| 摘要 |
PROBLEM TO BE SOLVED: To prevent an image of a foreign object such as a flaw, a dust, and a defect of an optical element from being superimposed on an intermediate image and acquire a clear final image even if the intermediate image is formed at a position coincident with a position of the optical element.SOLUTION: Provided is an observation device 1 comprising: an imaging optical system 3 that includes imaging lenses 11, 12, and 15 forming a final image IF and intermediate images II, a first phase modulation element 10 disposed to be closer to an object than any one of the intermediate images II and applying a spatial disarray to a wavefront of light, and a second phase modulation element 14 disposed to be closer to the final image IF than one or more intermediate images II and cancelling the spatial disarray applied to the wavefront of the light; a light source 6 disposed to be close to the object; an XY scanning unit 13 that includes first and second scanners 13a, 13b disposed to be apart from each other in an optical axis S direction; and a photodetector 5 detecting the light, the two phase modulation elements 10, 14 being disposed at positions optically conjugate to the first scanner 13a disposed to be close to the light source 6 and having one-dimensional phase distribution characteristics changing in a direction coincident with an illumination light scan direction.SELECTED DRAWING: Figure 1 |
