Trial writing method and optical disk system using the same

• US 6,654,325 B1
• Filed: 11/29/2001
• Issued: 11/25/2003
• Est. Priority Date: 08/09/1999
• Status: Expired due to Fees

• Current Assignee: Hitachi Consumer Electronics Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Minemura, Hiroyuki, Tsuchinaga, Hiroyuki
• Primary Examiner(s): Edun, Muhammed
• Application Number:
  US09/914,427
• Time in Patent Office: 726 Days
• Field of Search: 369/47.1, 369/47.15, 369/47.28, 369/47.29, 369/47.48, 369/53.1, 369/53.11, 369/53.34, 369/59.1, 369/59.2, 369/60.01
• US Class Current: 369/47.28
• CPC Class Codes: G11B 7/0045 Recording G11B7/006, G11B7/0065 take precedence
• CPC Class Codes: G11B 7/00454 involving phase-change effects
• CPC Class Codes: G11B 7/006 Overwriting G11B7/0065 takes precedence
• CPC Class Codes: G11B 7/126 Circuits, methods or arrangements for laser control or stabilisation
• CPC Class Codes: G11B 7/1267 Power calibration

Abstract

A method of recording information on an information medium, especially on an optical recording medium with light. It has been hard to determine optimum power accurately due to the influence of the linearity and the mark length dependence on rewrite deterioration when a write parameter calibration on a phase change optical disk is performed by a conventional asymmetry method prior to information recording. According to the present invention, a single pattern or a random pattern is recorded on an information medium, and the difference between the clock and the data edge is detected using a reproduced signal. On the basis of this difference, the threshold power of the recording is determined and multiplied by a constant to optimize the recording power.

Claims

1. A write parameter calibration method, comprising:

a process of recording data patterns on an information medium while controlling a recording condition according to the recording data patterns;

a process of reading the data patterns recorded on said information medium to acquire a reproduced signal;

a process of generating a clock signal from said reproduced signal;

a process of comparing a phase difference between said reproduced signal and said clock signal with a given value and generating pulses according to a result of the comparison;

a process of classifying data patterns of said reproduced signal into respective pattern groups;

a process of classifying said pulses into said classified pattern groups;

a process of counting said classified pulses; and

a process of determining a recording condition according to said recording data pattern on the basis of a result of said counting

a process of detecting a phase difference between the reproduced signal and a reference signal and a clock signal generated from the reproduced signal;

a process of discriminating the phase difference for classification according to said data pattern; and

a process of determining the recording condition according to said discriminated phase difference.

2. The method according to claim 1,

wherein said information medium is a disk-type optical information recording medium;

wherein said reference signal is a clock signal generated from the reproduced signal; and

wherein said recording condition is power, a pulse width, or a position of an emitted laser beam.

3. An optical disk drive, which is an information device for recording and reproducing information on said information medium, at least comprising:

means for rotating said information medium;

means for condensing semiconductor laser beams into said information medium; and

laser driving means for modulating an output, a pulse width, or a position of said semiconductor laser according to recorded data,

wherein it has means for determining a condition for recording into said information medium using the write parameter calibration method according to claim 1.

4. The optical disk drive according to claim 3, further comprising:

means for recording said recording condition determined by said write parameter calibration method into a specific area of said information medium; and

means for reproducing said recording condition recorded on said information medium.

5. The method according to claim 1,

wherein said process of comparing said phase difference with a given value and generating pulses according to the comparison result is a process of generating pulses when said phase difference is greater than said given value.

6. A write parameter calibration method, comprising:

a process of recording data patterns on an information medium while controlling a recording condition according to said recording data patterns;

a process of reading the data patterns recorded on said information medium to acquire a reproduced signal;

a process of generating a clock signal from said reproduced signal;

a process of comparing a phase difference between said reproduced signal and said clock signal with a given value and generating pulses according to a result of the comparison;

a process of classifying data patterns of said reproduced signal into respective pattern groups;

a process of classifying said pulses into said classified pattern groups;

a process of counting said classified pulses; and

a process of measuring a number of marks or of spaces included in said reproduced signal;

a process of comparing the number of marks or of spaces included in said reproduced signal with a number of marks or of spaces included in said recorded data patterns; and

a process of determining a recording condition according to said recording data pattern on the basis of a result of said counting

a process of measuring the number of marks or of spaces included in the reproduced signal;

a process of comparing the number of marks or of spaces in the reproduced data with the number of marks or of spaces in the recorded data; and

a process of determining the recording condition according to a result of the comparison.