microscope.notebook
October 18, 2015
Microscopes­ tools used to enlarge images of small objects so as they can be studied.
Stereoscope
Example­ cells
Electron Microscope
­3 lenses
to magnify
bigger 3D
objects
­uses beams of electrons to magnify extremely small objects
Compound Light Microscope
­uses 2 lens
to magnify
small objects.
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microscope.notebook
October 18, 2015
The Compound Light Microscope
­has two lenses (used to magnify or enlarge the image) ­two knobs to focus the image. ­images seen through the microscope are upside down and backwards.
The letter
"e" as seen
through the microscope
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microscope.notebook
October 18, 2015
Early Microscopes
­The first microscope was made in the late 1500's by putting 2 magnifying glasses together.
­In the 1600's, a Dutch fabric merchant named Anton van Leeuwenhoek made a microscope using a tiny glass bead for a lens. ­It could magnify objects up to 270 times larger than its actual size (it had a power of 270x).
­He reported seeing things in pond water that no one had ever imagined!
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October 18, 2015
Field Of View
The visible diameter across the microscope 4
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October 18, 2015
Calculating Total Magnification
Eyepiece X Objective = Total Magnification
Low Power
This means that images seen through
10x X 4x = 40x
Medium Power
10x X 10x = 100x
High Power
the microscope appear 40, 100 and 400 times bigger than they actually are!
10x X 40x = 400x
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microscope.notebook
October 18, 2015
Low Power
Stem at 40x
Medium Power
Stem at 100x
High Power
Stem at 400x
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Procedure for using the Microscope
­Always begin on LOW POWER (smallest objective lens) ­Focus by using the coarse adjustment knob first (this will bring the stage up)
­Then, use the fine adjustment to sharpen your focus.
­You may use BOTH the coarse and fine adjustment on LOW and MEDIUM POWER.
­On HIGH POWER, do NOT use the coarse adjustment knob. Use the fine adjustment ONLY!!!
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