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Modern 3D visualization techniques can be applied in many sectors (eg. entertainment industry, communications, medical applications, automotive industry, etc.). The holography was considered as a sufficient method for 3D imaging and many attempts were done to develop an appropriate technology for recording and reconstructing holograms of still and motion objects. However, during the last decade, non-holographic computer based techniques took the lead in the 3D displaying industry. Although 3D visualization using these so called stereoscopic techniques can be some times even more realistic than holography (true color, motion), it brings also specific problems. For example accommodation of observer’s eye is often in disagreement with vergence of eye-pair, which can be significantly disturbing for some observers. Therefore, for some applications, the holographic approach still represents the only sufficient alternative.
In this paper, different techniques of three-dimensional imaging with respect to particular applications are discussed. Various principal approaches to 3D synthesis are analyzed. Main focus is held on realization techniques based on image synthesis in the hologram plane and in observer’s eye pupil plane. A fully automatic device is presented, which was developed at our department. The device is capable of exposing larger format holograms of different types from a set of 2D spatial views. Proper alignment of spatial channels, true-color synthesis, and kinetic effects in images are discussed in detail. The exposed samples are compared to 3D holograms with directly written micro-structure, which are also prepared at the department using an in-house developed writing device. Finally, synthetic techniques of 3D imaging are compared to classical image holograms realized from a real model. Experience have shown, that for some applications the classical approach is still the most suitable. This is demonstrated on an interesting application of hologram for opthalomologic system for dynamic measurement of ocular deviations, which has been researched recently.
