These ions then pass through a region of field free space in the flight tube .
These ions then spread out in time , with the higher mass ions arriving later at the end of the flight tube where a time - sensitive detection system produces a mass spectrum .
These ions then pass through a region of field free space in the flight tube , and spread out in time , with the higher mass ions arriving later at the end of the flight tube where a time - sensitive detection system produces a mass spectrum .