Along with the transmission electron microscopes the scanning electron microscopes are extensively used in the field of science. The SEM lets us see the surface of three dimensional specimens in very high resolution. They are 10 times less powerful than the TEM, but produce sharp, high resolution, black and white images. It scans the surface of an object with focused electron beams by identifying electrons that are reflected and deflected from the surface of an object. Small objects like insects can be viewed on SEM without losing the focus even on low magnifications making it one of the best electron microscopes for generating three dimensional images. SEM is also used to provide information on morphology, and topography.
lets us see the surface of three-dimensional objects in high resolution. It works by scanning the surface of an object with a focused beam of electrons and detecting electrons that are reflected from and knocked off the sample surface. At low magnifications, entire objects (such as insects) viewed on the SEM can be in focus at the same time. That’s why the SEM is so good at generating three-dimensional images of lice, flies, snowflakes and so on.