Microscope Calculator

Microscope Calculator Diagram
Microscope Components Eyepiece Objective Specimen Eyepiece Mag: 10x Objective Mag: 40x Total Mag: 400x NA: 0.65 λ: 550 nm Res: 0.52 μm

Microscope Calculator

What is a Microscope?

A microscope is an optical instrument used to view objects that are too small to be seen by the naked eye. It magnifies small objects using a system of lenses, allowing scientists, researchers, and students to observe microscopic structures in detail. Microscopes are essential tools in biology, medicine, materials science, and many other fields.

Formulas

Two key formulas are used in microscopy calculations:

1. Total Magnification

\[ M_{total} = M_{objective} \times M_{eyepiece} \]

Where:

  • \( M_{total} \) is the total magnification
  • \( M_{objective} \) is the magnification of the objective lens
  • \( M_{eyepiece} \) is the magnification of the eyepiece

2. Resolution

\[ R = \frac{0.61\lambda}{NA} \]

Where:

  • \( R \) is the resolution (in micrometers, μm)
  • \( \lambda \) is the wavelength of light (in micrometers, μm)
  • \( NA \) is the numerical aperture of the objective lens

Calculation Steps

Let's calculate the total magnification and resolution for a microscope:

  1. Given:
    • Objective lens magnification = 40x
    • Eyepiece magnification = 10x
    • Numerical aperture (NA) = 0.65
    • Wavelength of light = 550 nm (0.55 μm)
  2. Calculate total magnification: \[ M_{total} = M_{objective} \times M_{eyepiece} = 40 \times 10 = 400x \]
  3. Calculate resolution: \[ R = \frac{0.61\lambda}{NA} = \frac{0.61 \times 0.55 \text{ μm}}{0.65} \approx 0.52 \text{ μm} \]

Example and Visual Representation

Let's visualize the components of a microscope:

Eyepiece Objective Specimen Light path

This diagram illustrates:

  • The eyepiece (green circle) at the top
  • The objective lens (yellow circle) near the bottom
  • The specimen (teal rectangle) at the base
  • The light path (gray dashed line) from the specimen through the lenses
  • The body tube (red rectangle) connecting the eyepiece and objective