imaging plates, CCDs, among others. Specialized imaging techniques Low energy electron diffraction (LEED) After a parallel beam of low-energy electrons interacts with a specimen, the electrons form a diffraction or LEED pattern which depends on periodicity present at the surface and is a direct result of the wave nature of an electron. It is important to point out that in regular LEED the entire sample surface is being illuminated by a parallel beam of electrons, and thus the diffraction pattern will contain information about the entire surface. LEED performed in a LEEM instrument (sometimes referred to as Very Low-Energy Electron Diffraction (VLEED), due to the even lower electron energies), limits the area illuminated to the beam spot, typically in the order of square micrometers. The diffraction pattern is formed in the back focal plane of the objective lens, imaged into the object plane of the projective lens (using an intermediate lens), and the final pattern appears on the phosphorescent screen, photographic plate or CCD. As the reflected electrons are bent away from the electron source by the prism, the specular reflected electrons can be measured, even starting from zero landing energy, as no shadow of the source is visible on the screen (which prevents this in regular LEED instruments). It is worth noting that the spacing of diffracted beams does not increase with kinetic energy as for conventional LEED systems. This is due to the imaged electrons being accelerated to the high energy of the imaging column and are therefore imaged with a constant size of K-space regardless of the incident electron energy. Microdiffraction Microdiffraction is conceptually exactly like LEED. However, unlike in a LEED experiment where the sampled surface area is some square millimeters, one inserts the illumination and the beam aperture into the beam path while imaging a surface and thus reduces the size of the sampled surface area. The chosen area ranges from a fraction of a square micrometer to square micrometers. If the surface is not homogeneous, a diffraction pattern obtained from LEED experiment appears convoluted and is therefore hard to analyze. In a microdiffraction experiment researchers may focus on a particular island, terrace, domain and so on, and retrieve a diffraction pattern composed solely of a single surface feature, making the technique extremely useful. Bright field imaging Bright Field imaging uses the specular, reflected, (0,0) beam to form an image. Also known as phase or