| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a shearing interferometer capable of visualizing refractive index distribution in a transparent object, quantitatively measuring refractive index of an object to be inspected, and measuring optical information distribution in a depth direction of the object to be inspected.SOLUTION: Between a light source 1 and an imaging optical system 5, the shearing interferometer includes: a first diffraction grating 2 provided on a light source side; and a second diffraction grating 3 provided on an imaging optical system side. Light from the light source 1 is made to pass through an object 4 to be inspected installed between the first diffraction grating 2 and the second diffraction grating 3, and light having passed through the imaging optical system is made to interfere on an image surface, to generate carrier fringes. The light source 1 is composed of an incoherent light source. The imaging optical system 5 forms an image of the object 4 to be inspected disposed at an object point 6 between the first diffraction grating 2 and the second diffraction grating 3, and includes an objective lens. The first diffraction grating 2 and the second diffraction grating 3 are perpendicular to an optical axis, have the structure where slit directions are parallel to each other, and are disposed so as to have non-imaging relation.</p> |
