Whole-field displacement and strain measurements: application to biomechanics

There are a plethora of interference techniques which can be utilized for whole-field displacement and strain measurements. This paper contains a brief overview of some of the whole-field interference techniques which can be used for measurements in biomechanics. Rather than provide an exhaustive review of the applications of these techniques in biomechanics, however, two specific applications using holographic interferometry (HI) are presented. Although focused on HI, this discussion is pertinent to a range of whole-field interference techniques. The term whole-field is used to differentiate a class of interference techniques which provide information about displacement and strain over a large field of view, from point-by-point methods which require the repetition of the experimental protocol at an ensemble of points to produce similar information. Strain gauge measurements are a prime example of the latter class of techniques. Although whole-field methods often require an analysis at discrete points, the simultaneous acquisition of information at an ensemble of points is characteristic of these techniques.