| 摘要 |
<p>A two-dimensional position detecting method detects a two-dimensional position of an object which has a diffraction grating (33) provided thereon, and this diffraction grating comprises a first grating portion (33x) which extends in a first direction (X) and a second grating portion (33y) which extends in a second direction (Y) which is perpendicular to the first direction. The two-dimensional position detecting method scans the first grating portion of the diffraction grating in the second direction by a coherent light and detects by a photosensor (32) an mth order spectrum which is generated by a diffraction of the coherent light caused by the first grating portion, where m is an integer, and scans the second grating portion of the diffraction grating in the first direction by the coherent light and detects by the photosensor a zero order spectrum which is generated by a diffraction of the coherent light caused by the second grating portion, to thereby detect the two-dimensional position at an intersection of the first and second grating portions of the diffraction grating.</p> |
