The Holo-Diagram. VI: Practical Device in Coherent Optics.

Ordinary interferometry, hologram interferometry, contouring, speckle, moiré, ordinary radar, Doppler radar, optical Doppler velocimeter, Doppler holography, and gated viewing are all discussed, and it is vdemonstrated how closely these methods are related to each other. One single diagram, the holo-diagram, can be used for the evaluation of each method and even for combinations of the methods. The diagram is constructed for the study of interference patterns when an object is placed in the vicinity of two focal points representing either one point of illumination and one point of observation or two points of illumination or two points of observation. It reveals interference surfaces in space and how ordinary interference fringes are formed where an object intersects these surfaces. With a common moiré analogy the three-dimensional sensitivity distribution and the fringe patterns of each of the methods can be simulated. Finally it is pointed out that the diagram demonstrates the interference limits and diffraction limits of any method of optical information retrieval.