Microscope

• Microscope


  An instrument used in science laboratories to visualize very minute objects such as cells and microorganisms, giving a contrasting image that is magnified
• Giovanni Faber coined the name “microscope” in 1625
• Light Microscope

  An optical instrument that employs the use of white or visible light to illuminate the object of interest so it can be magnified and viewed through one or a series of lenses
• Compound Microscope

  Uses two lenses to magnify objects; the lenses bend or refract light to make the object beneath them appear closer
• Types of Microscope


  • Compound Light Microscope
  • Electron Microscope
• Compound Light Microscope

  • Light passes through 2 lenses
  • Can magnify up to 2000x
• Electron Microscope

  • Used to observe very small objects such as viruses and DNA
  • Much more powerful
  • Uses beams of electrons rather than light
• Parts of a microscope

  • Eyepiece
  • Body Tube
  • Nosepiece
  • Objectives
  • Arm
  • Stage
  • Stage Clips
  • Diaphragm
  • Condenser
  • Coarse Adjustment Knob
  • Fine Adjustment Knob
  • Light Source/Illuminator
  • Base
• Eyepiece

  Used to look through the microscope; standard magnification is 10x
• Body Tube


  Carries/holds the eyepiece; flexible in binoculars
• Nosepiece


  Holds the objective lenses and revolves/moves them depending on magnification power
• Objectives


  Used in combination with the eyepiece to provide a range of magnification
• Arm


  Supports the upper parts of the microscope; used to carry the microscope
• Stage


  Where the specimen is placed for viewing
• Stage Clips


  Hold the specimen slides in place
• Diaphragm


  Controls the amount of light that reaches the specimen
• Condenser


  Lenses used to collect and focus light from the illuminator into the specimen
• Coarse Adjustment Knob


  Lowers the stage or objective lenses; used to focus the microscope
• Fine Adjustment Knob


  Raises and lowers the stage or objective lenses a small distance for exact focusing
• Light Source/Illuminator

  Used instead of a mirror; captures light from an external source
• Using a Microscope

  1. Always carry with 2 hands

  2. Take note of the microscope number

  3. Do not force knobs

  4. Store with cord wrapped around microscope
• Making a Wet Mount

  1. Get a clean slide and coverslip

  2. Place the specimen in the center

  3. Place 1 drop of water/stain

  4. Place the edge of the cover slip at a 45° angle

  5. Slowly lower the cover slip
• Focusing Specimens

  1. Start with scanning objective

  2. Use coarse adjustment knob

  3. Switch to low power

  4. Use coarse knob to refocus

  5. Switch to high power and use fine adjustment knob
• Using the coarse knob under high power could crack the slide or lens
• Staining Specimens

  1. Place specimen in the center

  2. Put a drop of stain on a slide

  3. Place a coverslip onto the slide
• How to use a microscope

  1. Place the slide on the stage

  2. Use stage clips to secure slide

  3. Adjust nosepiece to lowest setting

  4. Look into eyepiece

  5. Use coarse adjustment knob