In temporal speckle-pattern interferometry deformation information is extra
cted by a Fourier transform technique from the speckle pattern that is reco
rded over a period of time as the object is deformed. A limitation of the e
xperimental arrangements reported to date is that the direction of the defo
rmation cannot be determined. We propose removing this limitation by using
the heterodyne principle. Some experimental results that were obtained by u
se of a rotating half-wave-plate frequency shifter are presented. (C) 2000
Optical Society of America OCIS codes: 120.6160, 040.2840.