RUN LENGTH CODE ERROR CORRECTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an RLL(run length limited) error correcting device which can increase the correcting number of errors while reducing erroneous correction. SOLUTION: An NRZ-1 converting section 61 converts NRZ (nonreturn- to-zero) modulated digital data into NRZ-1 modulated ones. An inhibit run length/inhibit pattern detecting section 21 detects an inhibit run length which is smaller than the lower limit value set by the run length coding method by one and a first inhibit run length which is positioned immediately before the inhibit run length and larger than the lower limit value from a bit pattern contained in the converted digital data. A run length/pattern converting section 22 expands the detected inhibit run length to the lower limit value by shortening the detected first run length by one. An error correcting section 64 executes error correction on the error-corrected digital data based on an error correcting code contained in the digital data.