Method for managing defect on optical disk and device therefor

摘要: PROBLEM TO BE SOLVED: To ensure a data by performing alternate processing on an after- defective sector causing read retrial at the time of executing command and based recovered in midst this hence to prevent speed from lowering due also reliability deteriorating upon access next afterward. SOLUTION: The is performed erasing execution part 21, writing 22 verifying 23 range, subjected ensured normality checking 24, then original address are added SDL, etc., defect list register 25 finish processing. Then, when cannot be obtained address, new object calculated again calculating 20, above procedure repeated until can confirmed.