A reflectron is an electric field that reverses the direction of flying ions in the analyzer section of a time-of-flight mass spectrometer (TOF-MS). TOF-MS instruments come in two main configurations: linear and reflectron. As their name implies, reflectrons are a key component in reflectron-type instruments. A reflectron is often incorporated into a TOF-MS to achieve higher sensitivity and mass resolution.
The principle of the reflectron
The ions of the sample molecules generated in the ionization section are accelerated by the electric potential difference with the grid electrode and enter the reflectron through the flight tube. The entrance of the reflectron is at ground potential, and an opposing electric field is generated by a series of electrodes held at increasingly higher potentials. This retarding electric field, acting as an "ion mirror," slows the ions and reverses their trajectory toward the detector.
The high voltage for the reflectron is supplied by a reversible high-voltage power supply, which allows its polarity to be switched for the detection of either positive or negative ions. In addition, the potential on each of the reflectron's electrodes is typically generated using a resistive voltage divider (high-voltage divider). TOF-MS detects ions using a microchannel plate (MCP).
- Related words:
Recommended products
Matsusada Precision offers a range of reversible (bipolar) high-voltage modules ideal for reflectron applications.
