8
U-CBE, U-CTB
4-1
Berek Compensator (U-CBE), Thick Berek Compensator (U-CTB)
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)