A shearing interferometer based on a Michelson inteferometer is propos
ed for collimation testing of a CO2 laser beam. The shear and tilt bet
ween the interfering wavefronts is obtained by replacing one or both m
irrors of the Michelson interferometer with double mirrors arranged to
act as 90 degrees or near 90 degrees prisms in retroreflecting mode.
Detailed analysis for two experimental configurations of this system a
re presented. Copyright (C) 1996 Elsevier Science Ltd.