Method for reading information or defect out of rotating disc
Patent
·
OSTI ID:5418388
In order to read out information recorded on a disc rotating at a constant angular velocity by means of a pick-up head movably arranged in a disc radius direction, a head position on the disc is detected to obtain a position signal representing a distance from a disc center to the pick-up head, and then a pulse signal having a frequency corresponding to the position signal thus obtained is generated. A detection signal supplied from the pick-up head and the pulse signal are supplied to an AND gate and pulses of the gated out pulse signal are counted by a counter. The number of the counted pulses represents correctly a length of the information recorded on the disc irrespective of position of the information on the disc.
- Assignee:
- Olympus Optical Co. Ltd. (Japan)
- Patent Number(s):
- US 4499572
- OSTI ID:
- 5418388
- Country of Publication:
- United States
- Language:
- English
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