Microscopy: Light vs. Electron Microscopes

Light Microscope (LM)

  • How it works: It uses visible light to illuminate a specimen and produce an image.

  • Magnification: Can magnify objects up to about 1500 times.

  • Resolution: Can distinguish objects as small as 0.2 micrometers.

  • Limitations: Cannot see objects smaller than 0.2 micrometers, cannot study the internal structure of bacteria.

Electron Microscope (EM)

  • How it works: It uses a beam of electrons to illuminate a specimen and produce an image.

  • Magnification: Can magnify objects up to about 250,000 times.

  • Resolution: Can distinguish objects as small as 0.2 nanometers.

  • Types: Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM).

  • Limitations: Requires a vacuum chamber, and cannot be used to study living organisms.

Key Points:

  • Electron microscopes offer significantly higher magnification and resolution compared to light microscopes.

  • Light microscopes are better suited for studying living organisms due to their ability to operate in air.

  • The type of microscope used depends on the specific research question and the size of the objects being studied.

  • The term "LM 109X" indicates that a photomicrograph was taken with a light microscope and magnified 109 times.