RESUMO
We present a new method for displaying light in flight. Fresnel holograms are recorded directly on a CCD sensor, electronically stored, and numerically reconstructed. Experimental results are shown. From different parts of a single holographic recording, different views of a wave front can be reconstructed. This means that the temporal evolution of a wave front can be observed by numerical methods.
RESUMO
The principle of recording holograms directly on a CCD target is described. A real image of the object is reconstructed from the digitally sampled hologram by means of numerical methods.
RESUMO
The fundamentals of digital recording and mathematical reconstruction of Fresnel holograms are described. The object is recorded in two different states, and the holograms are stored electronically with a charge-coupled-device detector. In the process of reconstruction the digitally sampled holograms are applied to the different coherent optical methods as hologram interferometry and shearography. If the holograms are superimposed and reconstructed jointly, a holographic interferogram results. If a shearing is introduced in the reconstruction process, a shearogram results. This means that the evaluation technique, e.g., hologram interferometry or shearography, can be influenced by numerical methods.