How exactly is an image created from an electron microscope?

Question

I know that it sends a beam of electrons down that bounce off and around an image, but how is the image then created?

Answer 1

There are electrostatic lenses that focus the beam of electrons at a certain point on the sample. First the beam is deflected to one point on the sample surface, and the machine measures how many electrons "bounce" back. The more electrons "bounce" back from that point on the sample, the brighter the image is at the corresponding point in the picture being made. Then the beam is moved to the next point on the sample, and the measurement is repeated. Finally, after this has been repeated for the whole area to be photographed, the resulting picture is brighter in areas where more electrons "bounced" back and darker in areas where fewer electrons "bounced" back.

This is how a scanning electron microscope works. As the answer below this one says, there are also transmission electron microscopes which are similar, but the sample is made really, really thin, and the image is based on how many electrons pass through the sample, rather than how many "bounce" back. I had assumed your question was about the scanning electron microscope since you asked about bouncing electrons!!

Answer 2

Electron microscopes use a beam of electrons to produce their image A transmission electron microscope produces 2d photographs while a scanning electron microscope produces 3-d photographs, electron microscopes actually have a greater suitable decision and magnification potential than gentle microscopes

Answer 3

I don't believe that the first answer is correct. The second answer is correct for scanning electron microscopes.

For a transmission electron microscope, the electrons that pass through the specimen expose the film or cause the atoms of the screen to give off light. Where electrons are scattered from the specimen, they don't reach the screen or film, so those areas are dark.

Answer 4

When the electrons bounce of the substance, there wavelength's change. This change is detected by the machine and an image is formed from the electrons with different wavelengths

Answer 5

It works same as normal microscope works. Difference is just in wavelength. Since light can draw images of those things which are larger than its wavelength. since electron have very very small wavelength (particle has wave nature also) so it can draw pictures of objects having size greater than its electron’s wavelength