Nikon Eclipse Ti-E, Instructions Manual, Page: 76 / 133

Chapter 3 Operation
3.11 Objective Operation
74
3.11.3 Objectives with Correction Ring
Figure 3-33 Objective with correction ring (example)
Inverted microscopes are sometimes used to
observe though the bottom plate (glass or plastic) of
a Petri dish or a culture vessel. In such a case, the
microscope may not perform optimally with standard
objectives (for glass covers with a thickness of 0.17
mm), as the thickness of the bottom plate varies
from container to container.
By using an objective with a correction ring, you will
be able to compensate for the thickness of the
bottom plate.
Note, however, that correction is not possible where
there is a change in the thickness of the bottom plate
(i.e. around the periphery of the container). Use the
correction function where the thickness of the bottom
plate is uniform.
Correction ring adjustment
1. Adjust the objective correction ring to match
the reading on the scale to the thickness of
the container’s bottom plate.
For the thickness of the bottom plate, take an
actual measurement or refer to the specifications
provided by the manufacturer.
An acrylic concentric ring is useful as it will allow
you to view the operating parts from above the
stage as you work.
2. Focus on the specimen by rotating the focus
knobs.
3. If the resolution and contrast of the image are
poor, slightly rotate the correction ring on the
objective in either direction.
This will shift the focus slightly. Readjust the
focus by turning the focus knob.
4. If resolution and contrast are improved,
rotate the correction ring slightly in the same
direction, and readjust the focus.
If resolution and contrast are lost, rotate the
correction ring in the opposite direction by
approximately twice the amount rotated in the
previous step. Readjust the focus.
Repeat the process to obtain the optimal image.
• It is recommended to note the optimal
correction ring setting for use as reference in
using containers of different thicknesses.
• The 0 mm position of the correction ring
corresponds to the position for observing a
no-cover-glass specimen on an upright
microscope.
Scale
Correction ring