Abstract
A two-channel differential polarimeter suitable for the continuous measurement of the angular displacement of a rigid body about a single axis is described. A prototype of this design was assembled to make angular displacement measurements on a bend-bar specimen during a fracture-mechanics experiment. A half-wave plate attached to the bend bar rotates the linear polarization of a He−Ne laser beam as the specimen is deformed during the test. The sensitivity of the prototype instrument was limited by inhomogeneity in the wave plate, and thus did not approach the theoretically predicted values for resolution on the order of 10−7 deg. Based on preliminary results, however, this technique shows promise for quasistatic as well as dynamic bend-bar testing.
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Wagner, J.W., Deaton, J.B. & Hackett, E.M. Laser polarimeter for measuring angular displacement of bend bars. Experimental Mechanics 28, 45–49 (1988). https://doi.org/10.1007/BF02328995
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DOI: https://doi.org/10.1007/BF02328995