Abstract: A test disk having defect patterns uniformly arranged in recording areas is produced by a production method including: producing a stamper having a plurality of data pits in accordance with test data signals recorded on the test disk; radiating laser light to the stamper by using a laser system so that a plurality of small patterns are produced at laser-light exposed portions along first lines on the stamper, to form interruptions, which interrupt the data pits on the stamper, in accordance with the small patterns; and performing injection molding with plastic material to produce a disk based on the stamper, so that the disk has interruptions corresponding to the interruptions of the stamper, and the interruptions of the disk are included in a recording layer of the disk.