Patent ID: 6677604
Filing Date: 2004-01-13
Classification: G01N

Abstract:
An apparatus for detecting the spectra of light emitted by a plasma at plural locations along the plasma, comprising:a) an optical system; b) an optics mount, coupled to said optical system, for positioning said optical system to receive light emitted from the plural locations; c) a beam splitter arranged so as to receive light from said optical system and direct the light along first and second optical paths; d) first and second detectors respectively arranged downstream of said beam splitter to convert the light along said first and second optical paths into respective first and second electrical signals representative of the intensity of light incident said first and second detectors, wherein the first and second detectors detect different wavelength ranges of the light; and e) a controller configured to process said electrical signals to determine a property of said plasma at each of said plural locations.