Method and apparatus for skew compensation in an optical reader

摘要

A method and apparatus for skew compensation in an optical reader is described. The method provides for calculating the amount of skew between the read scan line used to read the data and the recording path line used when the data was written on the recording media. By determining the position of each end of the scan line by counting delimiter marks along the two edges of the data being read, the skew can be calculated by determining the difference in delimiter counts. The data is divided into bands along the direction of scan within which the skew will not cause trouble misreadings at the extreme bits of the scan line within a band. The data is scanned multiple times during the transition of the data strip so that at least one good read of each data band in the data strip will occur.