ICP mass spectrometer

Claim 1

An inductively coupled plasma mass spectrometer comprising: a sampling cone for admitting inductively-coupled plasma containing ions under atmospheric pressure; a first vacuum chamber held in a relatively low vacuum degree and connected to the sampling cone for receiving therein the admitted plasma; an ion extraction electrode for extracting the ions contained in the plasma from the first vacuum chamber to form an ion stream; an ion focusing electrode system for focusing the ion stream; a mass spectrometer for analyzing the focussed ion stream to identify the ions contained in the plasma; a second vacuum chamber held in a relatively medium vacuum degree for accommodating therein the ion extraction electrode; a third vacuum chamber held in a relatively high vacuum degree for accommodating therein the mass spectrometer and the ion focusing electrode system; a first divider for dividing the first vacuum chamber and the second vacuum chamber from each other, the first divider having therein a first transit opening for transmitting the ions from the first vacuum chamber to the second vacuum chamber; a second divider for dividing the second vacuum chamber and the third vacuum chamber from each other, the second divider having therein a second transit opening for transmitting the ion stream from the second vacuum chamber to the third vacuum chamber; and exhausting means connected to the first vacuum chamber for exhausting the plasma from the first vacuum chamber.

Claim 4

An apparatus for analyzing ions contained in plasma comprising: a plasma source for producing plasma containing ions to be analyzed; a first vacuum chamber maintained in a relatively low vacuum state and having a first aperture disposed adjacent to the plasma source for admitting therethrough the plasma into the first vacuum chamber; a second vacuum chamber maintained in a relatively medium vacuum state and having a second aperture communicating between the first and second vacuum chambers; extracting means disposed in the second vacuum chamber for extracting ions contained in the plasma through the second aperture to form an ion stream composed of the extracted ions; a third vacuum chamber maintained in a relatively high vacuum state and having a third aperture communicating between the second and third vacuum chambers; focusing means disposed in the third vacuum chamber for focusing the ion stream passing through the third aperture; and analyzing means disposed in the third vacuum chamber to receive the focussed ion stream for analyzing the ions in the focussed ion stream.

Claim 5

An apparatus for analyzing ions contained in plasma comprising: a plasma source for producing plasma containing ions to be analyzed; a first vacuum chamber maintained in a relatively low vacuum state and having a first aperture disposed adjacent to the plasma source for admitting therethrough the plasma into the first vacuum chamber; a second vacuum chamber maintained in a relatively medium vacuum state and having a second aperture communicating between the first and second vacuum chambers; extracting means disposed in the second vacuum chamber for extracting ions contained in the plasma through the second aperture to form an ion stream composed of the extracted ions; a third vacuum chamber maintained in a relatively high vacuum state and having a third aperture communicating between the second and third vacuum chambers; focusing means disposed in the third vacuum chamber for focusing the ion stream passing through the third aperture; and analyzing means disposed in the third vacuum chamber to receive the focussed ion stream for analyzing the ions in the focussed ion stream.