Patent ID: 7921693
Filing Date: 2011-04-12
Classification: G01J,G01N

Abstract:
1. A spectrometer apparatus comprising: a pulsed radiation beam generator for generating a pulsed radiation beam of a pre-determined radiation wavelength; an optical cavity having a plurality of cavity modes, each cavity mode having a cavity mode wavelength; a dithering arrangement for dithering the radiation wavelength of the pulsed radiation beam and the plurality of cavity mode wavelengths such that the pulsed radiation beam quasi continuously couples into the optical cavity; a photo-acoustic cell located within the optical cavity for containing a sample to be analyzed; and a detector for detecting pressure waves generated in the photo-acoustic cell when the sample absorbs radiation from the pulsed radiation beam and for producing a detector output signal that is processable to determine a value for a concentration of an absorber in the sample.