TIME-OF-FLIGHT MASS SPECTROMETER

摘要

The amounts of shifts of mass axes are measured previously when the temperature of a vacuum container consisting of a vacuum chamber (15) and an IT block (16) and a TOF power supply section (20) for applying an ion acceleration voltage is varied, and parameters representative of a transfer function based on the response are stored in a transfer function storage section (24). When analyses are performed, a mass shift prediction calculation section (25) estimates the amount of the shift of a mass axis at present time from the temperature of the IT block (16) and the temperature of the TOF power supply section (20) at present time obtained by first and second temperature sensors (34, 35), and two transfer functions stored in the storage section (24). A mass shift correcting section (29) corrects the mass axis of a mass spectrum depending on the amount of the mass thus estimated. Consequently, even when the environmental temperature varies suddenly, a shift of the mass axis of a mass spectrum is corrected with high precision and a mass spectrum of high mass precision is ensured.