Patent ID: 6384411
Filing Date: 2002-05-07
Classification: H01J

Abstract:
An ion source comprising:a body having a gas passage defined therein, a gas inlet connected to the gas passage, and an orifice defined in the body and connected to the gas passage; a capillary through which a sample solution flows towards a tip of the capillary, at least a portion of the capillary being inserted into the body so that at least a portion of the capillary is surrounded by at least a portion of the gas passage, and so that a tip portion of the capillary including the tip of the capillary extends at least partially into the orifice; a gas supplier, connected to the gas inlet, which supplies a gas through the gas inlet into the gas passage to form a gas flow through the gas passage along the capillary and through the orifice past the tip of the capillary so that the gas flow sprays the sample solution from the tip of the capillary, and which regulates a pressure of the gas in the gas passage to adjust a characteristic value F/S to a predetermined value, where F is a flow rate of the gas flow at standard conditions (20Â° C., 1 atmosphere), and S is a difference between a cross section of the orifice and a cross section of the tip portion of the capillary in the orifice; and adjusting means for adjusting an exposed length of the capillary, the exposed length of the capillary being a distance between the tip of the capillary and an external surface of the body at the orifice.