Patent ID: 6316769
Filing Date: 2001-11-13
Classification: H01J

Abstract:
A mass spectrometer, comprising:an ion source unit disposed in a substantially atmospheric pressure region,an ion trap type mass analyzer unit for mass analyzing the ions from said ion source unit, which is disposed in a vacuum region,an intermediate pressure region having a pressure greater than that of said vacuum region and less than that of said atmospheric pressure region, which is disposed between said substantially atmospheric pressure region and said vacuum region,a first electrode having an aperture for introducing the ions from said ion source unit into said intermediate pressure region; said first electrode being disposed between said substantially atmospheric pressure region and said intermediate pressure region,a second electrode having an aperture for introducing the ions from said intermediate pressure region into said ion trap type mass analyzer unit; said second electrode being disposed between said intermediate pressure region and said vacuum region, andan energy control unit for controlling the energy of the ions introduced in said ion trap type mass analyzer unit, whereinsaid energy control unit includes an electric power supply which applies a voltage on said second electrode for controlling the energy of the ions introduced in said ion trap type mass analyzer unit.