Compensation or comparative measurement is a natural way to overcome the limited measuring range of TV holography
or digital holography. In this case the resultant displacement field is the difference of the actual deformation and a known
deformation pattern. The compensation can be digital, because these measuring techniques operate with images recorded
with digital camera.
Development of Spatial Light Modulators (SLM) enables the application of active holographic optical elements in
coherent optical metrology. These modulators are capable to reconstruct digital holograms optically; therefore they can
be used as active holographic optical elements. The goal of the project was to perform adaptive comparative
measurements, where an optically reconstructed image of a recorded or simulated single or double exposure hologram is
used for holographic illumination of another object.
In this paper conventional TV holographic or digital holographic arrangement with holographic object illumination
applied for comparative displacement measurement with adaptive features. Measurement setups were built, containing
devices performing feedback, which is capable to project the real image of the master object - using its previously
recorded or computer simulated digital holograms - onto the test object to calculate the difference deformation directly.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
János Kornis and Richárd Séfel
Extension of the measuring range in deformation measurement using artificial phase compensation
", Proc. SPIE 8413, Speckle 2012: V International Conference on Speckle Metrology, 84130E (September 11, 2012); doi:10.1117/12.978774; http://dx.doi.org/10.1117/12.978774