| 摘要 |
PROBLEM TO BE SOLVED: To obtain appropriate information concerning the shape, such as the warp, of a measurement object.SOLUTION: A measurement device 10 includes: a first light source 4 for irradiating a grating 2 disposed facing a measurement object 1 with first light 4a of wavelength λat an angle αfrom one side of the vertical plane 2a of the grating 2; and a second light source 5 for irradiating with second light 5a of wavelength λ, differing from the wavelength λ, at an angle αfrom the other side. The measurement device 10 further includes an image-capturing unit 3 for capturing the image of an interference fringe produced when the grating 2 disposed facing the measurement object 1 is irradiated with both the first light 4a and the second light 5a and disposed at the side of the grating 2 opposite the measurement object 1 side. Using the measurement device 10, the image of an interference fringe in which the effect of a shadow causable by either the first light 4a or the second light 5a is suppressed is obtained, and appropriate information concerning the shape, such as the warp, of the measurement object 1 is obtained on the basis of the image.SELECTED DRAWING: Figure 5 |
