Patent ID: 6795190
Filing Date: 2004-09-21
Classification: G01J,G01N

Abstract:
An absorption spectroscopy instrument with off-axis cavity alignment, comprising:an arrangement of two or more mirrors forming a stable optical cavity, the cavity mirror arrangement defining an axial light path in the resonant cavity wherein each reflection at each mirror thereof occurs at substantially the same spot for said axial light path, the cavity mirror arrangement also defining off-axis light paths in the optical cavity wherein successive reflections at any given mirror thereof occur at different locations for any off-axis light path, the cavity adapted to receive an absorption cell with a sample to be tested; a light source providing a light beam that is introduced into the optical cavity through a partially transmissive mirror of the cavity, the light beam being directed along any off-axis light path in the resonant cavity; a detector situated in a position to receive and measure a portion of the light beam from the resonant cavity; and means for processing data representing the light measurement from the detector for analyzing a sample received by said optical cavity.