Reflectron coaxial

Example The curved-field reflectron of a coaxial ReTOF instrument occupies a large portion D) of the total flight path s = li + D) and uses 86 lens elements... 

Fig. 4.8. Coaxial curved-field reflectron TOF spectrometer. The total length is about 1 m. Adapted from Ref. [37] with permission. John WUey Sons, 1995.

The QitTof mass spectrometer has MS" capability. Its mass resolution, m/Am, for mass 181 amu, ranges from 100-200 for a 22-cm flight-path linear TOF analyzer to 400 for a 38-cm coaxial reflectron configuration. 

The reflectron is situated behind the field-free region opposed to the ion source. The detector is positioned on the source side of the ion mirror to capture the arrival of ions after they are reflected. There are two common methods of positioning the detector. It may be coaxial with the initial direction of the ion beam. This detector has a central hole to transmit the ions leaving the source. However, the most common instrument geometry has the detector off-axis with respect to the initial direction of the ion beam. Indeed, adjusting the reflectron at a small angle in respect to the ions leaving the source allows the detector to be positioned adjacent to the ion source. 

FIGURE 3.8 Schematic diagram of the coaxial reflectron time-of-flight mass spectrometer used by Tanaka et al. (Reprinted with permission from reference 14). 

FIGURE 8.21 Coaxial, curved-field reflectron TOP with gate and pulsed valve shown. (Reprinted with permission from reference 15). 

Example The curved-field reflectron of a coaxial ReTOF instrument occupies a large portion (D) of the total flight path s = li + D) and uses 86 lens elements whose voltages are set by 85 precision potentiometers located between them [47], The distance f between ion source and reflector entrance provides sufficient field-free flight path for metastable dissociations. 

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