Compact cylindrical multipass cell for laser absorption spectros...

A compact multipass cell with low fringes and high thermal stability is described. This cell is formed by two twisted cylindrical mirrors. The optical parameters are determined based on the selection criteria, which include mirror filling efficiency, interference fringes, and pattern stability. With a pattern of 174 passes, this cell gives a 22-m path length in a volume of 0.55 L. The results of an absorption measurement of oxygen at 13 091.7 cm-1 show that the fringe noise is lower than 6.54×10