How does an electron microscope work?

An electron microscope uses a beam of electrons to magnify objects and create high-resolution images.

Electron microscopes use a beam of electrons instead of light to create an image. The electrons are generated by an electron gun and focused onto the sample using magnetic lenses. The sample is placed in a vacuum to prevent the electrons from scattering and distorting the image.

There are two types of electron microscopes: transmission electron microscopes (TEM) and scanning electron microscopes (SEM). TEMs use a thin sample that allows electrons to pass through, creating an image of the internal structure of the sample. SEMs use a focused beam of electrons to scan the surface of a sample, creating a 3D image of the surface.

Electron microscopes have a much higher resolution than light microscopes, allowing for the observation of much smaller structures. The resolution of an electron microscope is limited by the wavelength of the electrons, which is much smaller than the wavelength of light. Electron microscopes can achieve resolutions of up to 0.1 nanometres, allowing the observation of individual atoms.

Electron microscopes are used in a variety of fields, including materials science, biology, and nanotechnology. They have revolutionized our understanding of the microscopic world and continue to be an important tool in scientific research.