Olympus U-CBE Instructions Manual page 11

5. Rotate the compensator knob and confirm that the measured portion on the center of the specimen is
dark as shown in Fig. 2-1 (Note). If it is not dark, rotate the stage by -90° and clamp.
(Note) Instead, a black interference may be observed with certain specimens (Fig. 2-2).
If the black fringe does not intersect the center of the field of view even after rotating
the stage 90°, the retardation of the specimen is outside the measurable range, and
measuring with the U-CBE or U-CTB is not possible. (See page 1)
U-CBE, U-CTB
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