Chapter 5 Troubleshooting
109
5.1.3 Troubles in Ph Microscopy
Problem
Check item
There is no contrast in the phase
contrast image.
Nosepiece / objective
⃞
Place the Ph objective into the optical path. (
☞
3.9.1, 4.2.2)
Condenser module
⃞
Place the Ph module (annular diaphragm) for Ph microscopy into the optical path.
(
☞
3.4.6, 4.2.2)
⃞
Center the annular diaphragm. (
☞
3.4.7)
Combination of optical elements
⃞
Confirm that the combination of the Ph objective and the annular diaphragm is
correct. (
☞
4.2.3)
The contrast in the Ph image is poor.
Nosepiece / objective
⃞
Change the objective to the Ph objective suitable for the specimen. (
☞
4.2.3)
In some cases, for specimens whose contrast is weak in microscopy with a DLL
objective, good results might be achieved with a DM objective.
Condenser
⃞
Adjust the height of the condenser. (
☞
3.4.2)
Aperture diaphragm
⃞
Fully open the aperture diaphragm. (
☞
3.4.5)
The quality of the Ph image is poor.
Specimen / stage
⃞
Prepare a specimen suitable for Ph microscopy. (
☞
4.2.1)
Microscopy of specimens that scatter light or that have lens or prism effect will
decenter the PH module. In particular, thick live specimens, coarse specimens, and
specimens with a microplate are significantly decentered with their lens or prism
effect, resulting in image deterioration.
The image is brighter than the
background, and therefore cannot be
observed.
Specimen / stage
⃞
Decrease the phase contrast of the specimen. (
☞
4.2.1)
When a Ph objective with a dark contrast is used, if the phase contrast of the
specimen exceeds the phase contrast allowance (latitude) of the objective, the
image cannot be observed because the image is brighter than the background.
When a phase contrast specimen is created, the phase contrast can be adjusted by
the thickness of the specimen, mounting medium, or refractive index of culture
solution.
