Question: Because your building a gigantic microscope surely the knowledge would be greatly improved for visual impact but wouldn't a gigantic microscope just be a repeat of an already developed microscope?

Marcus Gallagher-Jones answered on 19 Mar 2012:

Well not exactly. For starters it doesn’t really look like a microscope. In fact I only use the term because it is used to look at small objects and it follows simmilar principles to a microscope. We first take a beam of light, in this case X-rays, and focus them onto an object. The light bounces off the object and we record the way in which the light bounces (or scatters). In a normal microscope you would pass this scattered light through a second lens to focus it onto your detector (for normal microscopes this is your eyes.)

In our experiments we don’t use a second lens but take the scattered light and use complex computer programs to work out how the light would be refocussed. For normal microscopes the resolution, how well you can distinguish different objects, in limited by the wavelength of the light. Typically it is difficult to see anything smaller than a few hundred nm as this is the smallest wavelength of visible light. Using X-rays it is possible to see down to the atomic level as x-ray wavelengths are similar to the size of atoms. Using this technique we can look at the organisation of materials on an atomic scale.

Normally people use crystals to do this due to a process known as braggs diffraction. In crystals you have many repeating units of the same object in a particular order. When light hits a region of one unit it is scattered in a particular way. If another photon of light hits the same spot on a different unit it will scatter in the same way. When the oscillations (the ups and downs) of photons match they interact and act as one more powerful photon.

In these experiments the signal is weak from scattered X-rays so using crystals you can get a more powerful signal. One thing people are concerned with is that crystallised materials may not act in the same way as their uncrystallised form. By using a very powerful X-ray laser we hope to be able to get a strong enough signal from un crystallised sample.

Another big difference between our microscope and a standard microscope is the penetrance of X-rays. Using X-rays it is possible to see through objects and get an impression of internal structures. Using this technique we can see inside of cells without staining them or cutting them up, which are the usual methods for seeing inside of cells.