Compensation for thermal effects in CD write strategy

Dynamic information storage or retrieval – Binary pulse train information signal – Binary signal processing for controlling recording light...

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C369S047500, C369S116000

Reexamination Certificate

active

06388970

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to compensation for thermal effects in mark and space lengths for compact disk write strategy.
BACKGROUND OF THE INVENTION
At present, analysis of thermal effects from adjacent marks and spaces, upon the lengths of marks written onto a compact disk (CD), requires use of special patterns and of special and complex equipment for such purposes. A CD-RW will manifest modest thermal effects, but a CD-R will manifest much greater thermal effects. Where a typical CD-R or CD-RW drive is used, it may be difficult or impossible to generate or analyze the special patterns needed. The present approaches may not allow account to be taken of variation of thermal effects with disk write speed and may require use of inflexible analytical models.
What is needed is another approach to analysis of thermal effects on lengths of marks written onto CD-R/RWs that does not require use of special patterns or complex equipment and that provides accurate statistical information on the extent of these thermal effects. Preferably, the approach should be flexible, should allow use of two or more methods to analyze these effects and should allow for variation of thermal effects with disk write speed. Preferably, the approach should provide this analysis in relatively short time for all of the mark and space patterns that can be reasonably expected to occur in CD-R/RW processing. Preferably, the approach should have a low associated disk error rate and should permit a statistical analysis of the data used to compensate for these thermal effects.
SUMMARY OF THE INVENTION
These needs are met by the invention, which provides a method of measurement and analysis of thermal effects for each of the permutations of adjacent marks and spaces that occur in writing to a CD-R or CD-R/RW medium. Thermal effects associated with each of Q combinations of lengths of adjacent marks and spaces (“characters”) are measured, compared with reference data, and analyzed and presented in a format that can be directly used by a CD-R/RW processing device to automatically compensate for change in length of a mark due to the lengths of the adjacent mark and space characters. Here, Q is a measure of the number of legitimate combinations of lengths of adjacent characters associated with a particular mark length. Statistical data are developed from the analysis and are used to estimate expected CD error rates after compensation for thermal effects is included. Variation of thermal effects with disk write speed is also determined.


REFERENCES:
patent: 5631887 (1997-05-01), Hurst, Jr.
patent: 5696747 (1997-12-01), Bartholomeusz
patent: 5742566 (1998-04-01), Imai
patent: 6188658 (2001-02-01), Saga et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Compensation for thermal effects in CD write strategy does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Compensation for thermal effects in CD write strategy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compensation for thermal effects in CD write strategy will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2894405

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.