Claims
- 1. A method of calibrating a readback threshold for an optical storage disk, comprising the steps of:
- mounting an optical disk in an optical storage drive;
- seeking to a first predetermined sector known to have information written thereon;
- setting a preamplifier gain to a first level;
- reading the information from the first predetermined sector and obtaining a first data envelope having a first readback amplitude;
- setting the preamplifier gain to a second level;
- seeking to a second predetermined sector known to have information written thereon;
- reading the information from the second predetermined sector and obtaining a second data envelope having a second readback amplitude; and
- calculating a readback threshold from the first readback amplitude and the second readback amplitude.
- 2. The method of claim 1, wherein said calculating step comprises the step of calculating the readback threshold from the first and second readback amplitudes.
- 3. The method of claim 2, wherein:
- the first and second predetermined sectors are a first plurality and a second plurality of consecutive sectors, respectively;
- said step of obtaining the first data envelope comprises the step of obtaining a data envelope from each of the first plurality of sectors and averaging their readback amplitudes; and
- said step of obtaining the second data envelope comprises the step of obtaining a data envelope from each of the second plurality of sectors and averaging their readback amplitudes.
- 4. The method of claim 3, wherein:
- the first level of the preamplifier gain is a low level;
- the second level of the preamplifier gain is a high level; and
- said calculating step comprises the step of calculating the readback threshold according to the equation: (3L-H)/2, where L and H are the first and second readback amplitudes, respectively.
- 5. A method of calibrating a readback threshold for an optical storage disk, comprising the steps of:
- mounting an optical disk in an optical storage drive;
- seeking to a first predetermined sector known to have information written thereon;
- reading the information from the first predetermined sector and obtaining a first data envelope having a first readback amplitude;
- calculating a readback threshold from the first readback amplitude;
- determining whether the calculated readback threshold is within an acceptable range of readback thresholds; and
- if the calculated readback threshold is not within the acceptable range of readback thresholds:
- seeking to a second predetermined sector known to have information written thereon;
- reading the information from the second predetermined sector and obtaining a second data envelope having a second readback amplitude; and
- calculating a second readback threshold from the second readback amplitude and the first readback amplitude.
Parent Case Info
This Application is a divisional of application Ser. No. 8/197,525, filed Feb. 16, 1994, now U.S. Pat. No. 5,430,702.
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Divisions (1)
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Number |
Date |
Country |
Parent |
197525 |
Feb 1994 |
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