User Guide

490 Series Microscope
AmScope Proprietary Page 30 of 64
4. Change the objective lens to the 10X
phase contrast lens. Objective lenses
designed for phase contrast will be
marked “Ph”, this denotes the objective
lens has a built-in phase ring.
Note: there are 3 phase contrast objectives: 10X, 40X and 100X, and
there are 3 condenser ring plates: 10X, 40X and 100X. The
corresponding objective and ring plate must work together. For
example, the 10X phase contrast objective must work with the 10X
condenser ring plate.
2.20.4 Calibrating the Phase Contrast Objective Lens and Condenser Lens
1. Remove one eyepiece from the
microscope eyetube and insert the
centering telescope.
2. Turn the microscope’s light on and look
through the telescope lens.
3. While looking through the eyepiece,
extend the eyepiece by rotating the top
counter clockwise until an image of the
objective’s phase ring and the
condenser’s annulus are clearly in
focus. Since they are both part of the
same conjugate image plane, they can
be simultaneously in focus.