Differential-pumped electrostatic lens

Salmeron M, Schlogl R (2008) Ambient pressure photoelectron spectroscopy A new tool for surface science and nanotechnology. Surf Sd Rep 63 (4) 169-199 Ogletree DF, Bluhm H, Lebedev G, Fadley CS, Hussain Z, Salmeron M (2002) A differentially pumped electrostatic lens system fen photoemission studies in the millibar range. Rev Sci Instr 73 (ll) 3872-3877... 

Ogletree, D., Bluhm H., Lebedev G., et al. (2002). A Differentially Pumped Electrostatic Lens System for Photoemission Smdies in the Millibar Range, Rev. Sci. Instrum., 73, pp. 3872-3877. 

Figure 5. Schematic of ion sampling unit, composed of a sampling orifice, a set of electrostatic lenses, and a differential pumping system. The electric lines of force under the applied potential are drawn schematically together with an imaginary convex lens.

A compact ion attachment mass spectrometer was designed that is simple and small and fulfills all the basic requirements for lAMS the system can be used to obtain only molecular ions by detecting any chemical species in real time [93]. This custom-made apparatus (Fig. 6.11) consists of a Li+ ion attachment ion source into which a stream of gas from a capillary leak inlet is directed, an electrostatic lens system (ELS), and a quadrupole mass spectrometer and detector, all of which are installed in a vacuum-separated envelope. The system employs a single tuibomo-lecular pirmp on the vacuum envelope instead of a differential pumping system. 

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