Electron Microscopy Essay

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Transmission electron microscopy, or TEM, is a variation of low field, high-powered electron microscopy. Created by Ernest Ruska and Max Knoll of the Berlin Technische Hochschule in 1931, the invention of this novel microscope allowed for the surpassing of the visible light resolution barrier. Since its inception, the TEM has become a resolution standard in the field of imagery, and further advances have led to the progression of high quality atomic viewing. The development of the electron microscope in the 1930s revolutionized biology, allowing for organelles, such as mitochondria, to be seen in detail for the first time. Unlike light microscopy, TEM uses a beam of electrons, denoted as a cathode ray, to scan samples. While the traditional optical microscope is restricted in resolution by the wavelength of …show more content…
As a result of their quantum tendencies, electrons can behave as waves, resulting in easy productivity. Electrons can be generated using a hot wire, and directed through using an electron gun. The electron gun uses a circuit that is created by connecting a filament to a negative power supply, followed by accelerating the electrons to the anode plate. The electrons are coming from various angles. By creating a Wehnelt cylinder, the gun can become even more negative than electrons, forcing them into a converging pattern. The electrons are then passed through an aperture, escaping into a vacuum chamber, in an ambient pressure of 0.1 mPa. Afterwards, the electrons are subjected to a voltage, resulting in a voltage difference between the cathode and the ground in a manner that minimizes electronic collisions. The cathode ray is controlled by the electromagnetic lenses, generated by the coils that circulates around the tube. The effect of the electromagnetic lenses can be adjusted by changing the electricity flowing in the coils. The cathode ray is focused into a narrow beam and shot directly to the specimen. Formation of an image of

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