| 摘要 |
PROBLEM TO BE SOLVED: To promptly and highly accurately detect a position of a mark provided on a rear surface of the object to be measured.SOLUTION: A detection device which detects a mark provided on a rear surface of the object to be measured comprises a first detector, a second detector, and a processing unit. The first detector illuminates the mark from a surface side of the object to be measured and detects an image of the illuminated mark. The second detector is disposed in a position in which a relative positional relation with the first detector is fixed, and detects a surface position of the object to be measured. The processing unit obtains the information indicating a focus state of the image of the mark in the first detector on the surface position detected by the second detector. |
