<title>Concept of optical reconstruction of digitally stored holograms</title>

Abstract

The progress in high resolution CCD detector technology provides the electronic medium for digital registration of holograms. This possibility is widely used in digital holography, which allows reconstruction ofnumerically stored microinterferogram. This approach is very useful for optical metrology application, however it is not convenient to real time visualisation of 3D object reconstruction. In the paper we propose to use only the stage of digital registration and then transfer these data to LCD matrix to form an optoelectronic version ofmicrointerferogram. This hologram is reconstructed optically by a laser beam, giving possibility to visualise an amplitude-phase object's image. These procedures together with fast LCD and proper optical imaging system should enable to produce digital holographic films.

Adaptive holographic illumination in comparative electronic speckle pattern interferometry

“…In ESPI comparative measurement is possible if two objects are present in the two arms of the interferometer at the same time [3,4] or if hologram is made of one of the objects and used for holographic illumination of the other one [5,6]. This illumination can be performed using digital holograms, due to the recent development of Spatial Light Modulators (SLM), which makes the optical reconstruction of digital holograms possible [7]. The SLM is also capable to illuminate the object with computer calculated wave fronts.…”

Extension of the measuring range in deformation measurement using artificial phase compensation

“…Development of Spatial Light Modulators (SLM) opened a new area in coherent optical metrology [6][7][8][9][10] . These modulators are capable to optically reconstruct digital holograms; therefore they can be used as active holographic optical elements in TV holography or in digital holography.…”

Comparative electronic speckle pattern interferometry using adaptive holographic illumination

“…[5][6][7] This illumination can be performed using digital holograms, due to the recent development of spatial light modulators (SLM), which makes the optical reconstruction of digital holograms possible. 8 This approach is a straightforward digital implementation of the analogue comparative measuring technique, where regular hologram plates are used to store and reconstruct optical wavefronts. An SLM is also capable to generate computer calculated wave fronts (not belonging to an existing object), and multiple projections can be performed during the measurement time.…”