It is incoherent to write about observation of phase morphology in material science without a brief introduction of the concept and development of microscopic tools. Indeed, since the discovery of optical lenses, man’s desire to observe objects too small to be seen by human eyes has intensied. Although indirect physical and chemical processes and tools were in most cases enough to gain knowledge, the scientist always sought to observe these phenomena in their real, direct, and natural states and environment. Bacteria and micron-scale living or nonliving bodies were the rst objects to be observed using microscopic tools.