In a DVD-R, lands 1 and grooves 2 are alternately formed in a spiral configuration; the lands 1 form projecting parts, and the grooves 2 form recessed parts 2. Recorded information is written into the grooves 2, while land pre-pits 3 are formed in some portions of the lands 1. The land pre-pits 3 form recessed parts, and the respective land pre-pits 3 cover the entire width of the corresponding land 1 as shown in the figures. These land pre-pits 3 are arranged so that a>b>0.5.times.a, where a is the maximum length of the land pre-pits, and b is the minimum length (ordinarily, the minimum length is the shorter of the lengths b1 and b2 of the land pre-pits in the circumferential edge portions of the lands (i.e., the boundary portions with the grooves)). Furthermore, the value of a is set at 0.2 .mu.m to 0.4 .mu.m.

 
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