Reflectron Tof (Retof)-MS.
In this instrument, a single stage or a dual stage reflectron is used at the end of the flight tube, which leads to improvement in mass resolution. The reflectron located at the end of the flight tube, is used to compensate for the difference in flight times of ions with same m/z but different kinetic energies.

Schematic Representation of Basic Components of a Reflecting TOF Mass Spectrometer