Differential Interference Contrast Microscopy; Tips For Differential Interference Contrast Microscopy - Nikon Eclipse Ni-E Instruction Manual

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Differential Interference Contrast Microscopy

The differential interference contrast microscopy in which a transparent or achromatic sample is observed with higher
contrast requires an analyzer, polarizer, and DIC slider on the objective and DIC module on the condenser side.
The analyzer and DIC slider for the objective are inserted to slots of the nosepiece when used, therefore use a DIC
nosepiece with slots for the differential interference contrast microscopy. Use a dry-type universal condenser or oil-type
DIC condenser to which the DIC module can be attached.
17.1

Tips for Differential Interference Contrast Microscopy

Critical optical adjustments
Especially, in the differential interference contrast microscopy, the following two optical adjustments are critical.
Inappropriate adjustment will result in unclear images. Operate with due care.
■ Focusing and centering the condenser
Adjust the condenser position so that the light passing through the condenser forms an image at the correct position
(center of the optical path) on the surface of the sample. Properly focus on the field diaphragm image, and make
adjustment so that its center matches the center of the field of view and its size is close to the field of view. (See
Chapter 3 "7 Focusing and Centering the Condenser".)
■ Adjusting the orientation of the polarizer and analyzer
The basic performance of the differential interference contrast method can be determined by this adjustment.
Adjust the orientation of the analyzer attached to the nosepiece and the polarizer on the field lens. The orientation of
the analyzer is fixed in Ni-E. Adjust the orientation of the polarizer to find a position where field of view is darkest. (See
Chapter 2 "5 Differential Interference Contrast Microscopy Procedure - 14 Adjust the orientation (vibration direction) of
the polarizer and analyzer".)
Combination of DIC slider for the objective and DIC module for the condenser
The differential interference contrast microscopy requires a DIC slider and a DIC module on the objective and condenser
sides respectively. A combination of the DIC slider on the objective side and the DIC module on the condenser side varies
depending on the objectives used. Note that an inappropriate combination may result in an inability to produce an
interference image, or a significant degradation of contrast.
A dedicated DIC module is designed to provide higher contrast or resolution for particular microscopy purposes. Note,
however, that in principle contrast and resolution compete under differential interference contrast microscopy (i.e.
increasing the contrast will degrade the resolution, and vice versa), so select the combination of the DIC slider on the
objective side and the DIC module on the condenser side accordingly. For details, see the table "Combinations for the DIC
Slider for the Objective and the DIC Module for the Condenser" in Chapter 1 "3. Assembly Method - 18 Attach the
condenser." in the "Assembly/Maintenance" instruction manual.
Slide and Cover Glass
In the differential interference contrast microscopy, it is especially important to use a clean, distortion-free slide and cover
glasses.
Chapter 3
Individual Operations
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