Hot-filament Ionization Gauge
“How can we measure the pressure in a vacuum?”
Vacuums are some of the most important phenomena in modern day engineering and physical science research. By being able to measure them, we can determine what is and what is not a vacuum. One way to do this is by using a hot-filament ionization gauge. Hot-filament ionization gauges work by running electrons through a wire coil, which are then attracted to a central grid. These electrons will collide with gas molecules and will ionize. A measurement of the amount of ionization will tell us how many molecules are in the vacuum, and therefore what percentage of the surrounding medium is a vacuum.