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Microscopy and imaging technologies encompass techniques to magnify and resolve details of objects beyond the capabilities of the unaided eye, often providing information about structure, composition, and dynamics at micro- to nanoscale. The field integrates physics, chemistry, biology, and engineering and includes methods that use visible light, electrons, or scanning probes to generate images or data.

Historically, light microscopy emerged in the 17th century and advanced with improvements in lenses, illumination, and staining, enabling visualization of cells and microorganisms. The mid-20th century brought electron microscopy, which uses electrons rather than photons to achieve much higher resolution. The first transmission electron microscope and subsequent scanning electron microscope expanded the ability to study internal structures and surface morphology, respectively. In recent decades, scanning probe techniques and advanced optical methods have broadened capabilities for surface mapping, spectroscopy, and live-cell imaging.

Major families of techniques include optical microscopy, which encompasses brightfield, phase-contrast, differential interference contrast, fluorescence, confocal, and super-resolution methods that surpass the traditional diffraction limit. Electron microscopy includes transmission electron microscopy for internal structure and scanning electron microscopy for surfaces, both requiring high vacuum and extensive sample preparation. Scanning probe microscopy, such as atomic force microscopy and scanning tunneling microscopy, provides topographic and chemical information at atomic scales. There are also correlative approaches that combine modalities to link structural detail with molecular identity.

Applications span biology, medicine, materials science, and nanotechnology. Challenges include sample preparation artifacts, radiation damage, resolution limits, and data management. Ongoing developments—such as cryo-electron microscopy, live-cell super-resolution, and automated imaging workflows—continue to expand what can be observed and measured with microscopy and related imaging technologies.