Microscopes

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Microscopes
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• Microscope A tool used by people to enlarge
  microscopic objects
• Microscopic extremely small, cannot be seen
  without a microscope

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• Lens- a curved transparent piece of glass that
  bends light, which may increase the size of the
  object
• Simple microscope- has one lens
• Compound microscope- has two or more lenses
• Electron microscope- uses beams of electrons to
  magnify objects, instead of light

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Parts of the microscope

• Eyepiece (or ocular)- used to look through and
  helps to magnify
• Body tube- holds the lenses at the proper
  distance so the microscope can focus
• Revolving nose piece- holds and allows the
  objective to be turned into viewing position

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• Objectives- are the lenses
• Low power is 4 times magnification. Always start
  and end with this lens.
• High power is 40 times magnification. It is the
  longest lens, never use the coarse adjustment
  knob with high power lens

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• Stage- the place that the slide is put on
• Stage clip- holds the slide in place
• Diaphragm- controls the amount of light that is
  passing through an object
• Fine adjustment knob- smallest of the two knobs,
  used to sharpen image
• Coarse adjustment knob- largest of the two knobs,
  used for a quick focus, never on high power

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• Arm- supports the microscope and is used to carry
  it
• Base- supports the microscope and is used to
  carry it
• Light source- provides the light

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Magnify

• The word magnify means make bigger.
• The number on microscope lenses tell you how much
  they magnify the image of the object you are
  looking at.
• The magnification of a lens is also referred to
  as its power.

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Total magnification

• The objective lenses have different numbers on
  them.
• To determine the total magnification of an
  objective lens and the eyepiece working together,
  you multiply the magnifications together.
• Example When you use 10x eyepiece with 4x
  objective lens total magnification is 40x.

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Using the microscope
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Using the microscope

• Carry the microscope- with one hand on the base
  and one hand on the arm
• Do not touch- the lens with your finger
• Always focus- first with the low power objective
• Do not use the coarse adjustment knob to focus
  the high power objective lens
• Use only the fine adjustment knob when focusing
  on the high power objective lens.

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Using the microscope

• 1. Place the microscope on a flat surface away
  from the edge of the table.
• 2. Look through the eye piece, adjust the
  diaphragm for the best amount of light.
• 3. Place the slide on the stage so the object is
  in the center.
• 4. Always focus first with the low power
  objective and the coarse adjustment knob.

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• A. Eyepiece
• B. Coarse Adjustment Knob
• C. Fine Adjustment Knob
• D. Arm
• E. Stage Clip
• F. ---
• G. Bodytube

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• H. Nosepiece
• I. Low power objective
• J. High power objective
• K. Stage
• L. Diaphragm
• M. Mirror/Light
• N. Base