Increased Resolution
- Light microscopes use light and lenses to form a magnified image (make the specimen look larger)
- With a light microscope it is possible to see images of cells and large sub-cellular structures (like nuclei and chloroplasts), although stains are often required to highlight certain parts of cells
- Light microscopes have limited magnification and resolution (how well two points that are close together can be distinguished)
- Electron microscopes helped address these limitations
- The first electron microscopes were developed in the 1930s.
- Electron microscopes use beams of electrons, rather than light, to visualise specimens
- The wavelength of an electron beam is much smaller than that of visible light, which gives electron microscopes a much higher resolution and magnification
- Electron microscopes allow smaller structures can be viewed in more detail
- This has improved our understanding of sub-cellular structures such as the internal structure of mitochondria