Adjusting The Illumination - Unitron MEC2 Manual

Fig. 18
Aperture Iris Diaphragm: The aperture iris diaphragm is not used to control the brightness of the
image. It controls the aperture angle of the incident rays. The diaphragm is not adjusted properly
until the incident rays just fill the objective lens. At this position, the contrast and sharpness of the
image will be the best. The aperture diaphragm should be re-adjusted when changing objectives.
Field Iris Diaphragm: The field iris diaphragm is used to control the size of the field of view,
reduce the reflected rays and glare, thereby increasing the contrast of the image. Generally, the field
iris diaphragm is at the proper setting when the rays just fill the field of view of the eyepieces.
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UNITRON
MEC2 INVERTED METALLURGICAL MICROSCOPE
73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com

Adjusting the Illumination

(Figure 18)
1. Make sure the field of view is bright and
evenly illuminated, and has no filament shadow.
If there is filament shadow, adjust the condenser
adjustment knob③ to its proper position.
2. To obtain a clear, sharp image, adjust the
field iris diaphragm① and aperture iris
diaphragm (2) to their proper positions. One or
both diaphragms may need to be adjusted to
obtain the sharpest image.
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