wehnelt cylinder การใช้

• Lanthanum hexaboride slowly evaporates from the heated cathodes and forms deposits on the Wehnelt cylinders and apertures.
• He received his doctorate in 1908, at the University of Berlin, under Arthur Wehnelt with a thesis was on measurements of potential in Wehnelt cylinders.
• By constructing the Wehnelt cylinder such that it has a higher negative charge than the filament itself, electrons that exit the filament in a diverging manner are, under proper operation, forced into a converging pattern the minimum size of which is the gun crossover diameter.