This paper illustrates a real time desensitized outof-p1ane displacement configuration for the measurement of large deformations of a diffusely reflecting object. The optical configuration is implemented to study the behavior of engineering structures subjected to large static as well as vibration deflections. Phase stepping is provided in the optical set-up to obtain the deformation maps from the interferograms. For vibration analysis, the possibility of incorporating both phase stepping and bias vibration on a single mirror is also demonstrated. Theoretical analysis along with experimental results are presented