7
8. (M3700 series only) Set the diopter adjustment which is designed to
help compensate for the difference between the user’s eyes. To
adjust, first bring the specimen into perfect focus by using the
coaxial focusing knobs while looking through the eyepiece with the
right eye only (close your left eye). Now, using your left eye only
(close the right eye) turn the left eye diopter only (don’t touch the
focus controls) to obtain a crisply focused image. The diopter
adjustment is now set and no further adjustment will be needed
until a new operator uses the scope.
9. Rotate the nosepiece to the next higher power objective. A slight
turn of the fine focusing knob may be required to bring the image of
the specimen into sharp focus. Once the specimen is in focus with
the highest power objective, it will be in focus with each lower
power objective.
OIL IMMERSION (Only for models with a 100X objective)
When light rays pass through air from the specimen to the objective
lens, they are distorted slightly, a phenomenon known as refraction.
This is usually not a problem at a magnification of 400X or lower.
However, at a magnification of 1,000X and above, refraction becomes
problematic. This problem is reduced significantly by placing a thin
layer of very clear, viscous oil between the slide and tip of the objective
lens. The result is a much clearer image at 1,000X because the oil has
the same light transmitting properties as glass. Using oil slightly
increases the resolution and brightness of the image. Usually a very thin
slide (size #1) is used for oil immersion because at this magnification,
the working distance is very small and is critical to focusing the
specimen. Good quality glass (not plastic) cover slips should be used. If
their thickness is over 0.17mm, the objective will not resolve properly,
because the specimen cannot be moved close enough to the objective
lens to be in focus.
Place a tiny amount of oil (only 1 drop should be sufficient) onto the
slide prior to rotating the 100XRD objective into position. It is essential
to thoroughly clean the objective tip after use to prevent damage and
to ensure that an image can be seen clearly the next time the objective
is used. Please contact Swift Optical or your authorized Swift dealer for
the appropriate immersion oil to use.
IMPORTANT: The working distances of the 40XRD and 100XRD objectives
to the slide surface are very small and although these objectives are
