Quadrupole Mass Filter

A quadrupole mass filter is a device used in scientific instruments to sort and detect ions based on their mass-to-charge ratio. It consists of four parallel metal rods with oscillating electrical voltages applied. Ions pass through the center, and depending on their mass, the electric fields either allow them to pass through or cause them to be deflected and dropped out. By adjusting the voltages, specific ions can be selected for measurement. This allows precise analysis of complex mixtures, such as identifying molecules in a sample, in techniques like mass spectrometry.