Ken A Vision Research Scope T-29031, Инструкция по эксплуатации

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5
OPERATION
Illumination: On any light microscope, the ability to adjust light is probably
the most import element after the quality of the lens systems. The Ken-A-Vision
Research Microscope has 4 distinct mechanisms to adjust light intensity, and
thereby allowing for High Bright Köhler Illumination. The degree of light inten-
sity needed depends on individual conditions such as specimen
density, contrast, translucence and staining, objective magnification and
individual users eyesight Avoid turning the light onto full brightness as this
shortens the life of the bulb.
Too little or two much light is rarely recommended. Light entering into the
objective from the sub-stage illuminator may be modified by:
•
A Dimmer (Rheostat) switch on the bottom left side
• A Disc Iris diaphragm ( Field Diaphragm ) on the top of the illuminator
in the base
• A Disc Iris diaphragm ( Condenser Diaphragm ) mounted within the
Abbé Condenser
• Raising and lowering the condenser
The amount of light may also be manipulated by moving the gimbaled
condenser by using the three substage manipulating screws.
High Bright Köhler Illumination:
Köhler Illumination - Defined
Köhler illumination
is a method to reduce an old problem of transmitted
light microscopes. The filament of illuminating bulb of the microscope is often
visible in the same plane as the sample, reducing resolution and sharp focus.
One simple, partial solution is to reduce the amount of light striking the
specimen, however reducing voltage to reduce light intensity may also reduce
the breath of wavelengths (hues) reaching the specimen. Various other
modifications have been done over time including opal bulbs, or placing a
glass diffuser lens in front of the bulb. Though all these techniques work to
some degree, they tend to reduce the quality (some wavelengths of light are
lost) or the amount of incident light.
Köhler illumination can be created
on microscopes with quality diaphragms, a moveable (both horizontally and
vertically) condenser, and a variable light source. Uniformity of light is
essential to avoid shadows, glare, and inadequate contrast when taking
photomicrographs.
Köhler illumination overcomes these limitations.