| 摘要 |
PROBLEM TO BE SOLVED: To conduct critical microscopic dimension measurement reproducibly and to eliminate the influence of a measuring point and orientation of a characteristic part. SOLUTION: The microscopic dimension measuring apparatus (1) comprises a light source (2), a beam forming optical system (3), and a condenser (11). Between the beam forming optical system (3) and the condenser (11), first, a first microlens array (5) is placed which comprises each microlens (I, II, III) producing a divergent light flux so that a pupil (9) of the condenser is filled. Behind the microlens array (5), a first auxiliary optical element (6) is placed which has positive refracting power so that the pupil (9) of the condenser is placed on a focal plane. Behind the first auxiliary optical element (6), a second auxiliary optical element (16) having positive refracting power is placed. Behind the second auxiliary optical element (16), a second microlens array (17) is placed. Illumination based on the Kohler's principle is produced, and highly homogeneous field illumination appears which has rotationally symmetric intensity distribution with respect to the pupil (9) of the condenser simultaneously. COPYRIGHT: (C)2004,JPO
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