double-exposure holographic interferometry

double-exposure holographic interferometry

[¦dəb·əl ik′spō·zhər ¦häl·ə¦graf·ik ‚in·tər·fə′räm·ə·trē]
(optics)
The study of the interference fringes generated by the superposition of two holograms of the same object, one with the object in an undeformed state and the second after a small deformation.