Learn about key concepts in electron wave theory - without lots of mathematics...

1. The electron wave: The corkscrew analogy
2. Wave interference
: How electron waves add together and how we measure intensity
3. Phase threads: An easy way of measuring the phase of wave components
4. Elementary wave types: Spherical waves and plane waves - we can build up any sort of wave out of such elementary waves.
5. Diffraction at an obstacle: A simple water wave analogy
6. The calculus of wave interference: How we add together several waves, according to the rules of geometry
7. Young's slits: The simplest example of wave interference
8. Huygen's principle: The most useful concept in wave propagation
9. Fresnel fringes: A qualitative description of something we see everywhere in electron images
10. The Fraunhofer and Fresnel approximations: All to do with geometry...
11. The Fourier transform: An essential element of electron optics explained in very simple terms using a mechanical analogy
12. The sinc function: Used extensively in Fourier analysis theory: a geometrical explanation
13. The diffraction grating: The first step in understanding diffraction from a crystal
14. The Fourier transform of the diffraction grating: The first step in understanding reciprocal space
15. Crystallography: A super-simple introduction to diffraction from 3D objects
16. 3D waves and scattering: The geometry of the scattering vector in diffraction, plus some thoughts on 3D plane waves
17. Bragg's law: Scattering from planes of atoms in real space
18. Reciprocal space: A qualitative Fourier approach to understand this source of great confusion
19. The Ewald sphere: The main reciprocal-space construction for diffraction scattering in 3D
20. The convolution integral: An essential concept in imaging theory

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