| 摘要 |
PROBLEM TO BE SOLVED: To obtain a wavefront inclination distribution at high accuracy by correcting a posture dispersion error and a system error in stitching measurement of the wavefront inclination distribution.SOLUTION: A measuring apparatus includes a wavefront sensor 102 for measuring inclination distributions in two directions of a wavefront 101 in each of partial areas having mutually overlapped areas. The measuring apparatus calculates a first error caused by posture dispersion of the wavefront sensor during measurement in each partial area and a second error common to respective partial areas caused by an error of a measurement system, corrects the inclination distribution in each partial area in accordance with the first and second errors and calculates the inclination distribution of the whole wavefront by connecting the corrected inclination distributions. The measuring apparatus expresses the first and second errors in each direction as linear combination of a function obtained by partial differentiation of a function expressing the wavefront, regards that a weighting coefficient of the first and second errors in the linear combination coincides between inclination distributions of two directions, and calculates the weighting coefficient so that a difference of the inclination distributions in overlapped areas is minimized. |
