| 摘要 |
PROBLEM TO BE SOLVED: To more accurately grasp the optical characteristics of an image formation type optical system. SOLUTION: A main control system 20 changes a position regarding the direction of the light axis of a mark board FM where a plurality of marks GM for measurement having a different form is formed, and at the same time repeatedly picks up the image of the marks for measurement using an optical system in the image formation type optical system such as an optical system in a mark detection system AS, and obtains specific aberration (aberration regarding the direction of light axis such as a best focus position, coma aberration, and spherical aberration) in an optical system based on each of the image pickup signal of each mark for measurement, namely an image pickup signal corresponding to the direction and position of the light axis of each mark for measurement. In this case, a mark in a size corresponding to a partial region in a visual field is used as each measurement mark for reading the image pickup signal, or the image pickup signal of the mark occupying the entire surface of the visual field is read, and arithmetic processing is made using only a signal at the partial region in the visual field, thus detecting the optical characteristics corresponding to the partial region in the visual field. |
