Chapter 3 Detailed Explanation
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Notes on limits on objectives
When a phase contrast slider's bright-field position is used, the following limits apply depending on the
objective:
•
For objectives of NA 0.75 or higher, part of the field of view is lost (vignetting occurs).
•
For objectives of NA 0.95 or higher, loss of field of view caused by vignetting, or reductions in peripheral
light intensity occur.
Note that when a phase contrast slider's bright-field microscopy position is used, the following limits apply
depending on the objective:
•
For PH sliders (10x/40x): PH1: NA 0.25 - 0.5, PH2: NA 0.55 - 0.85
•
For PH sliders (100x): PH3: NA 0.9 - 1.4
Phase contrast slider
Phase contrast microscopy requires a phase contrast slider with a mounted Ph annular diaphragm. A phase
contrast result can be obtained by correctly matching the Ph annular diaphragm and the phase ring of the Ph
objective.
Ph code
Ph objectives are labeled with a Ph code according to the size of the phase ring. The code can be [Ph1], [Ph2],
or [Ph3]. To use a Ph objective, bring the Ph annular diaphragm that has the same code as the Ph objective's
Ph code into the optical path. If you use a Ph annular diaphragm with a different Ph code from the Ph
objective, a phase contrast result cannot be obtained.
Aligning an annular diaphragm and phase ring
The phase contrast image is subtly affected by overlap between the annular diaphragm and phase ring. When
performing strict observation or photography, confirm that the annular diaphragm and phase ring are
concentric for each magnification.
Adding slight eccentricity to the annular diaphragm and phase ring creates a shadowing effect, producing a
three-dimensional image. Use this technique as required by the specimen.
Using GIF filters
The contrast of a phase contrast image is improved by bringing a GIF filter (green interference filter) into the
optical path. GIF filters are installed on top of the field lens.
3.10.2 Tips for Simple Polarizing Microscopy
Simple polarizing microscopy is an observation method for measuring polarization, refraction, and other
states of the specimen by bringing the analyzer and polarizer into the microscope's optical path to limit the
light's vibration direction.
Of the polarizing microscopy methods, this microscope only supports simple polarizing microscopy. Polarizing
microscopy using sensitive color is not supported.
Operating the polarizer
•
Setting the polarizer to a horizontal orientation causes the analyzer and polarizer orientations to converge
at a right angle. This state is known as “crossed Nicol.”
•
When the polarizer is removed and only the analyzer is brought into the optical path, this state is known
as “open Nicol.”