Holographic Interferometry or Fringe Interpretation

摘要: As seen in Chap. 3, the principal property of holograms is storage wave fields which may be reconstructed at any later time. was already mentioned introduction, it for this reason that two slightly different fields, do not exist simultaneously, brought to interfere. Analysis resulting interference fringes (Fig. 4.1) constitutes problem holographic interferometry, first experiments were performed around 1965 [4.1–14]. In particular, if both are recorded successively on same hologram (with reference source) and together, we obtain well-known double exposure or frozen fringe effect. Using technique, measurements almost completely insensitive small modifications optical set-up reconstruction, since undergo changes. Thus, disclose information about difference relative positions (stationary) configurations from these emanate. chapter, shall investigate cases special interest engineering. First, present elements concerning determination deformation an opaque body with a diffusely reflecting surface. Here, concepts Sect. 2.3 will combined those outlined 3.1.1. Secondly, intend study interferometry phase objects, i.e., spatial variation index refraction transparent medium. This topic relates Sects. 2.2