POSITION DETECTING DEVICE, ALIGNER, AND EXPOSURE METHOD

摘要

PROBLEM TO BE SOLVED: To provide a position detecting device which is capable of carrying out an accurate position detecting operation without being substantially affected by each chromatic aberration remaining in an optical system even if wide-band lighting is used. SOLUTION: This position detecting device is equipped with an objective optical system which guides light from a mark (WM), photoelectric detectors (15 and 16) which photoelectrically detect light from the mark (WM), and a signal processing system (18) which subjects output signals from the photoelectric detectors to signal processing. The photoelectric detectors (15 and 16) are equipped with first photoelectric detectors (15a and 16a) which photoelectrically detect light of a first wavelength band from the mark and second photoelectric detectors (15b and 16b) which photoelectrically detect light of a second wavelength band from the mark. The signal processing system corrects the output signals of the first and second photoelectric detectors on the basis of aberration of the objective optical system to the light of a first and a second wavelength band.