OPTO-EDU A63.7069, Instruction Manual

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not be changed.
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Click the [Condenser Lens Reversal Switch] button shortcut toolbar, the state of reversal
switch of condenser lens can be changed (on or off).
3.3.8. Objective Lens
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Dragging the scroll bar of [Objective Lens] on panel with mouse to control objective lens. It is
divided into coarse, fine and tiny adjustment. Coarse adjustment can change exciting current
of objective lens. Fine adjustment and tiny adjustment are set for observing image with high
magnification of tens of thousands times. The step size from coarse to fine is 10 times, also is
10 times from fine to tiny.
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For users ’ convenience, adjusting objective lens can operate as follows: move cursor on the
collected image, press left key and drag.
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The objective lens focuses electron spot on the surface of specimen. Different focus current
of objective lens can obtain different focal length; within the same scanning deflecting
magnetic field, the scanning range of electron beam on specimen is not the same; namely,
magnification is different, the software corrects magnification automatically according to the
objective lens current value.
3.3.9. Objective Lens Reversal Switch
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Objective lens reversal is realized by reversing the current of objective lens. This function is
used to degauss objective lens.
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Operating steps: open reversal of objective lens, and then switch it off. At this time, the image
will be defocusing. Adjust objective lens to focus the image. Repeat this step until the image
will not defocus.
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Click the [Objective Lens Reversal Switch] button on shortcut toolbar, the state of
objective lens reversal switch can be changed, on or off.
3.4.10. Magnification
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By operating the button on magnification control, user can adjust the magnification.
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The software calculates working distance according to selected magnification and focal length
of objective lens, then corrects magnification according to the working distance, and displays
the corrected magnification. The software timely corrects scanning deflection according to HV
value to make sure that the change of HV value has no influences on magnification.
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For users ’ convenience, adjusting magnification can operate as follows: move cursor on the
collected image, rolling mouse wheel.
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WD: Working Distance is the distance when the image is clearest.