Patent ID: 7593101
Filing Date: 2009-09-22
Classification: G01N

Abstract:
1. An apparatus comprising: (a) a cell body having a fluid flow-through passage and a light passage intersecting the fluid flow-through passage at an adjustable light pathlength fluid analysis region in the cell body, the cell body comprised of material capable of maintaining temperature and pressure in at least the fluid analysis region at least different than ambient conditions; (b) first and second light-transmissive windows in the light passage, each window having at least one crystal axis aligned longitudinally with a longitudinal axis of the window, the windows having opposed, spaced apart, substantially flat surfaces defining the adjustable light pathlength fluid analysis region, the first window having a first window holder and the second window having a second window holder, the first window rotationally isolated from the first window holder, the second window rotationally coupled to the second window holder, the first window holder able to gradually translate the first window and thus adjust the light pathlength; and (c) first and second light polarization filters positioned in the light passage.