The full form of TEM is Transmission Electron Microscopy.
Transmission Electron Microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through an ultra-thin specimen, interacting with the specimen as it passes through. An image is formed from the interaction of the electrons transmitted through the specimen; the image is magnified and focused onto an imaging device, such as a fluorescent screen, a photographic plate, or a sensor such as a charge-coupled device (CCD) camera.
The principle behind TEM involves shining a beam of electrons through a very thin sample. As the electrons pass through, they interact with the material. These transmitted electrons are then collected and used to create a highly magnified image of the sample's structure. This allows scientists and researchers to observe materials at a nanometer scale, providing insights into their composition, morphology, and crystallographic information.
