Abstract: An ion source is formed by a chamber 2. A capillary tube 6 forms an inlet to the chamber. A heater 7 is associated with the capillary tube to heat air drawn into the chamber. An electrode 4 is provided in the chamber and maintained at a voltage in the range 100 to 500 volts. In use the source is connected to an analyzer such as a mass spectrometer 10. The capillary tube is open to the atmosphere. Pressure in the chamber is reduced, and pressure in the analyzer is further reduced. An electrical potential is applied to the electrode to create a discharge within the chamber. Ionization of air molecules within the chamber leads to ionization of any sample molecules present in the chamber. Ions are swept into the analyzer for analysis.

Abstract: An ion source is formed by a chamber 2. A capillary tube 6 forms an inlet to the chamber. A heater 7 is associated with the capillary tube to heat air drawn into the chamber. An electrode 4 is provided in the chamber and maintained at a voltage in the range 100 to 500 volts. In use the source is connected to an analyser such as a mass spectrometer 10. The capillary tube is open to the atmosphere. Pressure in the chamber is reduced, and pressure in the analyser is further reduced. An electrical potential is applied to the electrode to create a discharge within the chamber. Ionisation of air molecules within the chamber leads to ionisation of any sample molecules present in the chamber. Ions are swept into the analyser for analysis.

Abstract: A mass spectrometer for analysis of a sample 5. A laser 1 is provided to illuminate at least part of the surface of the sample 5. Laser light is conducted via an optical fiber 2 and a zoom optical system 3 to the sample. A variable ion optical system 9,10,11 is provided to extract and focus ions released from the sample 5 onto a detector 12. The optical and ion optical systems operate continuously and synchronously to vary the fields of laser illumination and view of the sample such that they are substantially confocal and equal in diameter on the surface of the sample. The sample may be a MALDI sample.