| 摘要 |
<p>A prism (17) is attached to a refractive index dispersion lens (16) by inclining the incidence face (17a) of the prism (17) by a prescribed angle with respect to the end face of the refractive index dispersion lens (16) and filling adhesive (B) therebetween. In this way, the amount of light reflected from the bottom face (17c) of the prism (17) decreases in accordance with the angle of inclination of the incidence face (17a), and the interference signal formed by the reflected light from the bottom face (17c) of the prism (17) and the reflected light of a reference beam therefore weakens and the image signal (MK) decreases. Consequently, distinguishing between the image signal (MK) and the image signal (WS) produced by reflected light from the measurement subject is facilitated.</p> |
