Microscopy Concepts, Magnification, and Components

Key Definitions and Etymology

• Etymology: Derived from Ancient Greek mikrós ("small") and skopéo ("I look at").

• Microscopic: Means invisible to the eye unless aided by a microscope.

• Microscopy: The science of investigating small objects using such instrument.

• Magnification: Apparent enlargement of an object.

• Resolution: Clarity, sharpness of the image magnified.

Classification of Microscope Parts

• Mechanical Parts: Parts concerning for support and control.

• Illuminating Parts: Parts concerning light.

• Magnifying Parts: Parts concerning magnification.

Magnifying Components

• Eyepiece / Ocular Lens: Contains the lens that magnifies the image formed by the objectives.

• Objective Lenses: Magnifies the image.

  • Scanning Objective: $4\text{X}$ objective lens.

  • LPO Lens (Low Power Objective): Magnifies about $10\text{X}$; allows you to quickly scan a large area.

  • HPO Lens (High Power Objective): Magnifies about $40\text{X}$; locates those areas which need closer view.

  • Oil Immersion Objective: $100\text{X}$ objective lens.

Total Magnification

• Total magnification formulas:

  • $4\text{X} \text{ Scanning Objective} \times 10\text{X} \text{ Eyepiece} = 40\text{X}$

  • $10\text{X} \text{ Objective} \times 10\text{X} \text{ Eyepiece} = 100\text{X}$

  • $40\text{X} \text{ Objective} \times 10\text{X} \text{ Eyepiece} = 400\text{X}$

  • $100\text{X} \text{ Oil Immersion Objective} \times 10\text{X} \text{ Eyepiece} = 1000\text{X}$

• Eight magnification settings include: $40\text{X}$, $100\text{X}$, $250\text{X}$, $400\text{X}$, $1000\text{X}$.