Patent ID: 6888132
Filing Date: 2005-05-03
Classification: H01J

Abstract:
1. A chemical ionization apparatus for the collection and focusing of gas-phase ions produced from chemical species, the apparatus comprising: a. a dispersive source of gas-phase reagent ions operated substantially at atmospheric pressure; b. a sample introduction means operated substantially at atmospheric pressure, wherein said means is a heated conduit for the introduction of said chemical species as gaseous substances or an aerosol; c. a reaction region receiving the outlets of said sample introduction means and said reagent ion source, which are arranged so that said gaseous substances emitted from said sample introduction means and said reagent ions from said reagent ion source interact forming gas-phase ionic chemical species; d. an analyzer chamber exposed to a high vacuum downstream of said reaction region, for receiving said gas-phase reagent ions and ionic chemical species; e. a first laminated lens sandwiched between said reagent ion source and reaction region, said lens populated with a plurality of openings through which said gas-phase reagent ions pass unobstructed into said reaction region, said lens consisting of an insulating body of material, said insulating body having a topside and an underside, said insulating body has a layer of metal laminated on said topside and said underside that are contiguous with said insulating body, said metal laminate on said topside of said insulating body is adjacent to said reagent ion source, said metal laminate on said underside of said insulating body is adjacent to said reaction region, said openings having a low depth aspect ratio, a high openness aspect ratio, said metal laminates being supplied with attracting electrostatic potentials by connection to a voltage supply for generating a large electrostatic potential ratio between said laminates and establishing an electrostatic field between said source of reagent ions and said metal laminates; and f. a second laminated lens sandwiched between said reaction region and said analyzer chamber, said second laminated lens having a central opening through which substantially all said gas-phase ions unobstructed into said analyzer chamber, said second laminated lens consisting of a second insulating body of material, said second insulating body having a topside and an underside, said second insulating body has a second set of metal laminated on said topside and said underside that are contiguous with said second insulating body, said metal laminate on said topside of said second insulating body is adjacent to said reaction region, said metal laminate on said underside of said second insulating body is adjacent to said analyzer chamber forming a deep-well region between said metal laminates of second laminated lens, said second set of metal laminates being supplied with attracting electrostatic potentials by connection to a voltage supply, and generating an electrostatic field between said reaction region and said second set of metal laminates, wherein said region of reagent ion generation is physically separated from ion reaction region.