Vakuummätning

Vakuummätning, often translated as vacuum measurement, is the process of quantifying the pressure of a gas within a system that is significantly below atmospheric pressure. This is crucial in many scientific and industrial applications where even small amounts of gas can have a significant impact.

Various instruments, known as vacuum gauges, are employed for this purpose. These gauges operate on different principles depending on the pressure range being measured. For high vacuum ranges (typically below 10^-3 mbar), methods like ionization gauges (hot cathode or cold cathode) or thermal conductivity gauges (Pirani gauges) are common. These rely on physical phenomena that are sensitive to the low number of gas molecules present.

For higher vacuum ranges (from atmospheric pressure down to about 10^-3 mbar), mechanical gauges such as Bourdon gauges or diaphragm gauges can be used. More sophisticated gauges like capacitance manometers are also employed, which measure pressure by detecting changes in capacitance caused by diaphragm deflection.

The units of vacuum measurement can vary. Commonly used units include Pascals (Pa), millibars (mbar), Torr, and millimeters of mercury (mmHg). Understanding the specific application and the required precision dictates the choice of both the vacuum gauge and the units of measurement. Accurate vakuummätning is essential for processes like semiconductor manufacturing, thin-film deposition, freeze-drying, and scientific research involving particle accelerators.