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

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Differential Interference Contrast Microscopy

An analyzer, a polarizer, an object lens side DIC slider, and a condenser side DIC module are required for differential
interference contrast microscopy, which observes clear colorless specimen or undyed specimen at high contrast.
An Ni-E focusing nosepiece system can be used for differential interference contrast microscopy in the infrared region
(λ=850 nm to 950 nm) and in the visible light region (λ=430 nm to 770 nm).
When performing IR-DIC (infrared differential interference contrast) microscopy, attach a DIC analyzer cube IR to the
epi-fluorescence turret and a polarizer IR to the polarizer turret.
When performing differential interference contrast microscopy in the visible light region, attach a DIC analyzer cube VIS to
the epi-fluorescence cube turret and a polarizer VIS to the polarizer turret.
When performing differential interference contrast microscopy in the visible light region, differential/epi-fluorescence
microscopy can be performed simultaneously by inserting an FL/DIC analyzer slider in the slot at the right top of the
epi-fluorescence cube turret instead of using the analyzer cube.
The objective side DIC slider is inserted in the slot on the object mount for both the slider nosepiece and single nosepiece
and the condenser side module is attached to the turret of the LWD condenser.
The polarizer is attached to the polarizer turret mounted on the field lens.

Tips for Differential Interference Contrast Microscopy

16.1
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, Section 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 in the epi-fluorescence cube turret 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 "3 IR-DIC (Infrared Ray Differential Interference Contrast) Microscopy Procedure - 19 Adjust
the orientation (vibration direction) of the polarizer and analyzer".)
Combination of DIC slider on the objective and DIC module on 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 contrast 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 accordingly. For details, see
the table "Combination of DIC Slider on the Objective and DIC Module on the Condenser" in Chapter 1 "3. Assembly
Method - 9 Attach the condenser" in the "Assembly/Maintenance" instruction manual.
Chapter 3
Individual Operations
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