Dual-reference holographic interferometry with a double pulsed laser

Abstract

Dual-reference holographic interferometry is applied to transient deformation phenomena with a double pulsed laser. Automated interpretation of the interfering pattern of two reconstructed images produced by the double exposure hologram is achieved with a precision of λ/35. The lateral motion which causes the reduction of fringe visibility is compensated by varying the reference angle in reconstruction. Two switching methods to synchronize the two pulses as two reference beams are shown. Its use in measuring the displacement and deformation of a solid diffusely scattering object is demonstrated.