period (T/2) succeeding the time period (T/2) during which the level of the drive waveform is L1, and

a number RL of repetitions of a set of the time period (T/2) during which the level of the drive waveform is L1 and the succeeding time period during which the level of the drive waveform is L2.

15. An optical disk apparatus according to claim 14 wherein the decoding means decodes the drive waveform in units of packets, and replaces the number RL of a predetermined packet with a value calculated based on a mark length or a space length detected from the binary recording signal.

16. A laser drive integrated circuit comprising:

drive waveform information storage means for storing at least one information of a drive waveform for driving a laser diode in accordance with a binary recording signal to be recorded in a recording medium, the drive waveform information being supplied from an external source;

a decoder for decoding the drive waveform based on the drive waveform information stored in the drive waveform information storage means;

an addressing generator for selecting the drive waveform information stored in the drive waveform information storage means based on the binary recording signal to be recorded in the recording medium; and

a memory controller for causing the drive waveform information supplied from the external source to be stored in the drive waveform information storage means;

wherein the laser drive integrated circuit is mounted on an optical pickup unit including a laser diode.

17. An optical disk apparatus comprising:

drive waveform information storage means for storing at least one information of a drive waveform for driving a laser diode in accordance with a binary recording signal to be recorded in a recording medium;

decoding means for decoding the drive waveform based on the drive waveform information stored in the drive waveform information storage means;

an addressing generator for selecting the drive waveform information stored in the drive waveform information storage means based on the binary recording signal to be recorded in the recording medium; and

a controller for causing the drive waveform information to be stored in the drive waveform information storage means;

wherein the drive waveform information storage means stores the drive waveform information as drive waveform information described by a series of sets of drive waveform information, each of the sets including

timing information CP of a level change point at which a level L of the drive waveform changes, the level L representing a recording power of the laser diode, and

the level L of the drive waveform after the level change point.

18. An optical disk apparatus according to claim 17, wherein the level L is at least a variable @L indicating the level L;

and

wherein the drive waveform information storage means stores the drive waveform information as drive waveform information described by a series of sets of the variable @L and a variable value table corresponding to each variable.

19. An optical disk apparatus according to claim 18 wherein the addressing generator includes at least one selectable table addressing generator for the variable value table.

20. An optical disk apparatus according to claim 17, wherein the decoder includes:

a change point timing generator for generating a level change point timing corresponding to the timing information CP; and

a level generator for generating a level corresponding to the level L of the drive waveform after the level change point.

21. An optical disk apparatus comprising:

drive waveform information storage means for storing at least one information of a drive waveform for driving a laser diode in accordance with a binary recording signal to be recorded in a recording medium;

decoding means for decoding the drive waveform based on the drive waveform information stored in the drive waveform information storage means;

an addressing generator for selecting the drive waveform information stored in the drive waveform information storage means based on the binary recording signal to be recorded in the recording medium; and

a controller for causing the drive waveform information to be stored in the drive waveform information storage means;

wherein the drive waveform information storage means stores the drive waveform information as drive waveform information described by a series of at least a packet of drive waveform information expressed as P={(CP1, L1) . . . (CPn, Ln)} (n;

1 or more), the packet including at least a set of drive waveform information, the set including

timing information CP of a level change point at which a level L of the drive waveform changes, the level L representing a recording power of the laser diode, and

the level L of the drive waveform after the level change point.