Reading from record medium in either an inverted or non-inverted

Details Reading from record medium in either an inverted or non-inverted Reading from record medium in either an inverted or non-inverted

1995-04-07

1996-10-22

Epps, Georgia Y.

Dynamic information storage or retrieval

Specific detail of information handling portion of system

Radiation beam modification of or by storage medium

369 32, 369 47, 369 54, 369 58, 3692752, G11B 700

Patent

active

055684653

ABSTRACT:
In a write-once read-many (WORM) optical disk device recorded unipolar pulse signals having a high lineal recorded densities are read back using an inverted analog signal processing channel that processes the read back signal after polarity inversion of the read back signal. Some fields in each sector of an optical disk are recorded at a specific maximal mark density pattern. Read back of such fields is signal processed using non-inverted read back analog signal processing, i.e. the read back unipolar pulse signal is processed without polarity inversion. In the non-inverted read back, automatic gain control of the read signal is turned off such that amplification of the read back signal is at a constant gain. Also during non-inverted read back, low read back signal amplitude results in degating the read back output. These signal processing techniques produce a pulse stream which can be further processed by a circuit which qualifies acceptable time intervals and a counter to robustly determine whether the field has been written. Digital signal processing provides signal detection with or without read back signal inversion while maintaining robust flag signal detection. Digital automatic gain control is effected to an acceptable range of signal amplitudes either continuously, on a sector basis, detected error basis or session basis.

REFERENCES:
patent: 4831611 (1989-05-01), Susaki et al.
patent: 5060218 (1991-10-01), Chiyomatsu
patent: 5161144 (1992-11-01), Takeuchi et al.
patent: 5202877 (1993-04-01), Yanagida
patent: 5283779 (1994-02-01), Otsuki
patent: 5309420 (1994-05-01), Jaquette et al.
patent: 5430702 (1995-07-01), Bish et al.
patent: 5432762 (1995-07-01), Kubo et al.

Affiliated with

Also associated with

Rating

Reading from record medium in either an inverted or non-inverted does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Reading from record medium in either an inverted or non-inverted, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reading from record medium in either an inverted or non-inverted will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2365014