Lecture Notes: Parts of a Microscope

Overview of the Microscope

• Type: Binocular Parfocal Compound Light Microscope
  • Binocular: Two eyepieces
  • Parfocal: Objective lenses are interconnected, maintaining focus when switching magnifications
  • Compound: Uses multiple lens systems (objective lenses and ocular lens)
  • Light Source: Illuminator using visible light, limits resolution due to longer wavelengths compared to electron microscopes

Key Features of the Microscope

• Magnification:
  • Objective lenses provide varying magnification levels
  • Typically combined with a 10x ocular lens for total magnification

Parts of the Microscope

1. Ocular Lens (Eyepiece):
   • Provides 10x, 20x, or 25x magnification
2. Revolving Nosepiece:
   • Allows switching between different objective lenses
   • Objectives include: Scanning power, Low power, High dry, Oil immersion
3. Objective Lenses:
   • Scanning power: 4x magnification
   • Low power: 10x magnification
   • High dry power: 40x magnification (highest without immersion oil)
   • Oil immersion: 100x magnification
   • Total magnification factor is multiplied by ocular lens magnification
4. Focus Knobs:
   • Coarse Focus Knob: Moves stage significantly, used for initial focusing
   • Fine Focus Knob: Adjusts stage minutely for precise focusing
5. Stage:
   • Platform where the specimen is placed, secured by clips
6. Illuminator:
   • Light source for the microscope, utilizes visible light
7. Condenser and Diaphragm:
   • Condenser: Focuses light onto the specimen
   • Diaphragm: Adjusts light intensity by opening/closing aperture
8. Stage Movement:
   • Allows precise movement of slide/specimen for proper viewing

Conclusion

• Microscopes enable viewing of objects not visible to the naked eye
• The compound microscope offers a balance between magnification and resolution through its lens systems and light source

Note: Remember that total magnification is the product of the magnification power of the objective and the ocular lens.