OBSERVATION DEVICE, DETECTION DEVICE FOR MARK TO BE DETECTED AND EXPOSURE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an observation device constituted so that an object can be always accurately observed regardless of its characteristic. SOLUTION: The observation device is provided with illumination optical systems 11-15 for illuminating the object WM through an objective optical system 18 and image forming optical systems 20-26 for condensing luminous flux emitted from the object WM through the optical system 18. The illumination optical systems are provided with an illumination aperture diaphragm 12 constituted of a light transmitting part 12a and a light shielding part 12b. The image forming optical systems are provided with a 1st phase difference imparting member 23 having a 1st area 23a being conjugate with the light transmitting part 12a of the diaphragm 12 and a 2nd area 23b being conjugate with the light shielding part 12b and imparting 1st phase difference between both areas 23a and 23b and a 2nd phase difference imparting member 24 having a 3rd area 24a being conjugate with the light transmitting part 12a of the diaphragm 12 and a 4th are 24b being conjugate with the light shielding part 12a and imparting 2nd phase difference being different from the 1st phase difference between both areas 24a and 24b.