To provide a stamper which prepares an optical recording medium which comprehensively satisfies various kinds of parameters of an LPP signal, a jitter, a PI error, etc. in a plane.

In the stamper having at least wobble grooves and land prepits formed on its surface, land prepits (LPP) 20 are constituted of a meandering part being a part of a wobble groove. In terms of the plurality of wobble grooves formed in the stamper, when comparing lengths Lw in a direction along the wobble grooves of the land prepits 20, the Lw become longer from the inner circumferential section to the outer circumferential section of the stamper (table 1 (not shown)).

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