The Microscope

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The Microscope

• Mr. Gacc/Bakka
• BHS

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The History

• Many people experimented with making microscopes
• Was the microscope originally made by accident?
  (Most people were creating telescopes)
• The first microscope was 6 feet long!!!
• The Greeks Romans used lenses to magnify
  objects over 1000 years ago.

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The History Hans and Zacharias Janssen of
Holland in the 1590s created the first
compound microscope
Zacharias Jansen 1588-1631
The First Microscope
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The History

• Robert Hooke
• Anton van Leeuwenhoek
• made improvements by working on the lenses

Robert Hooke 1635-1703
Hooke Microscope
Anton van Leeuwenhoek 1632-1723
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History

• In 1665 Robert Hooke examined a thin slice of
  cork with a single magnifying lens and observed
  tiny compartments
• He gave them the latin name cellulae, meaning
  small rooms - hence the origin of the term cell.
• He later observed cells in plant tissues and
  observed the cells were filld with juices

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History

• In the early 1700s Leeuwenhoek looked at pond
  water and called the microscopic organisms
  animalcules
• These were the first observations of living cells

• 1820 - Robert Brown
  observed a nucleus in orchid cells

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History

• In 1838, Matthius Schleiden stated all plants are
  made of cells
• Theodor Schwann stated all animals are made of
  cells .

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Cell Theory - 3 parts

• 1. Cells are the basic unit of life
• In 1855, Rudolf Virchow further extended the cell
  theory and added
• All organisms are composed of one or more cells
• 3. All cells come from pre-existing cells

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How a Microscope Works
Convex Lenses are curved glass used to make
microscopes (and glasses etc.)
Convex Lenses bend light and focus it in one spot.
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How a Microscope Works
Ocular Lens (Magnifies Image)
Objective Lens (Gathers light, magnifies and
focuses image inside body tube)
Body Tube (Image Focuses)

• Bending Light The objective (bottom) convex lens
  magnifies and focuses (bends) the image inside
  the body tube and the ocular convex (top) lens
  of a microscope magnifies it (again).

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The Parts of a Microscope
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Body Tube

• 1. The body tube holds the objective
• lenses and the ocular lens at the proper
  distance

Diagram
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Nose Piece

• 2. The Revolving Nose Piece holds the objective
  lenses and can be turned to increase the
  magnification

Diagram
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Ocular Lens or Eye lens

• 3. Magnifies the specimen image 10x

Diagram
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Objective Lenses

• 4. The Objective Lenses increase magnification
  from 4x to 10x to 40x.

Diagram
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Stage Clips

• 5. These 2 clips hold the slide/specimen in
  place on the stage.

Diagram
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Diaphragm

• 6. The Diaphragm controls the amount of light on
  the slide/specimen

Turn to let more light in or to make dimmer.
Diagram
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Light Source

• 7. Projects light upwards through the
  diaphragm, the specimen and the lenses
• Some have lights, others have mirrors where you
  must move the mirror to reflect light

Diagram
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Arm

• 8. Used to support the microscope when carried.
  Holds the body tube, revolving nose piece and
  objective lenses.

Diagram
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Stage

• 9. Supports the slide/specimen

Diagram
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Coarse Adjustment Knob

• 10. Moves the stage up and down (quickly) for
  focusing your image.
• Never use coarse adjustment under high power!!!!!

Diagram
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Fine Adjustment Knob

• 11. This knob moves the stage SLIGHTLY to
  sharpen the image.

Diagram
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Base

• 12. Supports the microscope

Diagram
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Magnification
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Magnification

• To determine your magnificationyou just multiply
  the ocular or eye lens by the objective lens
• Ocular 10x Objective 40x10 x 40 400

So the object is 400 times larger
Objective Lens have their magnification written
on them.
Ocular lenses usually magnifies by 10x
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Hand lens - 5x

• Stereo microscope -
• 10 - 60x 3d image

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Electron Microscopecan focus up 500,000x
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Tunneling - cell parts/organells
2 types of electron microscopes
Scanning - 3D image of RBCs insects
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Ocular Lens or eye lens

Body Tube
Nose Piece
Arm
Objective Lenses
Stage
Stage Clips
Coarse Adjustment.
Diaphragm
Fine Adjustment
Light Source
Base
Skip to Magnification Section
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Using a Microscope

• Start on the lowest magnification
• Dont use the coarse adjustment knob on high
  magnificationyoull break the slide!!!
• Place slide on stage and lock clips
• Adjust light source (if its a mirrordont stand
  in front of it!)
• Use fine adjustment to focus
• Use diaghram for light intensity

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Caring for a Microscope

• Clean only with a soft cloth/tissue
• Make sure its on a flat surface
• Dont bang it
• Carry it with 2 HANDSone on the arm and the
  other on the base

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Carry a Microscope Correctly
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References

• http//www.cerebromente.org.br/n17/history/neurons
  1_i.htm
• Google Images
• http//science.howstuffworks.com/light-microscope1
  .htm