FLATNESS MEASURING DEVICE

PROBLEM TO BE SOLVED: To enlarge the measurable range and keep the region resolution in a flatness measuring device using a wavefront sensor of Shack-Hartman.SOLUTION: The flatness measuring device includes: a light source 1; light guiding means 2 for guiding primary light B1 to a measuring object W; a lens array 3 including a plurality of lenses arranged along a first direction and a second direction; and imaged shape changing means 6 for shielding the primary light B1 to make the imaged shapes that are formed in a two-dimensional region by the light beams passing through adjacent lenses along the first direction different from each other, and make the imaged shapes that are formed in the two-dimensional region by the light beams passing through adjacent lenses along the second direction different from each other. 【課題】シャック−ハルトマンの波面センサを用いた平面度測定装置において、測定可能範囲を拡大するとともに領域分解能を維持する。【解決手段】光源１と、一次光Ｂ１を測定対象Ｗに導く導光手段２と、複数のレンズが第１の方向及び第２の方向に沿って並べられているレンズアレイ３と、一次光Ｂ１を遮蔽して、第１の方向に沿って隣り合うレンズを通った光によって二次元領域に形成される結像形状を異なる形状とするとともに、第２の方向に沿って隣り合うレンズを通った光によって二次元領域に形成される結像形状を異なる形状とする結像形状変更手段６とを具備するようにした。【選択図】図３