Question: When you sit in front of a microscope, how do you record your data?

Jenni Tilley answered on 20 Jun 2011:

Well, first I need to tell you that I use lots of different microscopes:

1) Electron Microscope – I shine a beam of electrons on to my sample and by catching the electrons that are deflected I can image the topography (surface characterstics) of my sample. I then look at the images to see if there are any changes. Some people shine the electrons through their sample (whichneeds to be very thin) so produce a diffraction pattern – the electrons are diffracted by the atoms in the sample and by analysing the pattern they work out how their atoms are arranged.

2) Atomic Force Microscopy – I scan a very scarp probe across a sample and measure the bending of the probe due to interactions with atoms. By measuring the deflection I can both image my surface (tell the height of fibres for example), and find out more about the atoms present – different atoms produce different forces between the probe and the sample, producing different amounts of probe bending. I also poke the probe into the surface and measure how much deflection I get for the amount of force I apply. By analysing a graph of force versus distance I can work out how stiff my sample is. You can see an Atomic Force Microscopy Image on my profile

3) Optical Microscope – I take images of samples that I have stained with various dyes. Different dyes stick to different chemcials in the sample and so using some image analysis software (sophisticated versions of Photoshop!) I can analyse the proportions of different chemicals in my samples. This is all a bit hand wavy though so I also use

4) Infra red and Raman Spectroscopy – I shine an infrared beam or a laser beam at my sample. The chemical bonds in my sample abosrb some of the energy and vibrate. Different bonds absorb energy at different wavelengths. I then look at what bits of the energy wave are missing once the wave have passed through the sample, to work out what bonds are present in my sample. This produces a spectra of wavelength versus intensity of energy – less intensity at certain wavelngths implies that the bond that absorbs at that particula wavelength is present. You’ll do lots about this if you do A Level Chemistry.

Essentially my microscopes gather lots of different forms of data which my computer converts to images or graphs, and I can then analyse using software like photoshop and excel. Does that answer your question?