Multireflection cells based on the development by White (1942, 1976) are becoming increasingly popular for studying the chemical composition of the ambient atmosphere by long path UV-visible absorption spectroscopy (DOAS). This is partly due to the special property of the design to eliminate negative effects of vibration and atmospheric fluctuations on the optical quality of the cell. The main parameters limiting the number of reflections (and thus achievable optical length) as well as the vibration tolerance are the size of the main mirror and the number of loci that can be fitted on its surface. Also limiting can be the total reflectivity of the mirrors. Here we present a design variant simplifying the optical alignment of the cell by replacing two pairs of about 90-deg mirrors by quartz prisms and adding a third prism to further increase the stability of the system by a factor of two. An application of a practical design based on those principles to the simultaneous measurement of NO2, NO3, and oxygen dimers (O4) is presented.

Date Published: 12 February 1993
PDF: 12 pages
Proc. SPIE 1715, Optical Methods in Atmospheric Chemistry, (12 February 1993);

Published in SPIE Proceedings Vol. 1715:
Optical Methods in Atmospheric Chemistry
Harold I. Schiff; Ulrich Platt, Editor(s)