Interferometric measurement techniques such as holographic interferometry and electronic speckle-pattern interferometry are valuable for measuring the deformation of objects. Conventional theoretical models of deformation measurement assume collimated illumination and telecentric imaging, which are usually only practical for small objects. Large objects often require divergent illumination, for which the models are valid only when the object is planar, and then only in the paraxial region. We present an analysis and discussion of the three-dimensional systematic sensitivity errors for both in-plane and out-of-plane interferometer configurations, where it is shown that the errors can be significant. A dimensionless approach is adopted to make the analysis generic and hence scalable to a system of any size.
© 2003 Optical Society of America
(090.2880) Holography : Holographic interferometry
(120.2880) Instrumentation, measurement, and metrology : Holographic interferometry
(120.3940) Instrumentation, measurement, and metrology : Metrology
(120.4570) Instrumentation, measurement, and metrology : Optical design of instruments
(120.6160) Instrumentation, measurement, and metrology : Speckle interferometry
David I. Farrant and Jon N. Petzing, "Sensitivity Errors in Interferometric Deformation Metrology," Appl. Opt. 42, 5634-5641 (2003)