| 摘要 |
A mass spectrometer is disclosed comprising a first chamber (10) and a se cond chamber (5). The second chamber (5) is located downstream of the first chamber 10 and an inter-chamber aperture (12) is provided between the two ch ambers (5,10). An ion guide (13) is located in the first chamber (10) and an ion mobility spectrometer (6) is located in the second chamber (5). Helium gas is provided to the first chamber (10). As ions are accelerated towards t he ion mobility spectrometer 6 from a relatively low pressure region they pa ss initially into the first chamber (10). The helium gas provided in the fir st chamber (10) minimises ion fragmentation and ion discrimination effects a s ions are accelerated into a relatively high pressure region. The ions are then transmitted by the ion guide (13) and are subsequently transmitted to t he ion mobility spectrometer (6) located in the second chamber (5). |
