| 摘要 |
<p>PURPOSE:To accomplish a sufficient observation and inspection of a pattern by illuminating a transparent substrate having a pattern formed on one surface thereof, and providing an optical projection system for projecting this pattern on a projection plane and an optical view system for viewing the pattern projected on the projection plane. CONSTITUTION:A photomask 1 to be examined is placed in a position close to a projection plane 2 and in parallel with the projection plane. On the optical axis perpendicular to this projection plane 2 and above the photomask 1, an objective lens 3, a half mirror 4, an imaging lens 5 and a sensor 6 are disposed, and a light source 7 is placed on the optical axis rectangularly refracted by the half mirror 4. A contact lens 8 and a condensing lens 9 are placed correspondingly to the light source 7. Whereby an optical projection system is constructed for illuminating the photomask 1 form above to project its pattern on the projection plane 2. On the other hand, the objective lens 3, half mirror 4 and imaging lens 5 will form the pattern image projected on the projection plane 2 on the sensor 6, which are all constructing an optical observation system.</p> |
