| 摘要 |
PURPOSE:To reduce the number of solid-body scanning elements needed for MTF inspection by changing the arrangement direction of a plurality of solid-body scanning elements by pivotting them in equal numbers at the same time, and aligning the arrangement directions of a plurality of chart patterns and the scanning elements in one direction, in order to measure in two directions. CONSTITUTION:Solid-body scanning elements P1-P3 are arranged on a circular mounting plate so that the element P2 is on the optical axis of a lens 4 measured, and the elements P1 and P3 are at the same distance leftward and rightward from the optical axis, and chart pattern images Z1-Z3 are focussed in the direction of a normal T-T on the scanning elements P1-P3 respectively, in order to measure MTF on the normal T-T. Then, all the patterns are turned around the lens center by 90 deg., all the scanning elements are turned around their centers by 90 deg., and images Z4 and Z5 are focussed on the elements P1 and P3 respectively, so that the direction of all the elements and the patterns are changed into the direction of a normal R-R, and MTF on the normal R-R is measured. Thus, one scanning element can measure in both radius vector and tangent directions, so that the number of the scanning elements needed can be reduced. |
