Abstract: Several Problems on the Structure and Technology of Ion Source of Thermoelectron Bombardment GasXu Shengguo (Institute of Space Medico-Engineering,Beijing 100094,China)Received 1993-05-06Abstract: Ion source design is extremely important in developing a mass spectrometer. Performance of an ion source depends on many factors of each electrode such as structure,shape,size and electric parameters. In this study ion motion trace is revealed by simulating experiments,which for those who are interested in this field,may e.nhance their perceptual knowledge and imagery concept of potential distribution inside ionization region of an ion source and tendency of ion motion so as to make them undersand more about the focus changes of ion beam under the condition of different structures and electric parameters. In addititon,this paper expounds which ion source is worthwhile to be first selected by the performance comparison of the ion sources with different structure;it alsogives, as far as possible,an exposition of the effects of structural characteristics,electrode number,shape,geometry and electric parameter on the ion source performance by the experiment of structural adjustment. Some graphs and data are provided for reference.Keywords: ion source, experiment, design.