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Phase contrast
Use of phase contrast with the iScope
microscope
The phase contrast method was designed in
1934 by the Dutchman Frits Zernike to
observe very thin or transparent objects.
This technique uses the fact that light
travelling through tissue undergoes a phase
shift due to diffraction.
By recombining the phase shifted light with
the background light, a contrasted image
appears in the eyepiece
Using the Phase Contrast Slider
1.
Keep the phase contrast slider face up (text up); insert it from left to right into the
condenser slider socket as the direction of the arrow pointed.
2.
Each slider has 3 positions, 2 phase contrast positions and in the center of the slide the
bright field position for normal use without phase contrast. Each phase contrast objective
used has to be matched with the phase contrast ring on the slider. For example: when the
10x phase contrast objective is used the slider should be positions to match the 10 phase
diaphragm).
Note: the phase diaphragms in the sliders are pre-centered do not need to be adjusted in
operation.
